Power system for space capsule or ship and control method thereof

Abstract

The invention discloses a power system for a space capsule or a ship and a control method of the power system. The power system is composed of a high-temperature working medium circulating system, a low-temperature working medium circulating system, a heat pump, an automatic controller and two cold boxes. The high-temperature working medium circulating system consists of a first liquid storage tank, a first liquid pump, a jet pump, an in-cabin heat exchanger, an out-cabin heat exchanger and a countercurrent heat exchanger; the warm working medium circulating system consists of a second liquid storage tank, a second liquid pump, a second heat exchanger, a cylinder expander and a generator; the heat pump is composed of an air compressor, a first heat exchanger and a refrigeration expansion machine. The automatic controller is used for automatically controlling the temperature, the pressure and the flow of each part to be kept at set values. The efficiency bottleneck of an existing Carnot cycle heat engine is 50%, the temperature of a Carnot cycle low-temperature heat source is reduced to-192 DEG C, the environment temperature can become a Carnot cycle high-temperature heat source, environment energy development is facilitated, and the Carnot cycle heat engine is applied to a space station to obtain a new power generation and refrigeration adjusting means and applied to a ship to obtain zero-carbon, distributed, free and free power.

Description

Technical Field

[0001] The present invention belongs to the field of power engineering, and in particular relates to a power system for a space capsule or a ship and a control method thereof. Background Art

[0002] The main power supply of the space station is solar panels + batteries. In the sunny area, the panels generate electricity and charge the batteries at the same time. In the backlit area, the batteries are used for power supply or hibernation. The photoelectric conversion efficiency of solar panels is up to 30%. In order to provide enough energy for the spacecraft, solar panels usually need to be very large. The 8 solar arrays of the International Space Station contain thousands of solar cells, covering an area half the size of a standard football field. Its array can generate 120 kilowatts of electricity. The panel array has a large area, relatively low energy density, and is easily damaged by space debris.

[0003] Heat dissipation in the space capsule is another important issue. The heat of the space station mainly comes from the sun. If the space station turns to the side facing the sun, the temperature may be as high as 120°C, while if it turns to the other side where the earth blocks the sun, the temperature may drop to minus 140 degrees. And because the space station rotates quickly, it is equivalent to experiencing more than a dozen sunrises and sunsets in a day, and the temperature changes are very drastic, but heat dissipation in the space capsule is an important issue. There is heat from the sun shining into the cabin, heat from the astronauts' own body temperature, heat from the electronic equipment in the cabin, and all the electricity used by the space station are all converted into equivalent heat and dissipated in the cabin. These three parts of heat continue to accumulate in the cabin, causing the temperature in the cabin to continue to rise, endangering personal safety and equipment operation. The temperature control of the space station is divided into passive temperature control and active temperature control. Passive temperature control is insulation. The cabin of the space station has a high reflective layer of multi-layer insulation (MLI). The reflective layer is made of aluminum polyester film and polyester. Except for a few portholes and hatches, they are all covered. These materials ensure that most of the sunlight is reflected, thereby isolating the heat outside, keeping the temperature inside the cabin suitable for astronauts to live in and the equipment to function normally. This highly reflective layer is also responsible for protecting astronauts from low temperatures when the space station flies to the back of the earth. The function of the active thermal control system is to "heat dissipation", also known as ATCS, which is mainly composed of closed-loop pipes. Through the refrigerant - liquid ammonia, the waste heat generated by the space station is radiated to the external radiator plate. Many of the space station's extravehicular operations are to repair cooling system failures.

[0004] The general ship power mainly relies on diesel engines, while the power of large ships such as aircraft carriers relies on boiler steam Rankine cycle power generation systems or nuclear-powered steam Rankine cycle power generation systems. Nuclear power plants are large in scale, difficult to control, and have nuclear pollution. Conventional power requires a large amount of fuel, has a slow start-up speed, low thermal efficiency, and serious environmental pollution.

[0005] In the process of continuously improving the temperature of high-temperature heat sources, the thermal power specialty has reached a temperature of 620°C for the Rankine cycle of thermal power, 1250°C for the Brayton cycle of gas turbines, 3000°C for the high-temperature heat source of magnetohydrodynamic power generation, and the highest temperature of controlled nuclear fusion has reached tens of millions or even hundreds of millions of degrees Celsius. As the temperature of high-temperature heat sources continues to increase, the efficiency of thermal power systems has continued to increase from 3%-5% of early steam engines. Currently, the efficiency of the ultra-supercritical Rankine cycle of thermal power is close to 50%, and the efficiency of the Brayton cycle of supercritical CO2 reaches 50% when the temperature of the high-temperature heat source exceeds 650°C.

[0006] According to the first step of the Carnot cycle efficiency formula η=(Q1-Q2) / Q1, the inventors believe that in addition to the traditional technical route of continuously increasing the temperature of the high-temperature heat source to improve the thermal efficiency of the power cycle system, a second technical route can also be taken: reducing the amount of heat discharged by the condensation heat Q2 of the power cycle system to improve the efficiency of the power cycle system, or making the discharge of the condensation heat Q2 of the power cycle system zero so that the efficiency of the power cycle system is equal to 1. Based on the conception and exploration of this new technical route, it is urgent to propose a dual-medium low-temperature cycle power system and its control method. Summary of the invention

[0007] Based on the above new technical route and research, the present invention reduces the exhaust steam heat of the power cycle system used for the space capsule or ship, and provides a power system for the space capsule or ship and a control method thereof.

[0008] In order to achieve the above tasks, the present invention adopts the following technical solutions:

[0009] On the one hand, the present invention provides a power system for a space capsule, which is composed of a high-temperature working fluid circulation system, a low-temperature working fluid circulation system, a set of heat pumps, an automatic controller and two cold boxes; wherein:

[0010] The high-temperature working medium circulation system is composed of at least one first liquid storage tank CYG1, a first liquid pump YB1, a jet pump SLB, a group of in-cabin heat exchangers NHRQ, a group of out-cabin heat exchangers WHRQ, and a group of countercurrent heat exchangers NLHRQ; wherein, the liquid working medium outlet of the first liquid storage tank CYG1 is connected in series to the inlet and outlet of the first liquid pump YB1, to the inlet and outlet of the jet pump SLB, to the inlet and outlet of the in-cabin heat exchanger HRQ and the out-cabin heat exchanger WHRQ after being connected in parallel, to the high-temperature channel inlet and outlet of the countercurrent heat exchanger NLHRQ, and to the inlet of the first liquid storage tank CYG1, and the air intake of the jet pump SLB is connected to the gas outlet of the first cold box LX1;

[0011] The low-temperature working medium circulation system is composed of at least one second liquid storage tank CYG2, a second liquid pump YB2, a second heat exchanger HR2, a two-stroke cylinder expander QG for expansion work and compression exhaust and a connected generator; wherein the liquid working medium outlet of the second liquid storage tank CYG2, the inlet and outlet to the second liquid pump YB2, the inlet and outlet of the second heat exchanger HR2, the inlet and outlet to the low-temperature channel of the countercurrent heat exchanger NLHRQ, the inlet and outlet to the cylinder expander QG, and the inlet to the low-temperature liquid storage tank CYG2 are connected in series in sequence; the second heat exchanger HR2 is installed at the bottom of the first liquid storage tank CYG1.

[0012] The boiling point temperature of the working fluid stored in the first liquid storage tank CYG1 needs to be higher than the boiling point temperature of the working fluid in the second liquid storage tank CYG2;

[0013] Heat pump: It consists of a compressor YQJ, a first heat exchanger HR1 and a refrigeration expansion machine PZ; wherein, the air outlet of the second liquid storage tank CYG2, the inlet and outlet of the compressor YQJ, the inlet and outlet of the first heat exchanger HR1, the inlet and outlet of the refrigeration expansion machine PZ, and the inlet of the second liquid storage tank CYG2 are connected in series in sequence, and the compressor YQJ, the refrigeration expansion machine PZ and its driving motor operate coaxially; an exhaust port To LX is provided on the top of the first liquid storage tank CYG1, and the saturated air generated by the heat of the heat pump in the first liquid storage tank CYG1 is discharged from the exhaust port To LX on the top of the first liquid storage tank CYG1 to the second cold box LX2; the first heat exchanger HR1 is installed at the bottom of the first liquid storage tank CYG1;

[0014] The countercurrent heat exchanger NLHRQ is installed in the first cold box LX1; the first liquid storage tank CYG1, the second liquid storage tank CYG2, the first liquid pump YB1, the second liquid pump YB2, the compressor YQJ, the refrigeration expander PZ and the cylinder expander QG are all installed in the second cold box LX2. The top of the second cold box LX2 is connected to the bottom of the first cold box LX1;

[0015] Automatic controller KZQ is used to automatically control the temperature, pressure, flow and other parameters of each part of the system to maintain them at the set values.

[0016] In one aspect, the present invention provides a control method for a power system of a space capsule. The method is based on the power system of the space capsule of the present invention and specifically comprises the following steps:

[0017] The first liquid pump YB1 in the automatic control high-temperature working medium circulation system extracts a certain amount of liquid working medium from the first liquid storage tank CYG1 and sends it to the jet pump SLB. The jet pump SLB extracts a certain amount of gaseous working medium from the first cold box LX1, and sends the mixed working medium to the parallel circuit of the cabin heat exchanger NHRQ and the cabin heat exchanger WHRQ, where it is heated and vaporized to become normal-temperature working medium gas. The normal-temperature working medium gas then flows into the high-temperature channel of the countercurrent heat exchanger NLHRQ, transfers the heat to the low-temperature channel in the countercurrent heat exchanger NLHRQ, cools down in the high-temperature channel of the countercurrent heat exchanger NLHRQ, and liquefies and flows into the first liquid storage tank CYG1, completing the cycle.

[0018] The second liquid pump YB2 of the automatic control low-temperature working medium circulation system extracts liquid working medium from the second liquid storage tank CYG2, sends it through the low-temperature channel of the second heat exchanger HR2 and the countercurrent heat exchanger NLHRQ to absorb heat and gasify into high-pressure steam, and the exhaust steam after expansion and work by the cylinder expander QG flows into the second liquid storage tank CYG2 to complete the cycle;

[0019] The compressor YQJ of the automatic control heat pump extracts the working medium exhaust steam in the second liquid storage tank CYG2, compresses and heats it, and then flows through the first heat exchanger HR1 arranged in the first liquid storage tank CYG1, transfers the exhaust steam heat to the first liquid storage tank CYG1, and then liquefies and flows back to the second liquid storage tank CYG2 through the refrigeration expansion machine PZ;

[0020] Automatic controller KZQ is used to control the pressure, temperature, flow and other parameters of each part of the system to run at the preset values.

[0021] In a third aspect, the present invention provides a power system for ships, which is obtained by replacing the outboard heat exchanger WHRQ and the inboard heat exchanger NHRQ in the power system of a space capsule with a cabin evaporator CQHQ using water as an intermediate medium as a heat source and an air heat exchanger KQHRQ having a hydrophobic coating on the surface.

[0022] Furthermore, the cabin evaporator CQHQ is obtained by arranging a closed cabin at the bottom below the waterline of the hull, arranging a tubular heat exchanger at the top of the closed cabin, and injecting a low-boiling-point working medium into the closed cabin.

[0023] In a fourth aspect, the present invention provides a control method for a power system for a ship, which is based on the above-mentioned power system for a ship, and replaces the outboard heat exchanger WHRQ and the inboard heat exchanger NHRQ in the control method for the power system of a space capsule with a cabin evaporator CQHQ with water as the intermediate medium of the heat source and an air heat exchanger KQHRQ with a hydrophobic coating on the surface.

[0024] In a fifth aspect, the present invention provides a power system for a space capsule, which is a power system for a space capsule as described in claim 1, wherein a group of heat absorption heat exchangers are connected in series between the air intake of the heat pump compressor YQJ and the outlet of the refrigeration expansion machine PZ and are arranged on the top of the second liquid storage tank, and a third circulating working fluid is filled in the heat pump circulation system; and the connection between the compressor YQJ and the second liquid storage tank is disconnected.

[0025] In a sixth aspect, the present invention provides a power system for a space capsule, wherein the cylinder expander QG in the power system for a space capsule described in claim 1 is replaced by a turbine expander, a screw expander or a centripetal expander.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] The present invention relatively reduces the exhaust heat of the working fluid gas through the selection of circulating working fluids and the low-temperature circulation of the working fluids. The condensation heat of the exhaust steam is recovered by the heat pump. The power system of the dual-working fluid low-temperature circulation no longer discharges the exhaust heat to the environment, so that the theoretical thermal efficiency of the entire power cycle system is equal to 1. The power cycle system can draw heat energy from environmental heat such as water and air at ambient temperature as a heat source to drive the power system, which can achieve revolutionary progress in zero-carbon, distributed, free, free power and electricity. When used in a sealed environment of a space capsule, it can draw heat from the air in the cabin to generate electricity, and at the same time has a good regulating effect on the air temperature in the cabin. It can be used as a power generation device in the space cabin and as a temperature regulating device in the cabin. It can also draw heat from seawater and the ambient atmosphere and convert it into power, providing ships with zero-carbon, free and free power. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 Schematic diagram of dual-fluid cycle power system for space capsule;

[0029] Figure 2 Schematic diagram of the dual-fluid cycle power system PH;

[0030] Figure 3 PH diagram of hydrogen working fluid in dual working fluid cycle power system;

[0031] Figure 4 Schematic diagram of the cabin carburetor with the bottom of the hull used as the intermediate medium.

[0032] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. DETAILED DESCRIPTION

[0033] The power system for a space capsule or a ship and the control method thereof of the present invention are further explained below in conjunction with the accompanying drawings.

[0034] like Figure 1As shown, the present invention provides a dual-working fluid circulation power system for a space capsule, which is composed of a high-temperature working fluid circulation system, a low-temperature working fluid circulation system, a group of heat pumps, an automatic controller and two cold boxes; wherein:

[0035] A high-temperature working medium circulation system (hereinafter referred to as system I): consists of at least one first liquid storage tank CYG1, a first liquid pump YB1, a jet pump SLB, a group of in-cabin heat exchangers NHRQ, a group of out-cabin heat exchangers WHRQ, and a group of countercurrent heat exchangers NLHRQ; wherein, the liquid working medium outlet of the first liquid storage tank CYG1 is connected in series to the inlet and outlet of the first liquid pump YB1, to the inlet and outlet of the jet pump SLB, to the inlet and outlet of the in-cabin heat exchanger HRQ and the out-cabin heat exchanger WHRQ after being connected in parallel, to the high-temperature channel inlet and outlet of the countercurrent heat exchanger NLHRQ, and to the inlet of the first liquid storage tank CYG1, and the air intake of the jet pump SLB is connected to the gas outlet of the first cold box LX1;

[0036] Low-temperature working fluid circulation system (hereinafter referred to as system II): consists of at least one second liquid storage tank CYG2, a second liquid pump YB2, a second heat exchanger HR2, a two-stroke cylinder expander QG for expansion work and compression exhaust and a connected generator; wherein, the liquid working fluid outlet of the second liquid storage tank CYG2, the inlet and outlet to the second liquid pump YB2, the inlet and outlet of the second heat exchanger HR2, the inlet and outlet to the low-temperature channel of the countercurrent heat exchanger NLHRQ, the inlet and outlet to the cylinder expander QG, and the inlet to the low-temperature liquid storage tank CYG2 are connected in series in sequence; the second heat exchanger HR2 is installed at the bottom of the first liquid storage tank CYG1.

[0037] The boiling point temperature of the working fluid stored in the first liquid storage tank CYG1 must be higher than the boiling point temperature of the working fluid in the second liquid storage tank CYG2 to ensure that the working fluid of system I can be cooled and liquefied in the countercurrent heat exchanger NLHRQ;

[0038] Heat pump: It consists of a compressor YQJ, a first heat exchanger HR1 and a refrigeration expansion machine PZ; wherein, the air outlet of the second liquid storage tank CYG2, the inlet and outlet of the compressor YQJ, the inlet and outlet of the first heat exchanger HR1, the inlet and outlet of the refrigeration expansion machine PZ, and the inlet of the second liquid storage tank CYG2 are connected in series in sequence, and the compressor YQJ, the refrigeration expansion machine PZ and its driving motor operate coaxially; an exhaust port To LX is provided on the top of the first liquid storage tank CYG1, and the saturated air (-192℃) generated by the heat of the heat pump in the first liquid storage tank CYG1 is discharged from the exhaust port To LX on the top of the first liquid storage tank CYG1 to the second cold box LX2; the first heat exchanger HR1 is installed at the bottom of the first liquid storage tank CYG1 for heat release.

[0039] The countercurrent heat exchanger NLHRQ is installed in the first cold box LX1; the first liquid storage tank CYG1, the second liquid storage tank CYG2, the first liquid pump YB1, the second liquid pump YB2, the compressor YQJ, the refrigeration expander PZ and the cylinder expander QG are all installed in the second cold box LX2. The top of the second cold box LX2 is connected to the bottom of the first cold box LX1.

[0040] The automatic controller KZQ is used to control the cycle power system of the present invention.

[0041] The products selected for each part of the present invention are as follows:

[0042] The automatic controller KZQ adopts the existing controller.

[0043] The liquefaction temperature of the working fluid selected in the first liquid storage tank CYG1 is lower than the ambient temperature. The liquid storage tank adopts a low-temperature container. Insulation measures need to be taken according to the selected working fluid. A Dewar tank is preferred. The first liquid pump YB1 adopts a low-temperature liquid pump.

[0044] The jet pump SLB has two inlets and one outlet, the two inlets are a liquid inlet and an air intake, and the jet of the liquid working fluid in the jet pump SLB is used to absorb gas; the cabin heat exchanger NHRQ is an air heat exchanger installed in the space capsule, and absorbs heat in the air by circulating the cabin air; the cabin heat exchanger WHRQ is a heat exchanger installed outside the space capsule to absorb solar energy, and the two sets of internal and external heat exchangers are operated in parallel through valves, and the two sets of heat exchangers can be selectively switched or operated in parallel; the countercurrent heat exchanger NLHRQ adopts the countercurrent heat exchanger in the prior art, and has a high-temperature channel and a low-temperature channel, wherein the high-temperature channel is connected to system I, and the low-temperature channel is connected to system II, the high-temperature channel decreases in temperature from top to bottom to liquefy the working fluid, and the low-temperature channel absorbs heat from bottom to top to vaporize the high-pressure liquid working fluid in system II to obtain expansion work, and the working fluids in the high-temperature channel and the low-temperature channel flow in the heat exchanger in reverse to exchange heat;

[0045] The second liquid storage tank CYG2 stores the working fluid of system II, which is subject to certain pressure fluctuations during operation. It is a low-temperature container and needs to take insulation measures, such as a Dewar tank; in order to enable system II to obtain a higher circulation power, the second liquid pump YB2 needs to provide a higher outlet pressure, which is a low-temperature and high-pressure liquid pump; the second heat exchanger HR2 is arranged in the first liquid storage tank and is connected in series to the outlet of the second liquid pump YB2, and is used to adjust the working fluid temperature of the circulating working fluid of system II before entering the countercurrent heat exchanger NLHRQ, so as to ensure that the working fluid of system I can be liquefied in the countercurrent heat exchanger NLHRQ without solidification; the countercurrent heat exchanger NLHRQ has a high-temperature channel and a low-temperature channel, the high-temperature channel is connected in series to system I, and the low-temperature channel is connected in series to system II; the cylinder expander QG is a two-stroke cylinder expander with expansion work and compression exhaust;

[0046] The heat exchanger HR1 adopts a condensing heat exchanger. The compressor YQJ extracts saturated gas of the working medium from the second liquid storage tank CYG2, compresses and raises the temperature higher than the temperature of the working medium in the first liquid storage tank CYG1, releases heat through the first heat exchanger HR1, and then flows back to the second liquid storage tank CYG2 after reducing the pressure and temperature and liquefying through the refrigeration expander PZ; the heat pump belongs to the existing technology and will not be described in detail;

[0047] The automatic controller KZQ is used to automatically control the temperature, pressure, flow and other parameters of each part of the system to maintain the set values. It is easy to implement using existing technology and will not be described in detail in the present invention.

[0048] The present invention provides a control method for a power system of a space capsule, which specifically comprises the following steps:

[0049] The first liquid pump YB1 in the automatic control system I extracts a certain amount of liquid working medium from the first liquid storage tank CYG1 and sends it to the jet pump SLB. The jet pump SLB extracts a certain amount of gaseous working medium from the first cold box LX1, and sends the mixed working medium to the parallel circuit of the cabin heat exchanger NHRQ and the cabin heat exchanger WHRQ, and heats and vaporizes it to become normal temperature working medium gas. The normal temperature working medium gas then flows into the high temperature channel of the countercurrent heat exchanger NLHRQ, transfers the heat to the low temperature channel of the countercurrent heat exchanger NLHRQ, cools down and liquefies in the high temperature channel of the countercurrent heat exchanger NLHRQ, and flows into the first liquid storage tank CYG1, completing the cycle.

[0050] The second liquid pump YB2 of the automatic control system II extracts liquid working medium from the second liquid storage tank CYG2, sends it through the low-temperature channel of the second heat exchanger HR2 and the countercurrent heat exchanger NLHRQ to absorb heat and gasify into high-pressure steam, and the exhaust steam after expansion and work by the cylinder expander QG flows into the second liquid storage tank CYG2, completing the cycle;

[0051] The compressor YQJ of the automatic control heat pump extracts the working medium exhaust steam in the second liquid storage tank CYG2, compresses and heats it, and then flows through the first heat exchanger HR1 arranged in the first liquid storage tank CYG1, transfers the exhaust steam heat to the first liquid storage tank CYG1, and then liquefies and flows back to the second liquid storage tank CYG2 through the refrigeration expansion machine PZ;

[0052] The automatic controller KZQ is a controller of the prior art, which controls the pressure, temperature, flow and other parameters of each part of the system to run at preset values.

[0053] Figure 2It is a PH schematic diagram of the power system for the space capsule of the present invention, line I is the saturation line of the circulating working fluid of system I, lines 123 are the circulation lines of the working fluid in system I, 1-2 is the pressurization process of the first liquid pump YB1 and the jet pump SLB, 2-3 is the heat absorption process of the working fluid, and 3-1 is the heat release process of the working fluid; line II is the saturation line of the working fluid of system II, lines 4567 are the circulation lines of the working fluid in system II, 4-5 is the pressurization line of the liquid pump 2, 5-6 is the isobaric heating line of the working fluid, and 6-7 is the isentropic expansion line of the working fluid; line III is the circulation line of the heat pump working fluid, 7-8 is the pressurization process of the heat pump compressor, 8-9 is the heat release process of the heat pump system heat exchanger HR to system I, and 9-10 is the isentropic expansion process of the refrigeration expander PZ.

[0054] Figure 3 This is a PH diagram of hydrogen working medium in the power system of the space capsule of the present invention. The base map is provided by Ref Prop software. 4567 in the figure is the power cycle line of hydrogen. By looking up the parameters of each point on the cycle line in the figure, combined with Figure 1 , Figure 2 , the operation control of the system I using air as the circulating working medium and the system II using hydrogen as the circulating working medium in a space capsule with an internal temperature of 30° C. is described as follows (for example only and not to limit the present invention):

[0055] 1. In system I, the first liquid pump YB1 is automatically controlled to extract liquid air (-192°C) in the first liquid storage tank CYG1 and send it to the jet pump SLB. The jet pump SLB extracts air from the first cold box LX1 and mixes it and sends it to the cabin heat exchanger NHRQ. The external heat exchanger WHRQ is in a closed state. The circulating air working medium absorbs heat from the cabin heat exchanger NHRQ. The temperature difference between the cabin air and the circulating working medium air on the cabin heat exchanger NHRQ is set to 15°C. Then, the temperature of the circulating working medium outlet of the cabin heat exchanger NHRQ is 15°C. After entering the high-temperature channel of the countercurrent heat exchanger NLHRQ to release heat and cool down, it flows into the first liquid storage tank CYG1 to complete the cycle.

[0056] 2. In system II, the second liquid pump YB2 is automatically controlled to extract liquid hydrogen from the second liquid storage tank CYG2, pressurize it to 7.8MPa, and flow into the low-temperature channel of the countercurrent heat exchanger NLHRQ, absorbing heat from bottom to top and heating up to gasify. When the air temperature at the inlet of the high-temperature channel of the countercurrent heat exchanger NLHRQ is 15℃, the temperature difference with the outlet of the low-temperature channel is set at 15℃. The hydrogen at the outlet of the low-temperature channel is 0℃ and the pressure is 7.8MPa. It flows into the cylinder expander QG to expand and do work. The exhaust steam after doing work flows into the second liquid storage tank CYG2 to complete the cycle; Figure 3 The parameters of each node of the power cycle system are listed in Table 1:

[0057] Table 1 Power system parameters of dual working fluid cycle

[0058]

[0059] If the cylinder expander of the power cycle system is connected to a generator set, the power generation capacity can be obtained:

[0060] W=H 67 / η pz ×η=2800×0.95=2520kW;

[0061] According to the maximum specific enthalpy of the power cycle system of 3600kJ, the air flow rate of the air liquefaction system is calculated as follows:

[0062] When the circulating air temperature is 15℃, the density is 1.205kg / m3, the specific heat capacity Cp is 1.005kj / kg.℃, the boiling point of liquid air is -192.℃, the density is 960kg / m3, the heat of vaporization is 196.742kJ / kg; the heat released before liquefaction of each kg of air is the sum of the specific heat and the heat of vaporization:

[0063] Qc+Qy=(20+192)×1.005+196.742=409.8kJ / kg;

[0064] The air flow rate for heat balance with the power system is:

[0065] S = [3600-(1000×7.8×1 / 960)] / 409.8 = 8.76 kg / s (wherein: theoretical compression work of the liquid pump Np = (1000×7.8×1 / 960) = 8.125 kW; actual compression work: N = 8.125 / 0.85 = 9.6 kW);

[0066] 3. Heat pump system: The heat pump system consists of a compressor YQJ, a first heat exchanger HR1, and a refrigeration expansion machine PZ. The compressor YQJ extracts the exhaust steam from the second liquid storage tank CYG2, compresses it and heats it up, and then sends it to the first heat exchanger HR1 to release heat to the liquid air in the first liquid storage tank CYG1. The exhaust steam is cooled and liquefied by the refrigeration expansion machine PZ, and then flows into the second liquid storage tank CYG2 to complete the heat pump cycle. The temperature of the second liquid storage tank CYG2 is -253°C (20k), the exhaust steam temperature is -220 (53k), and the liquid air temperature in the liquid tank I CYG1 is -192°C (81k). The refrigeration coefficient of the heat pump is: COPc = 53 / (81-53) = 1.89.

[0067] The heat pump outputs heat to liquid air: Qc = H 74 +H 74 / COPc=800+800 / 1.89=1223 kJ / s;

[0068] The theoretical power consumption of compressor YQJ is Nc = (H 74 / COPc)=800 / 1.89=423kW;

[0069] The actual power consumption of compressor YQJ is Nc'=Nc / η=800 / 1.89 / 0.42=1008kW;

[0070] The power recovery of the refrigeration expander PZ is Np = Nc × ηp = 423 × 0.9 = 380 kW;

[0071] The total energy consumption of the entire heat pump system is: Nc'-Np = 1008-470 = 628kW;

[0072] The heat absorbed by the heat exchanger HR at the outlet of the second liquid pump YB2 is:

[0073] Q HR =Cp×(T5'-T5)=14.27×(61-20)=585.07kJ;

[0074] The total heat received by the first liquid storage tank is: Qc-Q HR =1223-585.07=637.93kJ;

[0075] 4. Balance calculation of heat pump output heat and air liquefaction volume:

[0076] The liquefied air flow rate balanced with the power system is 8.76 kg / s; the heat required for all gasification is:

[0077] 196.742×8.76=1723.5kJ / s;

[0078] The total heat received by the first liquid storage tank CYG1 is 637.93 kJ, and the amount of liquid air is sufficient to absorb the heat output by the heat pump;

[0079] 673.93÷1723.5=39%.

[0080] Low temperature cold air output: 8.76×39%=3.4kg / s;

[0081] Therefore, 39% of the liquid air generated in the air liquefaction process is vaporized by absorbing the heat pump, and the vaporized low-temperature (-192°C) air supplies cooling to the system cold box, and then participates in the cycle of system I;

[0082] Energy efficiency of system power generation: β = power generation / (air compression work + liquid pump work + heat pump consumption)

[0083] =2520 / (1000×0.7×8.76÷960+9.6+628)=3.9;

[0084] When the total power input of the air compressor, liquid pump and heat pump in the system is 1kW, 3.9kW of electricity can be produced.

[0085] The power system for a space capsule of the present invention is essentially to use the air working medium of system I to circulate, so that the air in the cabin is used as a high-temperature heat source of the Carnot cycle, and the liquefied liquid air is used as a low-temperature heat source of the Carnot cycle, providing two heat sources for the Rankine cycle of system II with hydrogen as the working medium, and the liquefied air is used to recover the exhaust steam heat of system II through a heat pump to liquefy the exhaust steam, so that the Rankine cycle of hydrogen at low temperature can be realized; the whole system is coupled with a countercurrent heat exchanger NLHRQ, the air working medium circulation process of system I obtains a cooling channel for cooling and liquefaction in the countercurrent heat exchanger, and the power cycle system of system II obtains a channel for heating and gasifying hydrogen in the countercurrent heat exchanger, thereby achieving the control target under the new technical route, and shifting the low-temperature area of ​​the Carnot cycle in the prior art from the ambient temperature to the liquid hydrogen temperature zone of 20k;

[0086] The power system for the space capsule of the present invention can fully recover the exhaust heat of the power cycle, and its theoretical thermal efficiency is equal to 1; it does not absorb heat from outside the cabin, but only relies on the sum of the heat transfer from the insulation layer in the space cabin, the heat emitted by human activities, and the equivalent heat converted by power consumption, which are all absorbed and converted into electrical energy by the air heat exchanger NHRQ in the cabin. It can also self-circulate in a dark area for a long time without sleep; the power generation of the sum of the three parts of heat is greater than the power consumption in the cabin, and the excess power can be stored in the battery, and lights, microwave transmitters, electromagnetic transmitters, laser transmitters, etc. can be set outside the space capsule to radiate the excess power generation to space, which has better heat dissipation effect than the existing technology through cooling circuits and radiation heat sinks, higher reliability, faster adjustment speed, and easier implementation; keep the three parts of heat in the cabin consistent with the power generation, the cabin temperature can be kept constant, if the cabin temperature is to be reduced, the power generation is increased, if the cabin temperature is to be increased, the power generation is reduced, and the cabin temperature can be kept constant or adjusted while generating electricity, and the radiation heat sink of the existing technology outside the cabin can be omitted. It provides a new power generation method and cabin temperature regulation technology for space technology.

[0087] If you want to increase the power of the microwave transmitter, electromagnetic transmitter and laser transmitter installed outside the cabin, you can turn on the cabin heat exchanger WHRQ to absorb more heat from the outside and increase the power generation;

[0088] The heat exchange efficiency of the extravehicular heat exchanger WHRQ can reach 90% according to existing technology. Compared with the 30% conversion efficiency of photovoltaic panels, the area of ​​the extravehicular heat exchanger required to absorb the same amount of energy from outside the cabin is 1 / 3 of that of the photovoltaic panels. The extravehicular heat exchanger's ability to withstand the damage of space debris is higher than that of photovoltaic panels.

[0089] The present invention provides a power system for ships, which replaces the outboard heat exchanger WHRQ and the inboard heat exchanger NHRQ in the power system for a space capsule of the present invention with a cabin evaporator CQHQ using water as an intermediate medium as a heat source and an air heat exchanger KQHRQ having a hydrophobic coating on the surface in the prior art.

[0090] The cabin vaporizer CQHQ for the intermediate medium of the ship is obtained in the following way: a closed cabin is set at the bottom below the waterline of the hull, a tubular heat exchanger is set at the top of the closed cabin, and a low-boiling-point working medium, such as propane, is injected into the closed cabin.

[0091] Figure 4 It is a schematic diagram of the principle of using part of the closed cabin space below the waterline at the bottom of the hull as a cabin vaporizer. A tubular heat exchanger is arranged on the top of the closed cabin, and some low-boiling-point working fluids, such as propane, are filled in the bottom. The top heat exchanger absorbs the heat of the low-boiling-point working fluid steam in the cabin vaporizer CQHQ, causing the low-boiling-point working fluid to condense and fall. The seawater heats the liquid low-boiling-point working fluid at the bottom to vaporize it. The low-boiling-point working fluid forms convection heat transfer in the cabin vaporizer CQHQ, and transfers the heat of the seawater to the circulating working fluid in the heat exchanger through the convection of the low-boiling-point working fluid.

[0092] When the dual-fluid cycle power system DLXT is used for ships, nodes 2 and 3 in the power system are connected in parallel with the cabin vaporizer CQHQ and the air heat exchanger KQHRQ outside the ship, and can be switched between the cabin vaporizer CQHQ and the air heat exchanger KQHRQ according to the situation; when the dual-cycle working fluids of the power system DLXT still use air and hydrogen, at normal seawater temperature (the annual water temperature of the South China Sea is 22-29°C) and ambient temperature, the dual-fluid cycle power system can obtain a good cycle according to the control method of claim 2, and in order to save space, it will not be repeated.

[0093] There is still a lot of room for research on the combination of different working fluids in dual-working fluid cycle power systems. Current research believes that air and hydrogen are used as the working fluids of the dual-working fluid cycle system, helium is used as the cooling working fluid, and the lowest temperature in the circulation system is liquid helium (4.2K) close to 0k, which maximizes the power cycle temperature range and can effectively draw heat from the ambient temperature heat source to drive the power system cycle.

[0094] Preferably, a group of heat absorbing heat exchangers are connected in series between the air intake port of the compressor YQJ in the heat pump and the outlet of the refrigeration expander PZ and arranged on the top of the second liquid storage tank, and a third circulating medium, such as helium, is filled into the heat pump circulation system. That is, the compressor YQJ of the heat pump no longer extracts the hydrogen working medium in the second liquid storage tank, but uses the heat pump as an independent circulation system, and adopts the third circulating working medium, which can also achieve good results. The heat pump belongs to the prior art and will not be described in detail.

[0095] Preferably, the cylinder expander QG can be replaced by a turbine expander, or replaced by an expander of the prior art such as a screw expander or a centripetal expander.

[0096] Once hydrogen gas leaks, it will burn easily in the air. No matter what expander is used, the gas should be prevented from leaking.

[0097] Seawater and air are both huge sources of heat that are inexhaustible. The dual-fluid low-temperature cycle power system can meet the power needs of all ships and vessels, including large aircraft carriers. Its specific power is higher than that of power systems with existing technologies, which greatly simplifies the ship's power system and obtains zero-carbon, free power.

Claims

1. A power system for a space capsule, characterized in that: It consists of a high-temperature working fluid circulation system, a low-temperature working fluid circulation system, a set of heat pumps, an automatic controller and two cold boxes; among which: The high-temperature working medium circulation system is composed of at least one first liquid storage tank CYG1, a first liquid pump YB1, a jet pump SLB, a group of in-cabin heat exchangers NHRQ, a group of out-cabin heat exchangers WHRQ, and a group of countercurrent heat exchangers NLHRQ; wherein, the liquid working medium outlet of the first liquid storage tank CYG1 is connected in series to the inlet and outlet of the first liquid pump YB1, to the inlet and outlet of the jet pump SLB, to the inlet and outlet of the in-cabin heat exchanger HRQ and the out-cabin heat exchanger WHRQ after being connected in parallel, to the high-temperature channel inlet and outlet of the countercurrent heat exchanger NLHRQ, and to the inlet of the first liquid storage tank CYG1, and the air intake of the jet pump SLB is connected to the gas outlet of the first cold box LX1; The low-temperature working medium circulation system is composed of at least one second liquid storage tank CYG2, a second liquid pump YB2, a second heat exchanger HR2, a two-stroke cylinder expander QG for expansion work and compression exhaust and a connected generator; wherein the liquid working medium outlet of the second liquid storage tank CYG2, the inlet and outlet to the second liquid pump YB2, the inlet and outlet of the second heat exchanger HR2, the inlet and outlet to the low-temperature channel of the countercurrent heat exchanger NLHRQ, the inlet and outlet to the cylinder expander QG, and the inlet to the low-temperature liquid storage tank CYG2 are connected in series in sequence; the second heat exchanger HR2 is installed at the bottom of the first liquid storage tank CYG1. The boiling point temperature of the working fluid stored in the first liquid storage tank CYG1 needs to be higher than the boiling point temperature of the working fluid in the second liquid storage tank CYG2; Heat pump: It consists of a compressor YQJ, a first heat exchanger HR1 and a refrigeration expansion machine PZ; wherein, the air outlet of the second liquid storage tank CYG2, the inlet and outlet of the compressor YQJ, the inlet and outlet of the first heat exchanger HR1, the inlet and outlet of the refrigeration expansion machine PZ, and the inlet of the second liquid storage tank CYG2 are connected in series in sequence, and the compressor YQJ, the refrigeration expansion machine PZ and its driving motor operate coaxially; an exhaust port To LX is provided on the top of the first liquid storage tank CYG1, and the saturated air generated by the heat of the heat pump in the first liquid storage tank CYG1 is discharged from the exhaust port To LX on the top of the first liquid storage tank CYG1 to the second cold box LX2; the first heat exchanger HR1 is installed at the bottom of the first liquid storage tank CYG1; The countercurrent heat exchanger NLHRQ is installed in the first cold box LX1; the first liquid storage tank CYG1, the second liquid storage tank CYG2, the first liquid pump YB1, the second liquid pump YB2, the compressor YQJ, the refrigeration expander PZ and the cylinder expander QG are all installed in the second cold box LX2. The top of the second cold box LX2 is connected to the bottom of the first cold box LX1; Automatic controller KZQ is used to automatically control the temperature, pressure, flow and other parameters of each part of the system to maintain them at the set values.

2. A control method for a power system for a space capsule, the method being based on the power system for a space capsule according to claim 1, characterized in that: The specific steps include: The first liquid pump YB1 in the automatic control high-temperature working medium circulation system extracts a certain amount of liquid working medium from the first liquid storage tank CYG1 and sends it to the jet pump SLB. The jet pump SLB extracts a certain amount of gaseous working medium from the first cold box LX1, and sends the mixed working medium to the parallel circuit of the cabin heat exchanger NHRQ and the cabin heat exchanger WHRQ, where it is heated and vaporized to become normal-temperature working medium gas. The normal-temperature working medium gas then flows into the high-temperature channel of the countercurrent heat exchanger NLHRQ, transfers the heat to the low-temperature channel in the countercurrent heat exchanger NLHRQ, cools down in the high-temperature channel of the countercurrent heat exchanger NLHRQ, and liquefies and flows into the first liquid storage tank CYG1, completing the cycle. The second liquid pump YB2 of the automatic control low-temperature working medium circulation system extracts liquid working medium from the second liquid storage tank CYG2, sends it through the low-temperature channel of the second heat exchanger HR2 and the countercurrent heat exchanger NLHRQ to absorb heat and gasify into high-pressure steam, and the exhaust steam after expansion and work by the cylinder expander QG flows into the second liquid storage tank CYG2 to complete the cycle; The compressor YQJ of the automatic control heat pump extracts the working medium exhaust steam in the second liquid storage tank CYG2, compresses and heats it, and then flows through the first heat exchanger HR1 arranged in the first liquid storage tank CYG1, transfers the exhaust steam heat to the first liquid storage tank CYG1, and then liquefies and flows back to the second liquid storage tank CYG2 through the refrigeration expansion machine PZ; Automatic controller KZQ is used to control the pressure, temperature, flow and other parameters of each part of the system to run at the preset values.

3. A power system for a ship, characterized in that: The system is obtained by replacing the outboard heat exchanger WHRQ and the inboard heat exchanger NHRQ in the power system for the space capsule described in claim 1 with a cabin evaporator CQHQ with water as the intermediate medium of the heat source and an air heat exchanger KQHRQ with a hydrophobic coating on the surface.

4. The power system for a ship according to claim 3, characterized in that: The cabin vaporizer CQHQ is obtained by arranging a closed cabin at the bottom below the waterline of the hull, arranging a tubular heat exchanger at the top of the closed cabin, and injecting a low-boiling-point working medium into the closed cabin.

5. A control method for a power system of a ship, characterized in that: This method is based on the power system for a ship as described in claim 3 or 4, and in the control method of the power system for a space capsule as described in claim 2, the outboard heat exchanger WHRQ and the inboard heat exchanger NHRQ in the power system of the space capsule are replaced by a cabin evaporator CQHQ with water as the intermediate medium of the heat source and an air heat exchanger KQHRQ with a hydrophobic coating on the surface.

6. A power system for a space capsule, characterized in that: The system is a power system for a space capsule as described in claim 1, in which a group of heat absorption heat exchangers are connected in series between the air intake of the heat pump compressor YQJ and the outlet of the refrigeration expansion machine PZ and arranged on the top of the second liquid storage tank, and a third circulating working fluid is filled in the heat pump circulation system; and the connection between the compressor YQJ and the second liquid storage tank is disconnected.

7. A power system for a space capsule, characterized in that: The cylinder expander QG in the power system for a space capsule as described in claim 1 is replaced by a turbine expander, a screw expander or a centripetal expander.

Images