• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    The present invention relates to an electrohydrodynamic generator unit with a chamber. The chamber is provided with at least one hole electrode with at least one hole. The hole electrode is connected to a voltage source and is intended to generate a direct voltage field in the chamber. The chamber is further connected to at least one reservoir that contains a fluid such as water. The chamber further comprises at least one collecting electrode coupled to an electrical load. The elec trohydrodynamic generator unit functions in that said reservoir is coupled to an electrically earthed fluid feeding member arranged in the chamber, which member is intended, via at least one opening adapted to corresponding holes in the hole electrode, to eject drops of fluid from the reservoir towards the hole electrode, which fluid drops are charged by an electric direct voltage field generated by the hole electrode, to which a voltage has been applied, and are then accelerated through the chamber past the holes in the hole electrode and strike the collecting electrode, where the drops deposit their charge. The collecting electrode is intend¬ ed in turn to be coupled to an electrical load via the earthed fluid feeding member, wherein a closed circuit is formed, which is capable of driving the load with the charges that have been deposited on the collecting electrode.
    公开号:SE1200377A1
    申请号:SE1200377
    申请日:2012-06-25
    公开日:2013-12-26
    发明作者:Mose Akyuz
    申请人:Totalfoersvarets Forskningsins；
    IPC主号:
    专利说明:

    15 20 25 30 35 2 down into the different cups. The rings are also electrically isolated from the environment and each other. As can be seen from the figure, the left ring is electrically connected to the right cup and the right ring to the left cup. Initially, the entire system is electrically neutral. When the system is now activated, that is, when the water begins to seep down through the holes and the rings to the beakers, there will be a phenomenon connected to electrostatic induction. This is because the water that seeps into the beakers will cause charges of opposite polarity to build up in the two beakers. The reason for initially creating a net polarization between the beakers is currently not completely clear, it could be because the water droplets pick up some charge through the so-called tribo effect when they come in contact with the mouth of the liquid container or with the air during the fall against the beakers. In any case, there will be an instantaneous imbalance in the charge distribution between the beakers. The ingenious thing about the device is now that if the right ring (for example) receives an excess of positive charges, these will be distributed on the ring so that the mouth closest to this ring receives negatively charged liquid droplets. These negatively charged droplets will then pass through the positively charged ring and land in the right beaker. This causes the right cup to be negatively charged. The negatively charged beaker will in turn amplify the effect in the positively charged beaker and this process proceeds as long as the dripping continues. As the voltage difference between the beakers becomes larger and larger, this will eventually cause the water droplets to either bend off, which causes the charging effect to stagnate, or there is an electrical surge which empties the beakers of its net charges.
    Further prior art will be described when a more detailed description of the invention and the physics behind it has been given.
    Figures Embodiments will be described with the aid of the figures, where: Figure 1 schematically shows a possible variant of Lord Kelvin's device.
    Figure 2 shows an EHD according to known technology.
    Figure 3 schematically shows an embodiment of EHD according to the invention, here a chamber with a single electrode set, with an anode, called a hollow electrode, a liquid cathode, called a collector electrode, and a fluid supply structure is shown. The designation z in the figure represents the impedance in the load.
    Figure 4 shows a further embodiment of an EHD according to the invention, here the same hole electrode - collector electrode set as in figure 3 is shown, however the heel electrode here is provided with a plurality of holes fitted with a plurality of nozzles arranged on the fluid supply means.
    Figure 5 shows a further embodiment of a device according to the invention, where instead two hole electrodes with corresponding cathodes are symmetrically arranged around the fluid supply means. The fluid supply means is provided with a plurality of nozzles arranged on the sides opposite the hole electrodes. The nozzles are fitted with corresponding holes on each of the hole electrodes.
    Figure 6 shows in cross section an embodiment of the invention where a closed fluid system is used in the electrohydrodynamic unit. Only the fluid system is shown in the figure.
    Figure 7 shows in cross section how water is led into the fluid supply means from a reservoir.
    When the channel towards the nozzles has only one opening, the pressure differences will force the liquid out through the nozzles arranged on the fluid supply means.
    Figure 8 shows in cross section how a plurality of fluid supply means can be fed with liquid from the same reservoir. It also shows how the fluid flowing from the collector electrode is collected and returned for reuse.
    Figure 9 shows the same principle as in Figure 8. However, the water in this figure is pushed out in different directions by the fluid supply means. by means of nozzles arranged on each side of Detailed description of the invention and preferred embodiments In the following, the invention will be described both functionally and component-wise with the support of the figures. A number of different names of components will be used, which is why we provide a shorter glossary with functional descriptions. 10 15 20 25 30 35 Chamber (1) refers to the entire enclosure of the device. The chamber is provided with, or is connected to, a reservoir (6) with a fluid. The purpose is for the fluid to be taken from this reservoir and led into the chamber via a nozzle. It is important that the fluid divides into particles, or small drops of liquid, as it leaves the nozzle. To achieve this particle separation, mechanical or electrohydrodynamic atomization of the fluid can be used. In the latter, the so-called Taylor angle is searched for (which can be found by varying the high voltage field in the chamber). These techniques are well known in the art and will not be described further here.
    By fluid supply means (4) is meant a device which can be grounded and which ensures that the fluid / liquid, usually water, is taken from the above-mentioned reservoir and pushed out of the reservoir into the chamber via a nozzle (9). In one embodiment this is achieved by an overpressure present in the reservoir, i.e. the pressure in the reservoir is considerably higher than the pressure present in the chamber. The chamber pressure is usually at normal atmospheric pressure. When the nozzle creates an opening towards the chamber, the water will, due to the pressure equalization, be pushed into the chamber. Another possibility is that the water is centrifuged and when a sufficiently high rotational speed has been obtained, cavities are opened in the centrifuge. In this way, water can be pushed into the chamber. Given here is that the openings in the centrifuge are directed towards the chamber. If a centrifuge or similar devices are used to increase the speed of the liquid, it is required that a motor drive the centrifuge. In one embodiment, the fluid supply device may be a nozzle.
    Needle electrode refers to an electrode used to generate a corona discharge.
    This type of electrode is not used in the present invention but is an essential part of the prior art.
    Hole electrode (2) refers to an electrode system through which the liquid droplets are to be fired.
    The hollow electrode must be energized to a considerable voltage by means of a DC voltage source connected to the hollow electrode. The purpose of the arrangement is to charge the liquid droplets that are pushed out of the nozzle via the induction effect.
    The hole electrode is in principle a structure made of an electrically conductive material which is provided with one or more holes of sufficient diameter to allow a charged drop of water to pass through. The collector electrode (3) is an electrode system which in one embodiment is arranged at the outer edge of the chamber, beyond the hole electrode seen from the fluid supply means. Another cathode arrangement is shown in an embodiment schematically shown in Figure 5.
    A collector electrode is a cathode plate intended to receive charged liquid droplets.
    The cathode plate or collector electrode is further intended to be connected to an electrical load with an impedance z. The term collector electrode is used to illustrate that its function is to capture charged fluid droplets which are first ejected from the fluid supply means and then charged and accelerated towards the collector electrode where they are collected. in. In a preferred embodiment, the collector electrode is constituted by a liquid cathode plate, that is, a cathode plate with a potential which depends both on the collected charge on the plate and also on the background field, i.e. the voltage on the hole electrode. In embodiments of this invention described in the following, the collector electrode has the opposite polarity with the hole electrode.
    With reference to figure (3), a possible electrode configuration according to the invention is now described. In the chamber (1) a needle-shaped nozzle (4) is arranged at one end.
    The nozzle has a length, a radius and is further grounded. The nozzle is connected to a liquid container, not shown in the figure, and is arranged to take water from the liquid container and expel water droplets into the chamber at high speed. At a certain distance from the nozzle, a hole electrode (2) is arranged. The hole electrode is provided with a hole arranged directly in line with the nozzle in the nozzle. The purpose of the hole is to let the water droplets protruding from the nozzle through. The hole electrode is energized to a high voltage using a DC voltage source. Next to the hole electrode, towards the end of the chamber, a collecting electrode (3) is arranged. This collector electrode is a so-called electrically liquid electrode. By this is meant that the collector electrode assumes a potential which depends on the charge present on the electrode but also on the surrounding field distribution. the collector electrode, unlike the hole electrode, has no hole. the collector electrode is further connected to an electrical load and to the grounded nozzle. In this way, a closed electrical circuit is created between the nozzle, collector electrode and load.
    When using a device according to Figure 3, the following will take place: A quantity of liquid, the liquid may suitably be water, is taken from the container and led via the nozzle into the chamber. The amount of water will be divided into water droplets which are pushed into the chamber at high speed. If the hole electrode is now given a positive voltage, the water droplets, by electrostatic induction, will receive a negative charge when they leave the nozzle. The resulting force on the droplets when they are pushed out of the nozzle will therefore be very large in the direction of the hole electrode.
    This is because the forces that push out the droplets and the electrical force on the droplets from the hole electrode are in the same direction. In the figure, this has been symbolized by an arrow. As a result, the water droplets are given an even higher speed when they leave the nozzle than would be the case if there was no electrical drop.
    As the droplets travel in the area between the nozzle and the hole electrode, as they approach the hole in the hole electrode, they will bend towards the edge of the hole. However, as they are given a considerable speed when they are pushed out of the nozzle, they will not have time to bend off too much but will pass the hole. Consequently, the distance between the mouth of the nozzle and the hole in the hole electrode must not be too large to avoid the drops being caught by the hole electrode and instead allowed to pass through the hole.
    Another advantage of having a short distance is that the voltage on the hole electrode does not have to be so high to obtain an atomization and charging of the fluid.
    Once the droplets have passed the hole in the hole electrode, they will experience an electric field which is opposite the field on the opposite side of the hole electrode. This causes the water droplets to slow down. In the figure, this has been symbolized by two different arrows.
    By calibrating the ejection speed of the water droplets and the voltage across the hole electrode, it is possible to ensure that all water droplets ejected from the nozzle travel all the way between the hole electrode and the collector electrode to fall into the latter.
    When the droplets strike the collector electrode, they will automatically deposit their charge on the collector electrode and then drain off it. This causes the collector electrode charge to build up the more drops that fall on it. The charge that builds up on the collector electrode can then be recovered by connecting the collector electrode to a load via a connection to the grounded nozzle. This creates a closed circuit where electrical energy can be extracted from the mechanical energy from the movement of the water droplets. The main fact that must be taken into account when intending to convert the kinetic energy of a liquid into electrical energy according to the present invention is that the liquid must be charged and atomized. The invention does not work with a continuous and neutral liquid. So the main problem is to get a charge of a moving liquid. In what follows, we will give some examples of how you can physically charge a fluid in motion.
    One possible way is to allow the liquid to flow through a perforated and energized hole electrode which is given a sufficiently high electric field in each cavity to thereby create a so-called corona discharge. The corona discharge will deposit a portion of the emitted charge on the liquid flowing through the holes in the electrode. This is an alternative way to recharge a liquid. To obtain an efficient charge of the liquid, an efficient corona discharge is required. According to Lord Kelvin's device, the liquid is charged instead by polarizing liquid droplets through the induction effect. If a free-flowing liquid were to be used, this device would not work as the induction effect will not charge the liquid. Lord Kelvin's device is therefore based entirely on the induction effect.
    There are also opportunities to extract energy from a continuously flowing liquid in an electric background field. However, an extremely high flow rate of the liquid is required so that the convection current of the liquid is greater than the conduction current. Otherwise, a net current is obtained through the liquid discharging from the electrode system.
    As the device according to the invention uses drops of water (or of any other suitable fluid), the problems of the high velocities required for a liquid flow are overcome. In comparison with Lord Kelvin's device, a device according to the invention also provides an opportunity to select the degree of polarization of the water droplets and thus the amount of charge. This is done by varying the external field that is laid over the hole electrode. The higher the voltage applied across the hole electrode, the higher the degree of charge of the droplets. Thus, one can pick out higher power in the end.
    Before more embodiments are given, an EHD generator according to the prior art will be briefly described here. We refer to figure 2 which shows a sketch for a principled EHD setup. The array consists of a needle-shaped electrode, a grounded attractive ring electrode at the narrowest region of the nozzle, and a collector electrode. All these parts are placed along an insulating pipe system (here a partial selection nozzle). High voltage is applied between the needle-shaped electrode and the attractive ring electrode to thereby create a corona discharge from the needle electrode which releases free electrons.
    These electrons are assumed to bind to the liquefied gas and drift in the direction of the collector electrode. The shape of the pipe system is arranged to provide a cooling to the flowing gas as it passes the narrow hole in the nozzle and is thus condensed into liquid particles (aerosols). These liquid particles will then be charged by colliding with the charged gas particles and then they will drift in the background flow of gas. When the gas and the charged liquid particles have passed the narrow hole, the charged particles are allowed to move towards a braking electric field until they reach the collecting electrode where they deposit the charge. The efficiency of an EHD as above has been estimated at a maximum of 10.8%. In reality, however, this measure is never reached, but the efficiency is usually in the order of 2% (for a power of 400 W and an overpressure of 30 bar). The main causes of losses are the electrical strength of the electrode system and that the charge transfer between the corona electrode and the liquid particles is far from optimal. The latter is due to the fact that the free electrons created during the corona discharge do not cover such a large volume but are rather located around the corona electrode. Another limiting factor is that energy is required to convert the propellant gas (specifically, water vapor) into liquid particles. This energy loss reduces the available kinetic energy of the system. A further reduction of the kinetic energy in the system follows from the fact that it is the collisions of the gas particles with the aerosols that create the driving force of the same. This power transmission reduces the available kinetic energy of the system.
    According to the present invention, several of the problems associated with conventional EHD technology are overcome. According to the invention, liquid droplets are pushed out of a nozzle via an externally arranged compressive force. As liquid is pushed away and gas is not used, a higher density of the flowing medium will automatically be obtained. This leads to a higher energy density and that the energy losses that arise due to phase transformations disappear. Since the flow of liquid particles in the chamber according to the present invention is also controlled by the external pressure, the system will also not give any major energy losses due to collisions between the propellant gas and the aerosols. 10 15 20 25 30 35 9 According to the invention, the liquid droplets are charged via electrical induction. This causes each drop of water to be charged and can travel through the system to deposit its charge on the collector electrode. This differs from conventional EHD technology with corona discharge where the main charging takes place with the aerosols that are in the immediate vicinity of the corona discharge. Furthermore, according to the present invention, the degree of charging can also be controlled by varying the voltage applied between the nozzle or nozzle and the hole electrode.
    The charge transfer according to the invention is also not time-dependent, which is the case with corona discharge-dependent devices. This results in a substantially instantaneous charge transfer which provides a continuous charge deposition at the collector electrode.
    According to both the conventional EHD technique and the technique of the present invention, there is an acceleration of the charged droplets in the space between hole and plate. Furthermore, on the other side of the hole there is also a plate electrode that creates a field where the drops can be braked up. In order not to give the collecting electrode too high a charge and thereby create such a large field that the droplets are bent off, the velocity distribution of the incoming water particles must be within a narrow range. The present invention provides a device with precisely these possibilities. EHD according to the prior art instead gives quite fluctuating speeds which is due to the fact that the area for phase transformations is quite elongated in a partial selection nozzle. Thus, it becomes difficult for a device according to the prior art to select a potential that does not bend by the particles before they hit the collector electrode.
    Another design of an EHD generator is found in U.S. Patent No. 4,677,326, to inventor Alvin Marks. This device is based on extracting energy from the movement of aerosols by utilizing a wind force that drives the aerosols in a background field. The aerosols are charged by allowing them to pass through needle-shaped nozzles and a live perforated anode. The wind flow passes through the perforations in the same electrode system from which the aerosols are ejected. A construction according to U.S. Patent No. 4,677,326 becomes rather large due to the large distances required between the hole electrode and the collector electrode in order to be able to efficiently utilize the wind power to move the charged aerosols past the hole electrode and towards the collector electrode. Accordingly, the present invention enables an improved device which, by utilizing the ejection of the water droplets, can be made considerably smaller.
    Because the device can be made so small compared to the prior art, a possibility is also provided to construct an electrohydrodynamic unit which consists of a large number of devices according to claim 1. This gives the possibility to multiply the power output as several collecting electrodes will be hit by large number of water droplets. Some variants of such constructions will be described below.
    Before embodiments are given, an estimate of various properties of an EHD generator according to the present invention will now be given. The purpose is to provide an estimate of the performance and dimensions required for the device to operate. To maximize the values of the dimensions, experiments are necessary. Given what is reproduced in this application, such experiments are routine and self-evident to a person skilled in the art.
    First, an estimate is given of the available kinetic energy and effect of the water droplets. An important quantity here is the speed of the water droplets in the mouth of the fluid supply means. The higher the initial velocity of the droplets, the more kinetic energy is available in the EHD system. Another important quantity is the electrically generated energy when braking the charged droplets. This quantity depends on how efficiently the drops can be charged and how effective the braking is. Large droplets will be charged more than small droplets and consequently these larger droplets will require extremely high electric fields to be slowed down. Very fast drops will also require high electric fields to be slowed down.
    In general, excessive electric fields are not desirable due to the risk of electric shock. Therefore, a balancing of the quantities is what is required for maximum performance. Probably the most important parameter in the system, the efficiency, is given by the ratio between kinetic energy and the generated electrical energy.
    An estimate of how much kinetic energy is available in an EHD generator with only one nozzle, see Figure 3, can be obtained as follows.
    In general, for the kinetic energy, where a is the velocity and m is the mass of the flowing liquid. If now the expression above is derived with respect to time, k = d_EL = ld_m.v2 É.i (v2) = l.d_m.v2 (2) dl 2 dl 2 d! 2 d! an expression of the change of the kinetic energy, i.e. a mechanical effect, for a constant flow rate. Furthermore, dm _ dV a '_ Pa where dm / dt is the mass flow rate (3) density and dV / dt is p is the volume flow rate (i.e., the amount of liquid passing an imaginary area per unit time). If this expression (3) is used in expression (2), a relationship is obtained for the mechanical effect available in an EHD as follows fl = %% = šp% § »2 ro The formulas above make it possible to estimate available kinetic energy and effect from a container which ejects liquid from a tube having a radius r and the length l. We assume here that the velocity of the liquid is the same as the velocity of the droplets ejected from the tube. Furthermore, these droplets are assumed to have a density p, to be spherical and to have a size (i.e., a diameter) which substantially corresponds to the diameter of the tube.
    We obtain for such a drop the following mass 47: m = p'V = p ' V3 The flow rate vi equation (1) is given in the stationary case of Poiseuille's equation: ëK_ fl1fl: (Q d; sn 1 ”where n refers to the viscosity of the liquid The volume flow rate dV / dt is in turn given by dV _- = A 7 d: v () Normally there will be no stationary flow in the tube so experiments may be necessary to maximize efficiency. Instead the flow rate will vary along the length of the tube and depend on the exact geometry of the tube attachment in the container and the mouth of the tube, disregarding such complications, using Poiseuille's equation above, one can obtain an approximation of the velocity of droplets at the mouth of the tube. We assume in the following numerical example that we have a water tank with a pressure of 5 bar (5x105 Pa), running from this tank is a pipe which opens into the chamber through which pipe liquid flows. mmaren, ie on the outside of the pipe, is normally atmospheric pressure 1 bar. This gives a liquid pressure difference of 4 bar. Assume further that the tube has a radius of 5 micrometers and a length of 25 micrometers and that the liquid used is water. With the viscosity of water 1.04x10'3 Ns / mz, one can obtain from expressions (6) and (7) 2 A vJ - paso m / s (s) 817 l i.e. v = 50 m / s. Since the flow velocity depends squarely on the radius of the pipe, we see that the velocity becomes higher if the diameter of the pipe is larger. However, the water droplets also become larger, which is not always desirable as, as mentioned earlier, significant electric fields are required to slow down large water droplets. Furthermore, the velocity of the liquid at the mouth is proportional to the inverse of the length of the pipe. This means that a shorter pipe provides higher speed. This is advantageous as a shorter tube enables a more compact EHD device well suited for miniaturization. So in order to obtain suitable dimensions for an EHD device to be miniaturized, one should compensate the short pipe length with a smaller radius of the pipe.
    Finally, we can numerically determine the kinetic energy of a drop with a radius of 5 micrometers, a tube with a radius of 5 micrometers and a length of 25 micrometers to Ek = 65-10 ”J. For the same construction, mechanical affect tongs = 49-10 * W.
    With these estimates made, estimates will now be made to provide a measure of how much of the kinetic energy can be converted to electrical energy in a device according to the present invention. An important parameter in this estimate is the degree of charge that the liquid droplets carry with them when they leave the mouth of the fluid supply means. The amount of charge will depend on the strength of the electric field, the electrode configuration in the chamber and the exact geometry of the droplets as they leave the mouth. In principle, it is impossible to theoretically calculate the case calculation methods and, above all, repeated attempts are necessary to determine the induced charge for the general reason why numerically optimal charge is included. However, it should be a straightforward task for a person skilled in the art to find more or less optimal efficiencies through experiments by varying the field strength, the tube geometry and the electrode configurations. However, a very simplified calculation can be made which shows what speed a known charge gets when it is accelerated in a background field between a grounded nozzle and a hole electrode with a given positive potential GD. The mouth velocity of the droplet is assumed to be given by equation (8) and it is assumed to start at the mouth of the fluid supply means. Furthermore, the drop is assumed to end its journey in the hole on the hole electrode. We assume as the first approximation that it moves straight ahead towards the hole in the hole electrode, i.e. it has no acceleration in any other direction than straight ahead, consequently there is a one-dimensional movement along the axis of the EHD device.
    By using the energy conservation for the charged droplet, the following velocity equation is obtained: '"'" ° 2 = ”“ '' 2-Q- fl> <9) 2 2 where v1 is the velocity of the droplet when it reaches the center of the hole electrode. Based on this, one can estimate the potential CD] required to brake a drop with charge Q. Assuming that the starting point of the drop is the center of the hole electrode and the end point is the collecting electrode and the initial velocity V1, the following equation is obtained: 2 m-vl = -Q ~ ( ) (10) By solving equation 10, it is obtained that the potential of the collector electrode is negative, i.e. it slows down the charged drop. As can be seen from equations (9) and (10), the only unknown variable is the induced charge.
    The potential (D on the hole electrode is a quantity that should be set in such a way that for a given distance between the nozzle and the hole electrode no electrical flashover is obtained.
    This is a complex theoretical problem that must be iterated for each imagined electrode configuration. Therefore, for each assumed electrode configuration, one must apply a potential to the hole electrode and then check that one does not get an overshoot in the system with the drop located just at the mouth of the electrode tube.
    With such an iteratively found potential, one can then calculate the induced charge Q of the imaginary drop. With the obtained value of the induced droplet charge inserted in equation (9), one can then estimate the velocity of the droplet in the gap between the nozzle and the hole electrode. Finally, by using equation (10), one can calculate the potential CDI that causes the drop to just slow down when it reaches the collector electrode. If this calculated potential is applied to the collector electrode, an optimal decelerating electric field is obtained. Another embodiment of an electrohydrodynamic generator, in addition to that described above in connection with Figure 3, will now be described with reference to Figure 4. In the figure, the electrohydrodynamic generator comprises a hollow electrode (2) provided with a number of holes (5). Furthermore, a plate is provided provided with a number of fluid supply means (4), here in the form of nozzles, each of these nozzles being provided with a nozzle or orifice fitted in line with a corresponding hole in the hole electrode. As in the previously described embodiment, the intention is to place a high voltage field over the hole electrode to charge the water droplets ejected from the various fluid supply means and allow these droplets to accelerate through corresponding holes in the hole electrode to fall onto the collector electrode and deposit their charge there. Here, too, the collector electrode is connected to an electrical load via a connection to the electrically grounded fluid supply means. The physical that takes place in this embodiment is the same as described in connection with figure 3, the only difference is that more water drops can be fired per unit of time. So in the same way as before, a closed circuit is created that can drive the load. In this embodiment, where a plurality of fluid supply means are used, it can be arranged to collect its liquid from a common fluid reservoir, but it is also possible for each of the nozzles to collect the liquid from its own reservoir. The former is preferable if one intends to create a closed fluid supply system. That is, when the liquid flows from the collector electrode, it is collected and returned via a water line to the various nozzles. More about such a closed system will be described later. Yet another embodiment of an electrohydrodynamic generator is shown in Figure 5. In this figure, a plate with fluid supply means as in the embodiment shown above is arranged centrally in the middle of the chamber. Unlike the previous embodiment, the plate in this case is provided with nozzles or orifices and nozzles on both sides of the plate. This makes it possible for the fluid supply means to push water droplets in two directions in the chamber. Accordingly, the chamber is also provided with two hollow electrodes (2, 2 ") provided with holes (5, 5 ') linearly fitted with an orifice on a corresponding nozzle on the fluid supply means.
    Beyond each of these perforated electrodes, towards the ends of the chamber, two collecting electrodes (3, 3 ') are arranged. These collector electrodes are connected to a load via the grounded fluid supply means. Both the collector electrodes and the hollow electrodes will be arranged substantially symmetrically around the plate with fluid supply means. The physical that takes place in this embodiment is the same as described in connection with Figure 3, the only difference is that more water droplets can be ejected per unit time. In use, this will create a closed circuit that can drive the load. It should be noted that the electrical loads may be different, which makes it possible for one part, for example the left part of the chamber, to drive a specific load while the right part drives another load. In this case, two different closed circuits are created. An embodiment as above is ideal for miniaturizing the device. One of the significant advantages of an electrohydrodynamic generator according to the present invention is that it can be miniaturized so easily. This allows a large number of droplets to deposit their charge in a very short time. This in turn means that a large energy consumption can be made per unit of time compared to the known technology.
    An extension of the latest embodiment provides an electrohydrodynamic generator unit provided with a number of fluid supply plates with associated and symmetrically arranged hollow electrodes and collecting electrodes. The idea is that the chamber will be provided with a large number of such subsystems in order to thereby optimize the performance when the generator is miniaturized. The output power per unit time grows with the number of subsystems.
    To understand the above embodiment, reference is made to Figure 5 and Figure 7, respectively. Figure 7 shows a variant of a fluid supply means suitable for use with symmetrically arranged hollow electrodes (2,2 ') and collector electrodes (3,3'), see arrangement in Figure 5. The fluid supply means (4) in the figure consists of a hollow sheet or a hollow plate or a tube-like structure. The fluid supply means is anchored in the walls of the chamber and has a closed end (4a) and an open end (4b).
    The open end is connected to the fluid reservoir (6) via a channel (21). Furthermore, the walls of the sheet, plate or tube-like structure are provided with nozzles (9a) and (9b), respectively, arranged on each side of the sheet or tube-like structure and opening into chambers (1). Although the figure shows nozzles as pipe-like nozzles protruding from the wall, it is also possible to use only cavities in the wall. Nozzles may be preferred over cavities as this results in lower voltages being required across the holding electrodes to charge the water droplets. In use, water or other suitable fluid is now passed from the pressurized reservoir (6) to the hollow sheet, plate or tubular structure ( 4) via channel (21). With the end (4b) connected to the channel open, the pressurized fluid enters the cavity at high speed. When the opposite end (4a) is closed, the fluid will be forced out via the nozzles (9,9 ') due to the pressure in the chamber (1) being kept considerably lower than the pressure in the reservoir (6). In this way a fluid supply means is created which can spray fluid in two separate directions in the chamber. If two hole electrodes (2) and (2 ') are now arranged on each side of the fluid supply means (4), the nozzles 9 and 9', respectively, can project fluid droplets towards each hole electrode.
    Furthermore, if two collecting electrodes are arranged outside the corresponding holding electrodes, seen from the fluid supply means, these will be fed with drops charged by the respective holding electrode. Which in turn deposits their charge on their intended collector electrode. Thus, one and the same fluid supply means feeds two separate hold-collecting electrode arrangements, which doubles the power output per unit time. In order for this embodiment to work, it is required that there is a pressure difference between the fluid reservoir or channel 21 which leads liquid to the fluid supply means and chamber (1). One way to ensure this is that the reservoir or duct has an overpressure because the chamber (1) is at atmospheric pressure. By allowing the chamber to have an opening towards the surroundings, it can be ensured that the chamber is always at atmospheric pressure. The overpressure in the reservoir or channel can be ensured by means of an externally connected pump. Alternatively, external pumps can of course be connected to both the reservoir / channel and the chamber.
    When it comes to the design of the electrohydrodynamic generator, it is to attach hale electrodes, the walls of the chamber so that they run along the entire height of the chamber. This requires a possible fluid supply means and collector electrodes in fixed mounting of the constituent components and in the case of miniaturization, where we are talking about units in the order of millimeters and smaller, this becomes complicated.
    The alternative is to miniature the components from a piece of material instead of miniaturizing the components. Thus, all parts will sit together, hollow electrodes and collector electrodes thus form sheets of material that have not been etched away.
    The fluid supply means will consist of a hollow and sheet-like structure which is provided with cavities or etched nozzles in the walls. Through these cavities or nozzles, the pressurized fluid will be forced out during use. This method of manufacture is very practical when using hole electrodes with many holes and fluid supply means with many nozzles.
    Furthermore, the manufacturing method is also well suited when manufacturing a number of units in a row. You then simply etch out as many units as needed in the same piece of material. When the material is intended to conduct electricity, the material should either be conductive itself, or alternatively be coated with a conductive material on the sections where voltage is to be applied and currents flow. For example, copper plating of relevant sections is sufficient to achieve this purpose.
    Referring to Figure 6, an electrohydrodynamic device with a closed fluid system is described below. The advantage of a closed fluid system is that the reservoir can be incorporated in the device and that therefore no frequent filling of liquid in the reservoir is required. By the liquid which has been charged up and deposited its charge being led back to the fluid supply means, the same liquid can be used again and again. In figure 6 we see a reservoir (6) partially filled with a fluid / pressurized air. Because only parts of the reservoir are filled with liquid, the rest can be filled with pressurized air. The reservoir is further provided with a valve at its lower edge. This is a control valve that can be arranged to regulate the time and amount of water to be discharged from the air-liquid tank. Connected to the valve runs a channel (21) through which the liquid is fed from the air-liquid tank to the nozzle or nozzles in the fluid supply means. These nozzles are not shown in the figure but are represented by the chamber (1) in which they are arranged.
    The figure also shows the chamber (1) of the EHD generator in cross section. The air pressure in the generator chamber is considerably lower than the air pressure in the air-liquid chamber. Advantageously, the pressure is around normal atmospheric pressure. To obtain atmospheric pressure, the chamber may be provided with an opening to the surroundings. Alternatively, the chamber (1) and reservoir (6) or duct (21) are connected to external pumps which ensure that there is a pressure difference. How this is achieved is not essential for the function, as the generator chamber is large enough for the liquid to reach the required relevance is that the pressure difference between the air-liquid reservoir and the velocity. When the liquid which is pushed into the chamber and deposited on the collecting electrode flows from it, the liquid is collected in the lower part of the generator chamber. From the lower part of the chamber therefore runs another channel, a return channel (22) where the liquid is intended to drain out. This return channel (22) is then connected to the channel (21). As a result, due to the large pressure difference between duct (21) and duct (22), the liquid will be returned to duct (21) and thus be able to be pushed back into the generator chamber. Initially, when the liquid is released from the air-liquid reservoir, it may be necessary for duct (22) to contain directly to Alternatively, one may supply the liquid from (22). return duct (22) with a valve that only allows liquid flow in one direction. The liquid to ensure that the reservoir enters the generator chamber and does not enter the channel, that is, in the direction from the return channel (22) to the channel (21). Thus, the system 10 has been provided with an almost closed fluid supply system where the same amount of liquid can all the embodiments described above. It is especially suitable for use because it is charged repeatedly. This system can be used for the miniaturized system where the components are etched from a piece of material. By using this system, the only effort that needs to be made during the process is a pressurization of the air-liquid reservoir. Of course, it is also possible to provide such a closed system with a pump, whereby the liquid flowing out of the generator chamber is pumped back to the duct (21). Normally it would be to ensure that channel (21) the return channel (22). continuously gives an overpressure relative to both the generator chamber and An alternative to the above-described closed fluid supply system consists of a reservoir which contains only pressurized air. That is, no fluid is contained in the container at all. The purpose is that the pressurized air or gas should only be used to pressurize the duct between the generator and the reservoir. Initially, when starting the device, the duct (22) must be provided with liquid. When the valve between duct (21) and the reservoir is opened, high pressure air will leave the reservoir.
    This air movement will entrain amounts of liquid from the channel which can then be pushed in through the fluid supply means. When the charged liquid droplets then drain from the collector electrode, they will drain into channel (22) and then be pushed away again the next time the valve in the reservoir is opened. In this way, by controlling the reservoir valve to be opened periodically over time, it can be ensured that the same amount of liquid can be used many times. In this embodiment, as in the previous ones, it may be preferable if all valves are non-return valves that only allow movement in one direction.
    With reference to Figures 8 and 9, a more detailed description will now be given of two different embodiments which are etched from a piece of material and which are fed with a common fluid supply system which utilizes reuse of the liquid.
    Figure 8 shows an embodiment with a set of EHD units according to claim 2, arranged side by side. It is reasonable that all the included fluid supply means, holding electrodes and collecting electrodes are etched from a piece of material. Said piece of material has a stripe which has been given the designation (1), which corresponds to the chamber in previously described embodiments. According to the figure, three units are further shown where each of these units consists of a fluid supply means (4), a hollow electrode (2) and a collecting electrode (3). The chamber is connected at its upper end to a channel (21) which supplies water or fluid to the unit from the reservoir (6). As shown in the figure, the upper end of the chamber in the figure consists of three openings corresponding to end 4b in figure 7. That is, they are the inlet for water or fluid in the fluid supply means.
    The fluid supply means in this figure is provided with two nozzles (9) which are directed towards two opposite holes arranged the holding electrode (2). Beyond the hole electrode, seen from the position of the fluid supply means, the collecting electrode (3) is arranged. In use, fluid is now taken from the pressurized reservoir (6) and led via channel (21) into each of the open ends (4b) of the fluid supply means (4). As the lower end (4a) of the fluid supply means is closed, as shown in Figure 7, the supplied water will take its way through the nozzles (9), be atomized via the field in the chamber and be ejected into the open space in the chamber between the fluid supply means (4) and holding electrode (2). The droplets then make their way through the hole in the hollow electrode to finally deposit their charge on the collector electrode (3). After the water droplets have deposited their charge on the collector electrodes (3), the water will drain from the collector electrode due to gravity. As shown in Figure 8, the lower section (11) of the area between the holding electrode and the collector electrode is open. This is so that the water will run down from the electrode and be collected in a channel (21) arranged on the underside of the chamber. This channel corresponds to the return channel (22) described in connection with Figure 6. Consequently, the water is then led back to channel (21) to be used again to supply the fluid supply means (4) with water. When this figure shows three fluid supply means and three collecting electrodes, the upper edge of the chamber (1) is provided with three cavities corresponding to the openings of the fluid supply means, while the lower edge of the figure is provided with three openings corresponding to the distance between the holding electrodes and the collecting electrodes. This is an opportunity to arrange a plurality of units according to the invention in line to create an EHD generator with high efficiency per unit time.
    Another embodiment is given by Figure 9. This embodiment is essentially reminiscent of the one given above in connection with Figure 8. The difference is that the fluid supply means here is provided with nozzles which can push liquid droplets in separate directions in the chamber. The fluid supply means is described above in connection with Figure 7. In order to give an estimate of the orders of magnitude which give good results, a table with a set of effective values of the constituent quantities is given below. However, these are not the only possible values but only provide an estimate of the values in an effective dimensioning. To optimize the effect of the device, the exact experiment is required where one can start from the approximations given above and then fine-calibrate the setup. This is a traditional experimental activity in the field of technology and is straightforward for a person skilled in the art. However, below we give an example of a parameter family that can be used. These parameters are exemplary only. As the parameters have an interdependence that is extremely complex, it may be necessary to carry out experiments if one intends to change the parameters and optimize the operation. The values of parameters given in the table are an example that leads to drip rates that lead to an acceptable power output from the device.
    Table 1 Pipe diameter Pipe length Units / sheet Number of sheets (1 sheet = 1 square meter / cubic meter 10pm 25pm 400 million 56 Voltage Voltage Resistance load Electric hole electrode cathode power 100 V 53 kV 26Q 110 MW The table above refers to a fluid pressure of 5 bar over given pipe dimensions, which gives a velocity of the droplets around 50 meters per second.Furthermore, the pipe diameter refers to the diameter of the pipe or the nozzle in the fluid supply means.The pipe length refers to the length of the pipe or channel leading to the nozzle in the fluid supply means.
    Units / sheets refers to the number of units of the electrohydrodynamic generator used in each sheet according to the embodiment given above. In the same way, the number of sheets / square meters defines how many sheets are to be used in the three-dimensional construction. Voltage hole electrode and voltage collector electrode refer to the voltages applied across hole electrodes and collector electrodes. Resistance load refers to the resistance of the load driven by the electrical energy generated in the electrohydrodynamic generator. Finally, electrical power indicates the power that can be picked from the generator with these specific parameters. As mentioned, the complex dependence between the parameters requires that experiments be performed to optimize the output of electrical power. Applications and Use of an EHD Generator According to the Invention An electrohydrodynamic generator according to the present invention can be used in a variety of fields. In principle, it can be a complement to all types of current and voltage sources used to drive an electric load. For example, a device according to the invention can be used to generate high voltage. The rather low voltage used to energize the hole electrodes is converted to an output high voltage by utilizing the conversion of the kinetic energy of the fluid into electrical energy. Of course, this also applies to currents.
    One predictable application is the use of the invention as a complement or replacement for today's turbine-powered technology.
    权利要求:
    Claims (1)
    [1]
    An electrohydrodynamic generator unit comprising a chamber (1), said chamber provided with at least one hole electrode (2, 2 ') having at least one hole (5, 5'), said hole electrode (2, 2 ') being connected to a voltage source (10 ) and is intended to generate a direct voltage field in the chamber, said chamber is further connected to at least one reservoir (6) containing a liquid such as water, the chamber further comprises at least one (15), electrohydrodynamic generator unit characterized in that said collecting electrode (3, 3 ' ) connected to an electric load the reservoir (6) is connected to an electrically earthed fluid supply means (4) arranged in the chamber provided with at least one nozzle (9, 9 '), fitted with the corresponding hole (5, 5') in the hole electrode (2). , 2 '), wherein liquid can be led from reservoir (6) to fluid supply means (4) for firing droplets of the liquid from the reservoir (6) via nozzle (9, 9') towards said at least one hollow electrode (2, 2 '), said liquid droplets intended for charging s up by an electric DC field generated by said at least one energized hole electrode (2, 2 ') and accelerated through the chamber past the holes (5, 5') in said at least one hole electrode (2, 2 ') and incident on the collector electrode (3, 2'). 3 ') for depositing charge there, said collector electrode (3, 3') intended to be connected to an electric load (15) via said fluid supply means (4), a closed circuit capable of driving the load with the charges deposited on the collector electrode is formed. Electrohydrodynamic generator unit according to claim 1, characterized in that it comprises, electrically grounded and fluid supply means (4) connected to a reservoir (6) with a nozzle (9), a perforated hole electrode (2) provided with a hole by a voltage source (10) (5) fitted with the nozzle on the fluid supply means (4), a collecting electrode (3) arranged beyond the hole electrode (2) and connected to an electric load (15) via the grounded fluid supply means, whereby liquid taken from the reservoir is ejected from the nozzle, charged by the the electric field generated by the voltage across the hole electrode (2) is accelerated through the hole (5) on the hole electrode to fall onto the collector electrode (3) to deposit its charge thereby creating a closed circuit over the electric load. (15) and the grounded fluid supply means (4). Electrohydrodynamic generator unit according to claim 1, characterized in that it comprises an electrically grounded fluid supply means (4) connected to a reservoir (6) with two nozzles (9, 9 ') directed in each direction, two perforated electrodes from a voltage source (10). (2, 2 ') provided with each hole (5, 5') fitted with each nozzle (9,9 ') on the fluid supply means (4), two collecting electrodes (3,3 ") arranged beyond the corresponding hole electrode (2, 2') and each connected to an electric load (10, 10 ') via the grounded fluid supply means, liquid taken from the reservoir being ejected from the orifices (9, 9'), being charged by the electric field generated by the voltage across hole electrodes (2, 2 '), and is accelerated through the holes (5, 5') on the corresponding hole electrodes (2, 2 ') to fall on the corresponding collecting electrode (3, 3') to deposit there their charge thereby creating closed circuits over the electric load (15) and the grounded fluid supply means (4). . Electrohydrodynamic generator unit according to claim 2, characterized in that said nozzle (9) consists of a set of nozzles (9), and that said hole (5) consists of a set of holes (5), each of said holes fitted with the corresponding nozzle (9). 9) in the set of nozzles. . Electrohydrodynamic generator unit according to claim 3, characterized in that said nozzles (9, 9 ') consist of a set of nozzles (9, 9'), and that said hole (5, 5 ') consists of a set of holes (5 5'), each of said holes (5, 5 ') fitted with the corresponding nozzle (9, 9') in the set of nozzles. . Electrohydrodynamic generator unit according to any one of claims 1 to 5, characterized in that the fluid supply means is provided with a closed end (4a) and an open end (4b) for taking in liquid from a pressurized reservoir (6), furthermore the fluid supply means is fixedly arranged in the chamber ( 1) and provided with first and second nozzles (9, 9 '), directed in different directions, whereby the liquid is used in use via the open end in the fluid supply means (4) and forced out via the pressure difference between the chamber and the reservoir through the nozzles (9, 9 '). Electrohydrodynamic generator unit according to claim 5 or 6, characterized in that both hollow electrodes (2,2 ') and the collecting electrodes (3,3') are arranged to run through the entire chamber (1) on each side of the fluid supply means (4), the nozzles (9 , 9 ') arranged on the fluid supply means (4) are fitted with the cavities in the corresponding hole electrode (2,2'). Electrohydrodynamic generator unit according to claims 1-7, characterized in that the hollow electrodes (2,2 '), the collecting electrodes (3,3') and the hollow tube structure constituting the fluid supply device (4) are etched from a homogeneous piece of material. Electrohydrodynamic generator, characterized in that it consists of a number of generator units according to any one of claims 1-7, arranged side by side.
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    同族专利:
    公开号 | 公开日
    SE536557C2|2014-02-18|
    EP2865088A4|2016-05-18|
    WO2014003625A1|2014-01-03|
    EP2865088A1|2015-04-29|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    US3122660A|1962-01-12|1964-02-25|Giannini Scient Corp|High-voltage electrostatic generator|
    US3191077A|1962-04-27|1965-06-22|Marks Polarized Corp|Power conversion device|
    US3405291A|1965-10-20|1968-10-08|Curtiss Wright Corp|Rankine cycle electrogas-dynamic generator|
    US3518461A|1967-06-23|1970-06-30|Alvin M Marks|Charged aerosol power conversion device and method|
    法律状态:
    2018-01-30| NUG| Patent has lapsed|
    优先权:
    申请号 | 申请日 | 专利标题
    SE1200377A|SE536557C2|2012-06-25|2012-06-25|Electrohydrodynamic generator|SE1200377A| SE536557C2|2012-06-25|2012-06-25|Electrohydrodynamic generator|
    PCT/SE2013/000099| WO2014003625A1|2012-06-25|2013-06-12|Electrohydrodynamic generator|
    EP13808672.3A| EP2865088A4|2012-06-25|2013-06-12|Electrohydrodynamic generator|
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