Combined cooling heating and power supply system based on pulse detonation

Abstract

The invention relates to the technical field of energy gradient utilization, and discloses a pulse detonation-based combined cooling heating and power supply system, which comprises a pulse detonation turbine engine used for performing acting compression on input external air and then mixing and combusting with injected fuel to generate fuel gas with first pressure; and the air compression equipment is used for carrying out secondary acting compression on the external air subjected to acting compression to generate compressed air with second pressure and inputting the compressed air into a bearing cavity, a turbine disc cavity and turbine blades in the pulse detonation turbine engine, and the second pressure is higher than the first pressure. Air with the pressure higher than that of fuel gas in the pulse detonation turbine engine is output through the air compression equipment, the pressure requirement can be met, an inner cavity of the pulse detonation turbine engine is sealed, meanwhile, the blades are cooled, and the situation that due to the fact that a traditional mechanical structure is additionally arranged, output power is reduced, and power consumption is reduced can be avoided. And the circulating heat efficiency and the heat-to-electricity conversion efficiency are effectively improved.

Description

Technical Field

[0001] The invention relates to the technical field of energy cascade utilization, and in particular to a pulse detonation-based combined heating, cooling and power system. Background Art

[0002] The combined heat and power system is an energy supply system based on the cascade utilization of energy, integrating heating, cooling and power generation processes. At present, the conventional combined heat and power system consists of a gas turbine / boiler, a generator, a refrigerant, a heat exchanger and a control system. Among them, the rotor parts in the gas turbine need to rely on bearings for limitation and rotation. The bearings have certain temperature limits when working. In order to prevent the bearings from failing due to high temperature, for gas turbines, part of the gas is usually introduced from the compressor outlet as a sealing gas to prevent the high-temperature gas from entering the bearing cavity. In addition, part of the compressor outlet airflow is introduced into the turbine blades to form a cooling air film, isolate the high-temperature gas, and prevent the turbine blades from ablation. However, the combustion mode of the gas turbine is based on isobaric combustion, and its cycle thermal efficiency is low, and the heat-to-electricity efficiency is difficult to be greatly improved.

[0003] In the prior art, under the condition of the same engine inlet parameters, the pulse detonation turbine engine based on isochoric combustion has higher cycle thermal efficiency and heat-to-electricity efficiency than the gas turbine based on isobaric combustion, which can effectively improve the power generation quality. However, there are a series of practical application problems in the use of pulse detonation turbine engines, such as the need to perform air sealing in the turbine disc cavity, bearing cavity and other cavities to prevent high-temperature combustion gas from entering the cavity and causing component failure; the air flow temperature can reach 800-900K after the compressor works and compresses, and the mixed combustion with fuel can further increase the air flow temperature by about 1000K. At this time, the turbine blades need to be cooled to prevent blade ablation, etc. Therefore, in gas turbines, it is often used to seal the cavity and cool the turbine blades by drawing out part of the compressor outlet air flow (the highest pressure point), while pulse detonation has a self-pressurization characteristic. At this time, the highest pressure point is the outlet of the detonation chamber, and sealing and cooling by drawing air from the compressor outlet cannot meet the pressure requirements. Summary of the invention

[0004] In view of this, the present invention provides a combined heat, cooling and power system based on pulse detonation to solve the problem that sealing and cooling cannot be achieved when a pulse detonation turbine engine is used.

[0005] The present invention provides a combined cooling, heating and power system based on pulse detonation, the system comprising:

[0006] The pulse detonation turbine engine is used to compress the input external air, and mix and burn the compressed external air with the injected fuel to generate combustion gas of a first pressure;

[0007] The air compression equipment is connected to the pulse detonation turbine engine, and is used to perform secondary work compression on the external air after work compression to generate compressed air of a second pressure, and input the compressed air into the bearing cavity, turbine disc cavity and turbine blades in the pulse detonation turbine engine, and the second pressure is higher than the first pressure.

[0008] The pulse detonation-based combined heat and power system provided by the embodiment of the present invention performs work compression on the input external air through the pulse detonation turbine engine, and mixes and burns the compressed external air and the injected fuel to generate combustion gas of a first pressure, and at the same time, the air compression device performs secondary work compression on the compressed external air to generate compressed air of a second pressure, and inputs the compressed air into the bearing cavity, turbine disc cavity and turbine blades in the pulse detonation turbine engine. The present invention outputs air with a pressure higher than the combustion gas pressure in the pulse detonation turbine engine through the air compression device, which can meet the pressure requirements, seal the inner cavity of the pulse detonation turbine engine, and cool the blades at the same time, which can avoid the reduction of output power due to the addition of traditional mechanical structure, and effectively improve the cycle thermal efficiency and heat-to-electricity efficiency.

[0009] In an optional embodiment, a pulse detonation turbine engine includes: an air inlet for inputting outside air; a compressor for compressing the outside air to perform work; a pulse detonation combustion chamber for mixing and burning the compressed outside air and injected fuel to generate combustion gas of a first pressure and a first temperature; a gas turbine for converting the internal energy of the combustion gas into a first kinetic energy and driving the compressor based on the first kinetic energy; a power turbine for converting the internal energy of the combustion gas into a second kinetic energy; and an exhaust device for outputting the combustion gas based on a gas separation structure.

[0010] The present invention uses a pulse detonation turbine engine to provide power, heat and cooling, and can provide higher cycle thermal efficiency and heat-to-electricity efficiency, meet the user's usage needs, and thus improve user satisfaction.

[0011] In an optional embodiment, the system also includes: a generator connected to the power turbine for converting the second kinetic energy into electrical energy; a heating device connected to the exhaust device for gas-based heating; and a refrigeration device connected to the exhaust device for gas-based refrigeration.

[0012] The present invention can provide a combined heating, cooling and power generation system integrating heating, cooling and power generation by arranging a generator, a heating device and a cooling device to meet the cooling, heating and power supply needs of users at different times.

[0013] In an optional embodiment, the air inlet of the air compression equipment is connected to the air outlet of the compressor, and a water-cooled heat exchanger is provided between the air inlet of the air compression equipment and the air outlet of the compressor, the water-cooled heat exchanger is used to exchange heat between the outside air after work compression and the input tap water, so as to generate domestic hot water of the second temperature; the air outlet of the air compression equipment is respectively connected to the bearing cavity, the turbine disc cavity and the turbine blades based on the air separation structure, so as to seal the bearing cavity and the turbine disc cavity based on the compressed air, and cool the turbine blades based on the compressed air.

[0014] The present invention uses a water-cooled heat exchanger to cool the outside air in the pulse detonation turbine engine whose temperature and pressure are increased after being compressed by work. On the one hand, it can generate domestic hot water through heat exchange to meet the water needs of users and improve energy utilization. On the other hand, it can seal the cavity and cool the turbine blades based on the cooled compressed air to meet the pressure requirements of the pulse detonation turbine engine.

[0015] In an optional embodiment, the input end of the generator is connected to the power turbine via a reducer, which is used to reduce the first speed of the power turbine to a second speed; the output end of the generator is connected to an air compression device, a heating device, a refrigeration device and / or an external electrical device to provide electrical energy.

[0016] The present invention connects the generator and the power turbine of the pulse detonation turbine engine through a reducer, and can match the shaft speeds of the engine and the generator, thereby realizing the conversion of the mechanical energy of the generator into electrical energy based on the kinetic energy of the engine, thereby meeting the electricity demand of the user and the electricity demand of the electrical equipment in the combined heat and power system.

[0017] In an optional embodiment, if the pulse detonation turbine engine is configured as a turboshaft engine or a turboprop engine, a power output shaft is provided in the pulse detonation turbine engine, and a generator is driven based on the power output shaft; if the pulse detonation turbine engine is configured as a turbofan engine or a turbojet engine, a turbine is provided in the pulse detonation turbine engine, and a generator is driven based on the turbine.

[0018] The present invention can expand the applicability of the combined heating, cooling and power generation system by arranging adaptive kinetic energy transmission equipment between different types of engines and generators, and can realize the conversion of mechanical energy into electrical energy in different product models.

[0019] In some optional embodiments, a one-way valve is provided at the front end of the pulse detonation combustion chamber to prevent the pressure in the pulse detonation combustion chamber from being transmitted back.

[0020] The present invention sets a one-way valve in the pulse detonation combustion chamber, which can prevent the pressure from transmitting back upstream when the detonation wave propagates to both ends, and at the same time, the detonation wave propagating downstream is discharged to the turbine. That is, after the pulse detonation combustion chamber discharges the combustion gas, the generated expansion wave propagates upstream of the pulse detonation combustion chamber, and the pressure at the head of the pulse detonation combustion chamber gradually decreases until the compressor outlet airflow can flow smoothly into the detonation chamber, and the pulse detonation combustion chamber starts the next cycle.

[0021] In an alternative embodiment, the fuel is petroleum waste gas or biomass energy.

[0022] The present invention uses petroleum waste gas or biomass energy as fuel, and can improve resource utilization and reduce pollution in scenarios such as animal husbandry, planting or oil extraction.

[0023] In an optional embodiment, the compressor is an axial compressor, a centrifugal compressor or a combined compressor.

[0024] The present invention can provide air of a certain temperature and pressure to the pulse detonation combustion chamber through different types of compressors, thereby atomizing and mixing with the ejected fuel to form a combustible mixture, forming a detonation wave after ignition, and driving the turbine rotor to generate kinetic energy.

[0025] In an optional embodiment, the air inlet of the air compression device is connected to the outside atmosphere.

[0026] The present invention directly uses the external atmosphere as the air intake input of the air compression equipment, which can improve the applicability of the air compression equipment and achieve sealing and cooling of the pulse detonation combustion chamber in different scenarios.

[0027] The embodiment of the present invention mainly solves the technical problem of low cycle thermal efficiency and heat-to-electricity efficiency when using conventional gas turbines as output power equipment of the combined heat and power system, and can be matched and applied to large-scale animal husbandry and planting industries, while meeting the power generation, heating and refrigeration needs of users. The embodiment of the present invention can make full use of biomass energy (such as biogas, etc.) or petroleum waste gas generated by the above industries, reducing the waste gas treatment cost, and at the same time provides a technical solution for solving the pulse detonation turbine engine bleed air sealing and turbine cooling. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0029] Figure 1 is a structural block diagram of a conventional combined cooling, heating and power system according to an embodiment of the present invention;

[0030] Figure 2 is a structural block diagram of a combined cooling, heating and power system based on pulse detonation according to an embodiment of the present invention;

[0031] Figure 3 is a structural schematic diagram of a combined cooling, heating and power system based on pulse detonation according to an embodiment of the present invention;

[0032] Figure 4 is a schematic diagram of a specific structure of a combined cooling, heating and power system based on pulse detonation according to an embodiment of the present invention;

[0033] Figure 5 is a schematic diagram of the main flow channel and fuel supply position of a pulse detonation-based combined heat and power system according to an embodiment of the present invention;

[0034] Figure 6 The pulse detonation turbine engine and the air flow pressure change in the air compressor of the pulse detonation combined heat and power system according to an embodiment of the present invention;

[0035] Figure 7 It is a schematic diagram of the details of the high-pressure air flow path at the outlet of the air compressor of the pulse detonation-based combined heat and power system according to an embodiment of the present invention.

[0036] Explanation of the reference numerals: 100 - pulse detonation turbine engine; 101 - air inlet; 102 - compressor; 103 - pulse detonation combustion chamber; 104 - gas turbine; 105 - power turbine; 106 - exhaust device; 107 - power output shaft; 200 - air compression equipment; 300 - generator; 400 - heating equipment; 500 - refrigeration equipment; 600 - reducer; 700 - water-cooled heat exchanger. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0038] The embodiments of the present invention are applicable to application scenarios where electric energy, heat energy and refrigeration are required to be provided simultaneously in industries such as animal husbandry, planting or oil extraction. Figure 1As shown, it consists of a gas turbine / boiler, a generator, a refrigerant, a heat exchanger, and a control system. Among them, the working principle of the gas turbine is: the outside air is compressed by the compressor, the gas pressure and temperature increase, and after flowing into the combustion chamber, it is mixed with the injected fuel and burned, and the high-temperature and high-pressure gas formed hits the turbine, driving the turbine to drive the compressor and the externally connected generator to rotate at high speed, and then output electrical work. The working principle of the refrigerator is (taking the lithium bromide absorption refrigerator as an example): using the waste heat of the tail gas as the working heat source, when the lithium bromide aqueous solution is heated in the generator, the water in the solution is continuously vaporized, and then the solubility of the lithium bromide aqueous solution in the generator is continuously increased, and then enters the absorber; after the water vapor enters the condenser, it is cooled by the cooling water in the condenser and condensed to become high-pressure and low-temperature liquid water; when the water in the condenser enters the evaporator through the throttle valve, it rapidly expands and vaporizes, and absorbs a large amount of heat from the refrigerant water in the evaporator during the vaporization process, thereby achieving the purpose of cooling and refrigeration. The working principle of the heat exchanger is: using the waste heat of exhaust gas as the working heat source (heat source fluid), the heat source and cold source fluids flow in the pipes inside the heat exchanger and exchange heat on the pipe walls to provide the required heat load.

[0039] At present, most combined heat and power systems are proposed for regional or large-scale building complexes. When the combined heat and power systems are applied in industries such as animal husbandry (animal breeding) and planting (greenhouse vegetables), the degree of automation can be improved to meet the demand for heat, power and cooling in different periods. At the same time, biomass energy (biogas, etc.) can be used as fuel to reuse energy, greatly improve energy utilization and reduce pollution. In addition, existing combined heat and power systems often use gas turbines, and the combustion mode of gas turbines is based on isobaric combustion. The efficiency of its components and cycle thermal efficiency have basically reached the limit, and the performance is difficult to significantly improve. Therefore, the cycle thermal efficiency is low, and the heat-to-electricity efficiency is difficult to significantly improve, which easily leads to waste of resources.

[0040] After replacing the pulse detonation turbine engine based on isochoric combustion, the cycle thermal efficiency can be improved, but the highest pressure point is at the combustion chamber outlet. At this time, the sealing and cooling of the bleed air from the compressor outlet cannot meet the pressure requirements, so it is necessary to solve the problems of bleed air sealing and turbine cooling. If conventional mechanical devices (axial flow, centrifugal compressors, etc.) are used to pressurize the compressor outlet airflow, the efficiency is not high and the compression ratio is difficult to meet the requirements. In addition, part of the power needs to be provided to drive the mechanical device to achieve the supercharging effect, which will affect the heat-to-electricity efficiency.

[0041] Therefore, an embodiment of the present invention provides a pulse detonation-based combined heat and power system, which seals and cools the pulse detonation turbine engine through air compression equipment to achieve the effect of improving the cycle thermal efficiency and heat-to-electricity efficiency.

[0042] According to an embodiment of the present invention, a pulse detonation-based combined heat and power system embodiment is provided. It should be noted that, as used below, the term "module" can implement a combination of software and / or hardware with a predetermined function. Although the device described in the following embodiments is preferably implemented in software, the implementation of hardware, or a combination of software and hardware, is also possible and conceivable.

[0043] In this embodiment, a combined cooling, heating and power system based on pulse detonation is provided. Figure 2 is a structural block diagram of a combined cooling, heating and power system based on pulse detonation according to an embodiment of the present invention, such as Figure 2 As shown, the system includes: a pulse detonation turbine engine 100, which is used to perform work compression on the input external air, and mix and burn the compressed external air with the injected fuel to generate combustion gas of a first pressure; an air compression device 200, which is connected to the pulse detonation turbine engine 100, and is used to perform secondary work compression on the compressed external air to generate compressed air of a second pressure, and input the compressed air into the bearing cavity, turbine disc cavity and turbine blades in the pulse detonation turbine engine 100, and the second pressure is higher than the first pressure.

[0044] Specifically, in the embodiment of the present invention, Figure 2 As shown, the combined heat, cooling and power system also includes: a generator 300, connected to the pulse detonation turbine engine 100, for converting kinetic energy into electrical energy; a heating device 400, connected to the pulse detonation turbine engine 100, for heating based on gas; and a refrigeration device 500, connected to the pulse detonation turbine engine 100, for refrigeration based on gas. The embodiment of the present invention can provide a combined heat, cooling and power system integrating heating, cooling and power generation, so as to meet the user's demand for heat, cooling and power supply at different times and improve user satisfaction. Among them, the pulse detonation turbine engine 100 is a new concept engine that uses high-temperature and high-pressure fuel gas generated by pulsed detonation waves to generate thrust. It directly uses the detonation waves generated by detonation combustion in the combustion chamber to compress the gas and then generate power. The detonation waves generated by detonation combustion rapidly increase the pressure and temperature of the fuel gas (the pressure can reach 100 atmospheres and the temperature can reach 2000°C). Therefore, it has the advantages of high thermal cycle efficiency and simple structure. Figure 3 As shown, taking animal husbandry, planting or oil extraction as an example, the fuel provided to the pulse detonation turbine engine 100 is biomass energy (for example, biogas generated by animal breeding grounds, fuel generated by decaying materials such as greenhouse vegetable straw) or petroleum waste gas, which can improve resource utilization and reduce pollution. Figure 4As shown, the heating device 400 adopts an exhaust gas waste heat exchanger, and the cooling device 500 adopts a lithium bromide absorption refrigerator, and its working principle is the same as the working principle of related equipment in a conventional combined heat and power system, and can also be replaced by other heating and cooling equipment, such as an evaporator, etc., which will not be repeated here.

[0045] In some optional embodiments, such as Figure 4As shown, the pulse detonation turbine engine 100 of the embodiment of the present invention comprises: an air inlet 101 for inputting outside air; a compressor 102 for compressing the outside air, which can be set as an axial compressor, a centrifugal compressor or a combined compressor in other forms; a pulse detonation combustion chamber 103 for mixing and burning the outside air after the work compression and the injected fuel to generate a combustion gas of a first pressure and a first temperature, wherein the pulse detonation combustion chamber 103 is a multi-tube pulse detonation combustion chamber, which is used to ensure the successful detonation before Under the premise, the configuration of the multi-tube pulse detonation combustion chamber and the type of obstacles in the detonation chamber are not restricted, and can also be replaced by other components based on isochoric combustion, such as wave rotors; gas turbine 104, used to convert the internal energy of the gas into the first kinetic energy, and drive the compressor 102 based on the first kinetic energy; power turbine 105, used to convert the internal energy of the gas into the second kinetic energy, and drive the generator 300 based on the second kinetic energy; exhaust device 106, used to output the gas to the heating equipment 400, the refrigeration equipment 500 and the outside atmosphere based on the gas separation structure. Among them, the working principle of the pulse detonation turbine engine 100 is: the outside air flows through the inlet 101, is compressed by the compressor 102, the air flow pressure and temperature increase, and then flows into the multi-tube pulse detonation combustion chamber 103, mixed with the injected fuel and ignited and burned. In the combustion chamber, the mixing ratio of fuel and air is very important. When the fuel and air are filled into the combustion chamber in an appropriate ratio, efficient detonation combustion can be achieved. When the fuel and air are introduced into the combustion chamber, there are two detonation modes: direct detonation and indirect detonation. In direct detonation, the ignition device triggers a violent chemical reaction, which instantly releases huge energy and forms a strong detonation wave; indirect detonation is that the ignition device ignites the combustible mixture in the combustion chamber and generates a series of compression waves, which then develop into shock waves. The shock waves heat and compress the unreacted mixture, produce an explosion center, and form a strong shock wave, which couples with the reaction zone to form an overdriven detonation, and finally establishes a stable detonation wave as the wave speed decreases. Since the detonation combustion process is extremely short (millisecond level) and the propagation speed is fast (about 2000m / s), the pressure in the combustion chamber is difficult to reach equilibrium in a short time. It is generally believed that detonation combustion is similar to isochoric combustion, so it can significantly improve the thermal cycle efficiency. The high-temperature and high-pressure combustion gas formed impacts the gas turbine 104 and the power turbine 105 after passing through the combustion chamber, and converts the internal energy of the combustion gas into kinetic energy after passing through the turbine. The power generated by the kinetic energy of the gas turbine 104 is used to drive the compressor 102 again, and the power generated by the kinetic energy of the power turbine 105 is used to drive the generator 300 and other accessory devices. Then the gas is discharged into the heating equipment 400, the refrigeration equipment 500 and the outside atmosphere through the exhaust device 106 with a gas separation structure.

[0046] In some optional embodiments, such as Figure 4As shown, if the pulse detonation turbine engine 100 of the embodiment of the present invention is set as a turboshaft engine or a turboprop engine, a power output shaft 107 is provided in the pulse detonation turbine engine 100, and the power output shaft 107 outputs power to drive the generator 300 to work, because the turboshaft engine or turboprop engine drives the rotor or propeller and accessory devices (including generators, etc.) through the power turbine shaft, and its working process includes: air compression, combustion, energy conversion and output power, which will not be repeated here. Furthermore, because the rotor speed of the engine is as high as tens of thousands of revolutions per minute, and conventional generators do not require such a high speed, a reducer 600 is required to match the speed of the engine and the generator, so as to realize the conversion of the mechanical energy of the generator into electrical energy based on the kinetic energy of the engine. In the embodiment of the present invention, the input end of the generator 300 is connected to the power output shaft 107 connected to the power turbine 105 through a reducer 600, and the output end of the generator 300 is connected to the air compression equipment 200, the heating equipment 400, the refrigeration equipment 500 and / or the external electrical equipment, which is used to provide the electrical load required by each electrical equipment to meet the power demand of the electrical equipment in the combined heat and power system, or the air compression equipment 200, the heating equipment 400, and the refrigeration equipment 500 can also be powered by an external power supply to expand the application scenario, which is not limited here. In summary, the embodiment of the present invention adopts a dual-rotor structure, the gas turbine 104 and the compressor 102 form a gas generator rotor, and the power turbine 105, the power output shaft 107 and the accessory device form a rotor. Furthermore, the engine can also be derived into a three-rotor structure and other forms, which are not limited here.

[0047] In some optional embodiments, if the pulse detonation turbine engine 100 of the embodiment of the present invention is set as a turbofan engine or a turbojet engine, a turbine is provided in the pulse detonation turbine engine 100, and a generator is driven based on the turbine, that is, the thermal energy in the high-temperature and high-pressure gas is converted into mechanical energy through the turbine, and connected to the generator 300 for power output, thereby driving the generator 300 to work. The present invention can expand the applicability of the combined heat and power system by providing an adaptive kinetic energy transmission device between different types of engines and generators, and can realize the conversion of mechanical energy to electrical energy in different product models. The specific model selection is determined by the user according to actual needs and is not limited here.

[0048] In some optional embodiments, such as Figure 5As shown, the air in the pulse detonation combustion chamber 103 compressed by the compressor 102 flows into the pulse detonation combustion chamber 103, is atomized and mixed with the fuel sprayed from the fuel supply position to form a combustible mixture, and then ignites and burns. Under the continuous superposition of shock waves, a detonation wave is formed at a certain position of the pulse detonation combustion chamber 103, and the detonation wave propagates to both ends. Therefore, a one-way valve (which can be a pneumatic valve / mechanical valve) is provided at the head of the pulse detonation combustion chamber 103 to prevent the detonation chamber pressure from transmitting back upstream, and the detonation wave propagating downstream is discharged to the turbine, that is, after the pulse detonation combustion chamber 103 discharges the combustion gas, the generated expansion wave propagates upstream of the pulse detonation combustion chamber 103, and the pressure at the head of the pulse detonation combustion chamber 103 gradually decreases, and the pulse detonation combustion chamber 103 is in a low-pressure state until the airflow at the outlet of the compressor 102 can smoothly flow into the pulse detonation combustion chamber 103, at which time the pulse detonation combustion chamber 103 starts the next cycle.

[0049] In some optional embodiments, the air flow formed in the pulse detonation combustion chamber 103 is as follows: Figure 5 As shown by the middle arrow, in order to prevent the high-temperature airflow in the main channel from entering the turbine disc cavity, bearing cavity and other cavities formed inside the pulse detonation turbine engine 100, the embodiment of the present invention uses the gas compressed by the air compression device 200 to seal the cavity, and at the same time can cool the turbine blades. The air compression device 200 can be set as an air compressor, or other equipment or mechanical structure that can compress air. Taking the air compressor as an example, part of the air compressed by the compressor 102 flows into the pulse detonation combustion chamber 103 to participate in combustion, and part of it flows into the water-cooled heat exchanger 700 to exchange heat with the input tap water to produce domestic hot water, meet the user's water demand, and improve energy utilization. The temperature of the air after heat exchange is reduced, and it flows into the air compressor along the pipeline. The air is pressurized by the air compressor to make the outlet air pressure higher than the gas pressure at the outlet of the pulse detonation combustion chamber 103 (here is the highest pressure point of the pulse detonation turbine engine 100), meeting the pressure requirements of the pulse detonation turbine engine. The air pressure changes in the air compressor and the pulse detonation turbine engine 100 are shown as follows. Figure 6As shown, it can be seen that the gas pressure at the outlet of the pulse detonation combustion chamber 103 is the highest in the axial position of the entire pulse detonation turbine engine, and the air pressure at other positions is relatively low, while the air pressure at the outlet point of the air compressor is higher than the gas pressure at the outlet of the pulse detonation combustion chamber 103, so the cavity can be sealed. At the same time, an air separation structure is provided at the outlet of the air compressor to divide the formed outlet high-pressure air into two parts, one part is introduced into the bearing cavity, etc. to seal the cavity, and the other part is introduced into the turbine blades, which can form a cooling air film on the surface of the blades, thereby isolating the high-temperature gas and cooling the blades. The embodiment of the present invention can simultaneously solve the problems of bleed air sealing and blade cooling of the pulse detonation turbine engine 100. The flow direction of the high-pressure air at the outlet of the air compressor is shown in the figure. Figure 7 As shown, they include: the flow trajectory of the high-pressure air at the air compressor outlet in the turbine blades and the turbine disc cavity, the trajectory of the high-pressure air at the air compressor outlet ejected from the inside of the turbine blades, and the flow trajectory of the high-temperature and high-pressure combustion gas formed by combustion in the pulse detonation combustion chamber 103.

[0050] In some optional implementations, if the water-cooled heat exchanger 700 is not provided, the embodiment of the present invention can directly connect the air inlet of the air compressor to the outside atmosphere, compress the input outside air to do work, and use the compressed gas to seal the cavity. Since the temperature of the compressed air is lower than the temperature of the gas in the detonation combustion chamber, it can be introduced into the turbine blades to cool the turbine blades, thereby expanding the application scenarios of the system.

[0051] In some optional embodiments, such as Figure 4As shown, an air inlet is provided at the exhaust device 106 of the pulse detonation turbine engine 100 in the embodiment of the present invention, and part of the high-temperature and high-pressure gas is introduced into the exhaust gas waste heat exchanger and the refrigerator through the gas separation structure, respectively, to serve as the working heat source of the two devices. Among them, the working principle of the exhaust gas waste heat exchanger is mainly based on the heat exchange principle, and heat is exchanged through the temperature difference between different gases. Specifically, the high-temperature gas is used as the working heat source of the heat exchange process. When the high-temperature gas passes through the hot side channel of the heat exchanger, the heat it carries is transferred to the cooling medium (such as water, air or other fluids) located in the cold side channel through the wall of the heat exchanger. In this process, the high-temperature gas is cooled, and the cooling medium is heated, realizing the transfer and recovery of heat. There are many types of exhaust gas waste heat exchangers, including fin tube heat exchangers, plate fin heat exchangers, and spiral tube heat exchangers, which are not limited here. The refrigerator realizes the transfer and transfer of heat by circulating the working fluid (refrigerant), thereby achieving the cooling effect. The process includes: compression process, condensation process, expansion process and evaporation process, etc. The high-temperature and high-pressure gas is used as the working heat source of the evaporation process. The heating and cooling can meet the heating or cooling needs of users at different times, and the remaining high-temperature and high-pressure gas flows into the outside atmosphere through the exhaust device 106.

[0052] The pulse detonation-based combined heat and power system provided in the embodiment of the present invention performs work compression on the input external air through the pulse detonation turbine engine, and mixes and burns the compressed external air and the injected fuel to generate a first pressure of gas, and at the same time, the air compression device performs a second work compression on the compressed external air to generate a second pressure of compressed air, and the compressed air is input into the bearing cavity, turbine disc cavity and turbine blades in the pulse detonation turbine engine, wherein the first pressure and the second pressure are set according to the specific operation conditions of the combined heat and power system, and the second pressure is higher than the first pressure, which is not limited here. The present invention outputs air with a pressure higher than the gas pressure in the pulse detonation turbine engine through the air compression device, which can meet the pressure requirements, seal the inner cavity of the pulse detonation turbine engine, and cool the blades at the same time, which can avoid the reduction of output power due to the addition of traditional mechanical structure, and effectively improve the cycle thermal efficiency and heat-to-electricity efficiency. In addition, using petroleum waste gas or biomass energy as fuel can reduce the cost of treating waste gas such as petroleum, significantly improve energy utilization, and reduce pollution.

[0053] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A combined cooling, heating and power system based on pulse detonation, characterized in that: The system comprises: The pulse detonation turbine engine is used to compress the input external air, and mix and burn the compressed external air with the injected fuel to generate combustion gas of a first pressure; An air compression device is connected to the pulse detonation turbine engine, and is used to perform secondary work compression on the external air after work compression to generate compressed air of a second pressure, and input the compressed air into the bearing cavity, turbine disc cavity and turbine blades in the pulse detonation turbine engine, wherein the second pressure is higher than the first pressure.

2. The system according to claim 1, characterized in that The pulse detonation turbine engine comprises: An air inlet, used for inputting the outside air; A compressor, used for compressing the external air; The pulse detonation combustion chamber is used to mix and burn the external air compressed by work and the injected fuel to generate combustion gas of a first pressure and a first temperature; a gas turbine, configured to convert the internal energy of the gas into first kinetic energy, and drive the compressor based on the first kinetic energy; A power turbine, used for converting the internal energy of the combustion gas into a second kinetic energy; An exhaust device is used to output the gas based on the gas distribution structure.

3. The system according to claim 2, characterized in that Also includes: a generator connected to the power turbine and configured to convert the second kinetic energy into electrical energy; A heating device, connected to the exhaust device, for providing heat based on the gas; A refrigeration device is connected to the exhaust device and is used for refrigeration based on the gas.

4. The system according to claim 2, characterized in that The air inlet of the air compression device is connected to the air outlet of the compressor, and a water-cooled heat exchanger is provided between the air inlet of the air compression device and the air outlet of the compressor, and the water-cooled heat exchanger is used to exchange heat between the outside air compressed by work and the input tap water to generate domestic hot water of the second temperature; The air outlet of the air compression device is connected to the bearing cavity, the turbine disc cavity and the turbine blades respectively based on the air distribution structure, so as to seal the bearing cavity and the turbine disc cavity based on the compressed air, and cool the turbine blades based on the compressed air.

5. The system according to claim 3, characterized in that The input end of the generator is connected to the power turbine via a reducer, and the reducer is used to reduce the first speed of the power turbine to a second speed; The output end of the generator is connected to the air compression equipment, the heating equipment, the refrigeration equipment and / or external electrical equipment for providing electrical energy.

6. The system according to claim 3, characterized in that If the pulse detonation turbine engine is configured as a turboshaft engine or a turboprop engine, a power output shaft is provided in the pulse detonation turbine engine, and the generator is driven based on the power output shaft; If the pulse detonation turbine engine is configured as a turbofan engine or a turbojet engine, a turbine is provided in the pulse detonation turbine engine, and the generator is driven based on the turbine.

7. The system according to claim 2, characterized in that A one-way valve is arranged at the front end of the pulse detonation combustion chamber to prevent the pressure in the pulse detonation combustion chamber from being transmitted back.

8. The system according to claim 1, characterized in that The fuel is petroleum waste gas or biomass energy.

9. The system according to claim 2, characterized in that The compressor is an axial flow compressor, a centrifugal compressor or a combined compressor.

10. The system according to claim 4, characterized in that The air inlet of the air compression device is connected to the outside atmosphere.

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