Reduction of system energy requirements by manipulating fluids to overcome capillary forces of gas bubble formation on reaction surfaces

Abstract

A fluid associated with a desired chemical or electrochemical reaction is continuously flowed or periodically pulsed across the reaction surface at a flow rate or frequency consistent with the average time required for a desired rate of gas bubbles to grow to a specific diameter as part of the reaction. The fluid flow rate used is sufficient to break the capillary forces of bubbles on the reaction surface at said specific diameter. If pulsating, during periods between periodic fluid flows or pulsations, the fluid either does not flow or flows at a sufficiently low rate to allow for sufficient reaction rates. Additionally, curvature of the reaction surface and flow channels can reduce the surface tension of the bubbles, reducing the flow force required to break off bubbles at an optimal size and therefore reducing the energy required to pump the fluid.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to and benefit of U.S. Provisional Patent Application No. 63 / 392,059, filed July 25, 2022, and U.S. Provisional Patent Application No. 63 / 397,942, filed August 15, 2022, the contents and disclosures of each of which are incorporated herein by reference in their entirety. [Background technology]

[0002] The present invention relates to a chemical or electrochemical reaction that forms a gas that is generated in the contact area of a fluid solution, such as an electrolyte, and a reactive surface, such as an electrode material or a catalytic material, when the same chemical or electrochemical reaction does not occur in the contact area of the same reactive surface with a gas, such as the gas produced during the aforementioned reaction. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] U.S. Provisional Patent Application No. 63 / 392059 [Patent Document 2] U.S. Provisional Patent Application No. 63 / 397942 Summary of the Invention [Problem to be solved by the invention]

[0004] Climate change is one of the greatest threats facing the real world today. Extreme weather events, especially floods, hurricanes, fires, and heat waves, will become increasingly common as the atmosphere continues to be polluted by greenhouse gases produced from the burning of fossil fuels. Therefore, the Earth needs to provide alternatives to polluting energy sources, and countries with high emissions need to shift to policies that avoid the use of polluting fossil fuels.

[0005] Achieving net-zero radiation by the mid-to-late 21st century will be paramount for both developing and developed countries. An essential part of these ambitious goals is carbon-free fuel and energy sources. Renewable energy sources such as solar and wind can provide green electricity, but the electricity generated cannot necessarily be stored and available when consumers need it. And these energy sources cannot alone quickly, efficiently, and cost-effectively replace fossil fuels.

[0006] Hydrogen is a fuel with the ability to store energy for later use. Hydrogen offers many advantages, including not producing any pollutants (its by-product is water), the ability to be compressed into an energy-dense fuel, and the potential to democratize energy use around the world. Furthermore, hydrogen can store energy as an alternative to large-scale batteries or other methods of storing electricity. The development of a robust hydrogen economy would liberate countries currently dependent on fossil fuels and, when integrated with renewable energy sources, significantly reduce the carbon dioxide emissions of any country that uses the fuel.

[0007] During chemical or electrochemical reactions involving the formation of gas bubbles on a surface, the reaction that forms the gas typically occurs at the contact area of the reacting fluid solution with the target surface, such as an electrode in an electrolyte. As the bubbles grow on the reacting surface, they eventually become detached, with sizes stochastically distributed, when capillary forces on the bubbles exceed buoyancy and / or other forces. However, when gas bubbles form on the target surface, reaction is not subsequently possible in the contact area between the gas produced during the reaction and the target surface. Furthermore, if the reacting fluid solution does not contact the target surface for a period of time sufficient to allow reactive kinetics to occur, for example, if the solution flows across the surface at a high flow rate, gas will not form or may be produced in a suboptimal manner.

[0008] The main capillary force acting downward (F σ) and tractive force (F d ) and inertial force (F i ) and the combined force of the main buoyancy force (F B ) and gas instantaneous force (F M ) and, if present, capillary shear stress (F s ) combined forces overcome, the bubble detaches from the reaction surface.

[0009] The steady flow of electrolyte in a system is known to affect the efficiency of an electrolysis system. During electrolysis, which involves the formation of hydrogen and oxygen bubbles at the surfaces of two different electrodes, the formation of bubbles will hinder the reaction rate on the electrode surfaces until the bubbles spontaneously break capillary forces or are disengaged from the electrolyte flow across the electrodes. Conversely, a large electrolyte flow will reduce the available reaction time and significantly decrease the efficiency of the system.

[0010] Issues not addressed in known studies include the size distribution of gas bubbles as they depart during the electrochemical reaction, the loss of fluid efficiency, the relationship between bubble growth rate and flow pressure, the effect of capillary forces between the bubbles and the electrode, and, in particular, any periodicity of the fluid solution flow, the detrimental effect of the reaction rate on the flow rate used, or the ratio of gas bubble size to the available reaction surface area.

[0011] Flow pressure affects the rate at which bubbles grow: as pressure increases, the rate of bubble growth decreases proportionally, which increases the possibility of successfully timing the release of optimally sized bubbles with pulsating flow rates.

[0012] Fluid flowing in a curved channel experiences a higher fluid velocity on the inner curve of the channel relative to the fluid velocity on the outer curve of the channel. Thus, the curved channel experiences a lower fluid pressure on the inner curve of the channel relative to the fluid pressure on the outer curve. This pressure difference is formulated as:

[0013]

number

[0014] where R is the radius of the curve, V is the fluid velocity, and p is the fluid viscosity.

[0015] As a bubble grows in such a curved flow environment, a pressure difference across the bubble results, which creates a buoyancy force from high pressure to low pressure, which can reduce the amount of additional force required to break the capillary forces needed to detach the bubble from its reaction surface. [Means for solving the problem]

[0016] The present invention involves a novel method for reducing system energy requirements by manipulating the formation of gas bubbles on a reaction surface. A fluid associated with a desired chemical or electrochemical reaction periodically flows, or pulses, across the reaction surface at a frequency consistent with the average time required for a desired proportion of gas bubbles to grow to a specific diameter and at a specific fluid pressure as part of the reaction. The fluid flow rate used is sufficient to break the capillary forces of bubbles on the reaction surface at said specific diameter. During periods between periodic fluid flows or pulsations, the fluid either does not flow or is at a sufficiently low flow rate to allow for sufficient reaction rates.

[0017] Systems and methods are described herein for optimizing the flow rate, pulsation frequency, and duration of a flowing fluid, as well as optimizing fluid channel design features, with the goal of reducing the energy required to support a gaseous product reaction for any given fluid pressure and viscosity. Optimization of these features can be determined, in whole or in part, by calculating the reaction rate of the gaseous product to form bubbles on a surface, by systematic experimentation to identify the effect of adjusting each feature on energy input versus energy output, and by systematic control of the reaction by adjusting dynamically controllable input features to optimize energy output versus energy input.

[0018] In some embodiments, at least one of fluid pressure or fluid viscosity is determined. For example, one or more sensors placed in the fluid may provide measurements that may determine the pressure and / or viscosity of the fluid. A probability distribution of bubble sizes is then selected, and an optimal flow rate of the fluid across the surface required to detach the bubbles from the reaction surface is calculated based on the determined pressure and / or viscosity. The flow rate of the fluid across the reaction surface is then adjusted to achieve the optimal flow rate. In some cases, the flow rate of the fluid is adjusted in response to optimizing the measured amount of energy output for the measured amount of energy input.

[0019] The reaction surface on which the bubbles form can be a concavely curved surface in some embodiments. Fluid can be continuously pumped through a cavity or fluid channel beside and parallel to the direction of the curve of the concavely curved surface. The cavity or fluid channel has sufficient cross-sectional space to allow the fluid to flow in a direction parallel to the curved surface area, resulting in higher fluid velocities in areas of the cavity or fluid channel that are not closest to the reaction surface.

[0020] In some embodiments, adjusting the flow rate includes periodically pulsing the fluid across the reaction surface at an optimal flow rate. During the periodic pulsation, the rate of fluid flow is at or near zero velocity. The period of the pulsed fluid can be increased as the flow pressure increases at the reaction surface to match or compensate for the decrease in bubble growth rate within the increased flow pressure.

[0021] In some embodiments, the pulsation of the fluid is achieved by using a piston pump, a valve-actuated fluid channel, a peristaltic pump, or other system capable of cyclically pulsating the fluid.

[0022] In some embodiments, the flow rate is monitored by a flow meter at one or both of the inlet and / or outlet to the system.

[0023] In some embodiments, the timing of the fluid pulsation frequency is controlled by monitoring energy consumption in the form of electrical energy (volts, current, and watts) and thermal energy (kelvin) in proportion to the fluid pressure of the reaction.

[0024] The above and other characteristics, features, and advantages of the present disclosure will become apparent from the following detailed description taken in conjunction with the accompanying drawings, in which like reference characters refer to like parts throughout. [Brief explanation of the drawings]

[0025] [Figure 1] Shown are bubbles that increase in size as they detach from the reaction surface. [Figure 2] 1 is a cross-section of a fluid-contained compartment including a reaction surface that chemically or electrochemically generates gaseous bubbles and a flow rate that creates shear forces, according to some embodiments of the present disclosure. [Figure 3] 1 is a cross-section of a fluid-enclosed compartment including a reaction surface with a concave curve that chemically or electrochemically generates gaseous bubbles and a flow rate that creates both shear forces and additional buoyancy forces, according to some embodiments of the present disclosure. [Figure 4] 1 illustrates design considerations for a curved electrolyzer according to some embodiments of the present disclosure. [Figure 5] 1 is an exemplary electrolytic cell design showing fluid channels and curved reaction surface areas, according to some embodiments of the present disclosure. [Figure 6] 1 illustrates an example of an apparatus for producing gas from an electrolysis process, according to some embodiments of the present disclosure. [Figure 7] 1 is a flowchart depicting an exemplary process for optimizing fluid flow rate across a reaction surface by monitoring energy input and the energy content of the produced gas, according to some embodiments of the present disclosure. [Figure 8] 1 is a flowchart illustrating an example process for optimizing fluid pulsation frequency, according to some embodiments of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0026] The present disclosure is directed to a fluid-enclosed compartment that includes a reactive surface that chemically or electrochemically generates gaseous bubbles on the surface. The enclosed fluid is necessary for and contributes to a chemical or electrochemical reaction, such as an electrolyte. The reactive surface may consist of a catalyst that chemically reacts with the fluid, or the reactive surface may be an anode or cathode with a specific applied voltage and current required to electrochemically react the enclosed fluid, regardless of whether heat, radiation, or other relevant energy sources present in the electromagnetic spectrum need to be applied to the system to support the reaction at the reactive surface.

[0027] Referring to Figure 1, images are shown, to scale, of the formation and detachment of gas bubbles from a reaction surface. From left to right, 100 shows a gas bubble growing under conditions that required a relatively lower energy expenditure than 102, and 102 shows a gas bubble growing under conditions that required a relatively lower energy expenditure than 104. As can be seen in 100, the gas bubble growing on the reaction surface detaches at a smaller size than 102, and 102 also shows that the gas bubble growing on the reaction surface detaches at a smaller size than 104. The images in Figure 1 clearly demonstrate the energy expenditure advantages of small bubble size growing on a reaction surface.

[0028] Referring now to FIG. 2, a cross section of a fluid-enclosed compartment containing a reaction surface that chemically or electrochemically generates gaseous bubbles is shown, a type of reaction chamber. A bubble 200 is shown forming at the reaction surface 202. The entire area outside the bubble and above the reaction surface is composed of a fluid necessary to support a chemical or electrochemical reaction, such as electrolyte 203. The chemical or electrochemical reaction occurs at the interface between the gaseous bubble 200, the reaction surface 202, and the fluid 203. Also shown is a view of fluid 206 flowing from right to left. There are several forces on the bubble that affect how the bubble 200 detaches from the reaction surface 202.

[0029] Capillary force (Fσ ) 218, at the point of contact between the gaseous bubble 200, the reaction surface 202, and the required fluid 203, holds the bubble on the surface to support the reaction. This is sometimes called surface tension. Two downward forces are shown at 218, representing the combination of capillary forces that hold the bubble on the reaction surface. This is affected by the composition of the reaction surface, the composition of the gas in the bubble, and the characteristics of the fluid.

[0030] When the bubble starts to move upward in the buoyancy direction, the inertial force (F i )214, which is a downward force.

[0031] Also, when the bubble starts to move through the fluid 203, the drag force (F d ) 216 must also be overcome. This is a downward force and is primarily influenced by the viscosity of the fluid.

[0032] Buoyancy (F B ) 210 is an upward force on the dense fluid 203 proportional to the volume of the bubble 200 minus the weight of the bubble. It is based on the sum of hydrostatic forces distributed across the entire surface of the bubble, from top to bottom, such that the fluid-based pressure at the top of the bubble is slightly lower than the hydrostatic pressure at the bottom, resulting in a net upward force vector.

[0033] Gas momentum force (F M ) 212 occurs as the bubble grows and is based on the gas velocity and its associated moment, simultaneously expanding the bubble 200. The faster the bubble grows, the greater the velocity and force. As the bubble becomes anchored on the surface, the momentum force of the gas acts generally in a direction away from the reaction surface. A net vector force in the upward direction is shown.

[0034] When a bubble is subjected to a lateral force from the unidirectional flow of the surrounding fluid, the shear force (F s ) 208 exists. When a lateral force pushes against one side of the bubble, it creates a fulcrum-like condition that provides an upward force. This force increases as the fluid velocity increases.

[0035] The flow rate 206 travels from right to left across the reaction surface starting at the wavy line, provides the necessary fluids to support the reaction at the reaction surface, provides the shear forces mentioned above for bubble growth, circulates through a pipe, tube, or other section to a reservoir, tank, or other section 204, and then circulates back to the reaction surface. While the fluid is in the reservoir, tank, or other section 204, the fluid's chemistry can be analyzed and appropriate chemical or other treatments can be applied to the fluid.

[0036] The purpose is to provide sufficient shear force, and in some embodiments additional buoyancy, to dislodge the bubbles with optimal system efficiency through manipulation of flow rate.

[0037] In some embodiments, the reaction surface and fluid channels above the reaction surface are rigidly concavely curved in one dimension, and fluid flows across the reaction surface in the same direction of the concave curve of the fluid channel, with a height above the surface of the reaction surface that is at least 2.5 times the diameter of the calculated bubble size, consistent with a continuous flow rate for the optimal energy output-to-input ratio determined by the process described above. The goal is to create a larger pressure differential between the bottom of the bubble at the reaction surface and the top of the bubble due to the high flow rate at the top of the channel. This larger pressure differential contributes more to buoyancy, reducing the net fluid velocity across the reaction surface required to detach the bubble, and thus requiring less external energy to activate the fluid pump.

[0038] Similarly, referring now to FIG. 3, a cross section of a fluid-enclosed compartment containing a curved reaction surface for chemically or electrochemically generating gaseous bubbles, a type of reaction chamber, is shown. A bubble 300 is shown forming at reaction surface 302. The entire area outside the bubble and above the reaction surface is composed of a fluid necessary to support a chemical or electrochemical reaction, such as electrolyte 303. The chemical or electrochemical reaction occurs at the interface between gaseous bubble 300, reaction surface 302, and fluid 303. Also shown is a diagram of fluid 306 flowing from right to left. There are several forces on the bubble that affect the state at the point where bubble 300 detaches from curved reaction surface 302. These consist of the same forces noted in FIG. 2, with the addition of one additional force (320).

[0039] Capillary force (F σ ) 318, the point of contact between the gaseous bubble 300, the reaction surface 302, and the required fluid 303, holds the bubble on the surface to support the reaction. This is sometimes called surface tension. Two downward forces are shown at 318, representing the combination of capillary forces that hold the bubble on the reaction surface. This is influenced by the composition of the reaction surface, the bubble gas, and the characteristics of the fluid.

[0040] When the bubble starts to move upward in the buoyancy direction, the inertial force (F i )314, which is a downward force.

[0041] Also, when the bubble starts to move through the fluid 303, the drag force (F d ) 316 must also be overcome. This is a downward force and is primarily influenced by the viscosity of the fluid.

[0042] Buoyancy (F B ) 310 is an upward force on the dense fluid 303 proportional to the volume of the bubble 300 minus the weight of the bubble. It is based on the sum of hydrostatic forces distributed across the entire surface of the bubble, from top to bottom, such that the fluid-based pressure at the top of the bubble is slightly lower than the hydrostatic pressure at the bottom, resulting in a net upward force vector.

[0043] The additional buoyancy force (F c ) 320 is the upward force caused by the flow rate moving down the channel along the curved reaction surface 302, decreasing in radius from bottom to top, and correspondingly decreasing the calculated flow pressure from bottom to top. That flow pressure follows Equation 1 above, where R is the curve radius of the fluid at the point in the flow channel, V is the velocity of the fluid 306, and p is the viscosity of the fluid 306. This creates an additional flow pressure difference between the bottom and top of the bubble that would not exist if there was no radius in the fluid channel.

[0044] Gas momentum force (F M ) 312 occurs as the bubble grows and is based on the gas velocity and its associated moment, simultaneously expanding the bubble 300. The faster the bubble grows, the greater the velocity and force. As the bubble becomes anchored on the surface, the momentum force of the gas acts generally in a direction away from the reaction surface. A net vector force in the upward direction is shown.

[0045] When a bubble is subjected to a lateral force from the unidirectional flow of the surrounding fluid, the shear force (F s ) 308 exists. When a lateral force pushes against one side of the bubble, it creates a fulcrum-like condition that provides an upward force. This force increases as the fluid velocity increases.

[0046] The flow rate 306 travels from right to left across the curved reaction surface starting at the wavy line, provides the necessary fluids to support the reaction at the reaction surface, provides the shear forces for bubble growth as described above, circulates through a pipe, tube, or other section to a reservoir, tank, or other section 304, and then circulates back to the reaction surface. While the fluid is in the reservoir, tank, or other section 304, the fluid's chemistry can be analyzed and appropriate chemical or other treatments can be applied to the fluid.

[0047] 4, design considerations for an electrochemically driven system that generates gaseous bubbles grown on a reactive surface in a fluid are shown. A cross section of the curved system design shows a membrane 404 separating two electrodes at 402 and 406, and an electrolyte flow 410 across one of the electrodes 402.

[0048] Interface design considerations are also illustrated in cross-sectional edge 400 showing structure 416 supporting electrical connections at 418 and 420 from the outside to the inside of the fluid chamber, the same electrical connections treated with a non-reactive surface coating at 412 and 414 for use within the fluid chamber and further electrically connected to electrodes at 406 and 402. To support the reaction of the electrochemical system and help ensure separation of fluids and / or gases between the two reactive surfaces of the electrodes at 406 and 402, membrane 404 has a seal 422 between support structure 406 and one side of membrane 404, further ensuring separation of fluids and / or gases between the two reactive surfaces of the electrodes.

[0049] Design considerations for flow rate into the reaction chamber of system 408 are also shown at 428 as the reaction surface is viewed from above and channeled through support structure 426 to electrode 424. Fluid is distributed from a single channel inlet as at 428, which in this view traverses the reaction surface of electrode 424 from bottom to top, branching several times to present fluid at approximately the same pressure and flow rate across the entire bottom edge of electrode 424.

[0050] Referring now to Figure 5, an exemplary electrolytic cell is represented as a three-dimensional view showing curved support structures 500 having curved fluid channels incorporated therein and having a reaction surface or electrode 502 positioned between one curved structure 500 and another identical curved structure 504. It should be understood that the three-dimensional representation shown in Figure 5 is merely an illustrative example of a curved fluid channel in an electrolytic cell. Other designs are possible, including variations in support structures, dimensions, curve radii, etc., and all such variations are contemplated and included within the scope of the present disclosure.

[0051] Referring now to FIG. 6, a single-cell electrolyzer without support structures is shown, along with various system controls, measurements, fluid and gas flows, and system support processes. The heart of the electrolyzer is the combination of an anode, cathode, and membrane separator 600. The anode and cathode are connected to a potentiostat 601, which both provides electrical energy to support the electrochemical reaction in the electrolyzer and measures the electrical energy consumed by the electrolyzer. Electrolyte 602 is exposed to or pumped across the anode, in this illustration, from bottom to top. To support or enhance the electrochemical reaction, the fluid and electrolyzer can be heated at 604, and a thermometer 613 can be used to facilitate control of heater 604 and / or to measure the heat generated by the electrolyzer at the anode. To support or enhance the electrochemical reaction, fluid 602 can be irradiated by a source of electromagnetic energy 606 energized, controlled, and monitored by device 608. During the electrochemical reaction, the anode produces gas by-products, which may be solely or primarily oxygen, that are bubbled or decomposed into the fluid 602 .

[0052] The cathode produces primarily hydrogen gas, which is captured as gas 603, bubbled into the fluid, or decomposed. To support or enhance the electrochemical reaction, the gas, fluid, or electrolytic cell can be heated at 605, and a thermometer 614 can be used to facilitate control of heater 605 and / or to measure the heat generated by the electrolytic cell at the cathode. To support or enhance the electrochemical reaction, the gas or fluid 603 can be irradiated by a source of electromagnetic energy 607 energized, controlled, and monitored by device 608.

[0053] The electrolyte is stored in a reservoir, tank, or other section 609, where the fluid's chemistry can be analyzed and appropriate chemical or other treatments can be applied to the fluid. The electrolyte is pumped from the reservoir 609 using a pump 611, such as a piston pump, a valve-actuated pressurization system, a peristaltic pump, or other system capable of pulsating the fluid periodically. The electrolyte entering the electrolytic cell is monitored and controlled for flow rate 611 and pressure 612.

[0054] The electrolyte 602 exiting the anode side of the electrolytic cell is monitored and controlled for flow rate 616 and pressure 615 before the gas and liquid are separated at 617. The electrolyte separated from the gas is then sent to reservoir 609. The separated gas, which is primarily oxygen, is monitored and controlled by backpressure regulator 621 before being vented at 622 or used elsewhere. A portion of the separated gas, which is primarily oxygen, is sent through mass flow controller 623 before being analyzed by gas chromatograph or similar system 627.

[0055] The gas 603 or fluid exiting the cathode side of the electrolyzer is monitored and controlled for flow rate 619 and pressure 618 before the gas and liquid are separated at 620. The separated gas, which is primarily hydrogen, is monitored and controlled by a backpressure regulator 624 before being stored at 625 or transported elsewhere. A portion of the separated gas, which is primarily hydrogen, is sent through a mass flow controller 626 before being analyzed by a gas chromatograph or similar system 627.

[0056] The system controller 628 monitors and controls all inputs used by the electrolytic cell, including the potentiostat 601, electrolyte reservoir 609, pump 611, inlet electrolyte flow rate 611, and other consumers used by the electrolytic cell (606, 607) controlled and monitored by pressure gauge 12, anode heater 604, cathode heater 605, and other electromagnetic radiation sources (606, 607). The system controller 628 can be based on any suitable processing circuit and includes control and memory circuits, which can be located on a single integrated circuit or can be separate components. As referred to herein, processing circuitry should be understood to mean circuitry based on one or more microprocessors, microcontrollers, digital signal processors, programmable logic devices, field programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), etc., and can include multi-core processors (e.g., dual-core, quad-core, hexa-core, or any suitable number of cores). In some embodiments, the processing circuitry may be distributed across multiple separate processors or processing units, for example, multiple processing units of the same type (e.g., two Intel Core i7 processors) or multiple different processors (e.g., an Intel Core i5 processor and an Intel Core i7 processor). The system controller 628 adjusts the inputs based on the aforementioned input measurements to output measurements of electrical energy consumption 601, outlet gas pressure (616) and fluid flow rate (619), outlet gas pressure (615) and fluid pressure (618), and measurements of all gases analyzed by gas chromatograph 627. The system controller 628 may receive these measurements through wired or wireless connections. For example, the system controller 628 may include a transceiver or data bus for communicating with the various sensors using any suitable wired or wireless data protocol (e.g., Ethernet, USB, Wi-Fi, Bluetooth, etc.).

[0057] The minimum and maximum thresholds are set in the system controller 628 based on predetermined limits for pressure, flow rate, temperature, and energy consumption of the components and equipment used in the system. Given different fluid pressures of the gaseous product reactions targeted by the system, the control logic is scaled using fluid flow rates empirically derived from the process described below in conjunction with FIG. 7. During normal operation, the control logic involves the same process. If a pulsating fluid strategy is targeted for system operation, the control logic is scaled using fluid pulsation frequencies empirically derived from the process described below in conjunction with FIG. 8. During normal operation, the control logic involves the same process.

[0058] Referring now to FIG. 7, a system requires a predetermined calculation of the amount of energy input, such as voltage, current, heat, radiation, or other relevant energy sources present in the electromagnetic spectrum, that must be applied to the system to support a chemical or electrochemical reaction at the reaction surface as a measure of system efficiency. Such calculations may require consideration of the effect of fluid pressure on the energy input requirements, particularly if slow bubble growth is an objective of the system. It is also necessary to calculate the rate of consumption of the reactant fluid based on the net area of the reaction surface and convert this into a minimum fluid flow rate within the system to ensure that the reaction is not starved.

[0059] A chemical or electrochemical reaction is initiated in the reaction chamber (702) using a fluid flow rate consistent with the expected energy input to the reaction and the expected amount consumed by the reaction. The reaction surface is monitored for sufficient fluid using a level gauge, a capacitance sensor calibrated for level measurement, or by monitoring a thermal anomaly emanating from the reaction surface, which may indicate a lack of fluid in the reaction (704). If insufficient fluid is being delivered to the reaction surface (go to "No" at 704), the flow rate is increased (706). If sufficient fluid is being delivered to the reaction surface (go to "Yes" at 704), all energy inputs are monitored against an output related to the energy content of the gas produced, which may be derived from the volume and pressure of the gas produced (708). If the energy inputs and outputs do not stabilize (go to "No" at 708), some embodiments may add a waiting period; otherwise, the aforementioned monitoring continues at 704 and 708.

[0060] If the energy input and output rates stabilize (proceed to "Yes" at 708), a baseline ratio of energy output to energy input is recorded, and at 710, the fluid flow rate is increased, and the energy input and output rates are monitored for stability after the flow rate increase (712). If the energy input consumption does not stabilize relative to the energy output rate (proceed to "No" at 712), in some embodiments, a waiting period can be added. If the energy input consumption relative to the energy output rate stabilizes (proceed to "Yes" at 712), the flow rate is increased, and the ratio of energy output to energy input is compared to the previous record (714). If the energy ratio improves (proceed to "Improved" at 714), the fluid flow rate is increased (710) and monitoring continues. If the energy ratio worsens (proceed to "Worsened" at 714), the fluid flow rate is decreased (716), and the reaction surface is monitored for sufficient fluid before continuing the aforementioned process (704). If there is no change in the ratio (go to "No Change" at 714), then in some embodiments a waiting period can be added.

[0061] In some embodiments, a reaction system process begins by pulsing the fluid at a very high flow rate at a frequency that corresponds to the calculated bubble growth time, which in turn corresponds to the continuous flow rate of the optimal energy input to output ratio determined by the process described above. The pulsation period is determined experimentally, which involves monitoring the flow rate exiting the reaction surface or chamber before recirculation and setting the previously determined optimal continuous flow rate as the end of the fluid pulsation period. Due to fluid inertial delay between the end of pulsation and the measurement of the end flow rate, it may be necessary to decrease the pulsation period until the observed fluid flow rate exiting the reaction surface matches the optimal continuous flow rate for the system. Figure 8 is a flowchart representing an exemplary process for optimizing the frequency of pulsating fluid across a reaction surface. The same process as Figure 7 is followed, except that instead of increasing or decreasing the flow rate in some processes, the frequency of the high flow rate pulsations is increased or decreased.

[0062] In some embodiments, the pulsation of the fluid provides the starting conditions of FIG. 7 in terms of pulsating the fluid at a fixed frequency and fixed duration as described above and in FIG. 8, and the flow rate per pulse is optimized by following the remaining process in FIG. 7.

Claims

1. 1. A method for optimizing a gas-forming chemical or electrochemical reaction, comprising: Determining at least one of a pressure of a fluid or a viscosity of the fluid; selecting a probability distribution of bubble sizes; calculating an optimal flow rate of the fluid across the reaction surface required to cause bubbles to detach from the reaction surface with the selected probability distribution of bubble sizes based on the determining; adjusting the flow rate of the fluid across the reaction surface to the optimum flow rate; During the gas-forming chemical or electrochemical reaction, gas bubbles form on the reaction surface; The method wherein the fluid is necessary for a chemical or electrochemical reaction to form the gas.

2. further comprising optimizing the measured energy output for the measured energy input; The method of claim 1 , wherein the adjusting the flow rate of the fluid across the reaction surface is performed in response to optimizing the amount of energy output.

3. The reaction surface is a concave curved surface, and the method further comprises:

10. The method of claim 1, comprising continuously pumping the fluid through a cavity or fluid channel beside and parallel to the direction of the curve of the concave curved surface, the cavity or fluid channel also being concave in shape and having sufficient cross-sectional space to allow the fluid to flow in a direction parallel to the curved reaction surface area, thereby achieving higher velocities in areas of the cavity or fluid channel that are not closest to the reaction surface.

4. 2. The method of claim 1, wherein adjusting the flow rate of the fluid includes periodically pulsing the fluid across a reaction surface to form the bubbles at the optimal flow rate and detach the bubbles from the reaction surface, and wherein the flow rate during the periodic pulsation is at or near zero velocity.

5. 5. The method of claim 4, wherein the period of the pulsating fluid increases as the fluid pressure increases at the reaction surface to coincide with a decrease in bubble growth rate within the increased fluid pressure.

6. The method of claim 4 , wherein the pulsation of the fluid is accomplished using a piston pump.

7. The method of claim 4 , wherein the pulsation of the fluid is performed using a valve-actuated fluid channel.

8. The method of claim 4 , wherein the pulsation of the fluid is performed using a peristaltic pump.

9. 5. The method of claim 4, further comprising controlling the period of the pulsation of the fluid by monitoring energy consumption in the form of electrical and thermal energy in proportion to the fluid pressure.

10. further comprising monitoring the velocity of the fluid; The method of claim 1 , wherein the velocity of the fluid is monitored by a flow meter and at least one of a fluid inlet or a fluid outlet.

11. 1. A system for optimizing a gas-forming chemical or electrochemical reaction, comprising: a reaction surface at which gas bubbles are formed during the gas-forming chemical or electrochemical reaction; a fluid necessary for the chemical or electrochemical reaction that forms the gas; a control circuit; the control circuitry determining at least one of a pressure of a fluid or a viscosity of the fluid; selecting a probability distribution of bubble sizes; calculating an optimal flow rate of the fluid across the reaction surface required to cause bubbles to detach from the reaction surface with the selected probability distribution of bubble sizes based on the determining; adjusting the flow rate of the fluid across the reaction surface to the optimum flow rate; 1. A system configured to include:

12. The control circuit further comprises: configured to optimize a measured amount of energy output for a measured amount of energy input; 12. The system of claim 11, wherein the control circuit configured to adjust the flow rate of the fluid across the reaction surface is configured to adjust the flow rate in response to optimizing the amount of energy output.

13. The reaction surface is a concave curved surface, and the control circuit further comprises:

12. The system of claim 11, further comprising: continuously pumping the fluid through a cavity or fluid channel in a direction beside and parallel to the direction of the curve of the concave curved surface, the cavity or fluid channel also being concave in shape and having sufficient cross-sectional space to allow the fluid to flow in a direction parallel to the curved reaction surface area, thereby causing the fluid to have a higher velocity in areas of the cavity or fluid channel that are not closest to the reaction surface.

14. 12. The system of claim 11, wherein the control circuit configured to adjust the flow rate of the fluid further comprises periodically pulsing the fluid across the reaction surface to form the bubbles at the optimal flow rate and detach the bubbles from the reaction surface, wherein the flow rate during the periodic pulsation is at or near zero velocity.

15. 15. The system of claim 14, wherein the control circuit is further configured to increase the period of the pulsating fluid as the fluid pressure increases at the reaction surface to coincide with a decrease in bubble growth rate within the increased fluid pressure.

16. The system of claim 14 , wherein the pulsation of the fluid is accomplished using a piston pump.

17. The system of claim 14 , wherein the pulsation of the fluid is accomplished using a valve-actuated fluid channel.

18. The system of claim 14 , wherein the pulsation of the fluid is accomplished using a peristaltic pump.

19. 15. The system of claim 14, wherein the control circuitry further comprises controlling the period of the pulsation of the fluid by monitoring energy consumption in the form of electrical energy and thermal energy in proportion to the fluid pressure.

20. The control circuit is further configured to monitor the velocity of the fluid; The system of claim 11 , wherein the control circuitry monitors the velocity of the fluid using a flow meter and at least one of a fluid inlet or a fluid outlet.

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