12results about How to "Lower pressure ratio" patented technology

The invention discloses a refrigerating system for providing cooling capacity in a liquid nitrogen temperature zone. The refrigerating system comprises a compressor, a pre-cooling unit, a throttling valve and a cold end heat exchanger which are sequentially connected to form a liquid nitrogen throttling refrigerating unit. The pre-cooling unit comprises a first-stage pre-cooling heat exchanger and a second-stage pre-cooling heat exchanger which are arranged in series, the cooling capacity of the first-stage pre-cooling heat exchanger is provided by a refrigeration unit capable of providing the refrigeration temperature of 265-285K, and the cooling capacity of the second-stage pre-cooling heat exchanger is provided by a refrigeration unit capable of providing the refrigeration temperature of 190-220K. Compared with the traditional non-precooling working condition, the precooling at the inlet of the heat exchanger has the advantages that the high pressure is obviously reduced, the pressure ratio is small, and the cooling capacity is sufficient. The advantage is particularly obvious when the pre-cooling temperature is low. And a two-stage refrigeration mode is adopted, accurate control over the cooling capacity can be achieved, and the energy consumption of the system is reduced while it is guaranteed that the cooling capacity is sufficient. In addition, photovoltaic power is used for providing electric energy, the ice storage tank is adopted, and energy conservation and consumption reduction in the refrigeration process can be achieved through the electricity price peak-valley price difference.

The invention provides a hydrocarbon fuel cell aero-engine, a gas compressor and a fan in the engine are driven by a motor and can also be driven by a turbine shaft, a fuel cell system is located behind a turbine, and a partial oxidation reforming reactor, a combustion chamber, a fuel delivery pump and an exhaust nozzle are sequentially connected. Tail gas of the fuel cell system and gas which does not react completely are used for driving the turbine to rotate, the main shaft is driven to drive the gas compressor and the fan to work, electric energy generated by electrochemical reaction in the fuel cell system can also be used for driving the generator to work, and two working modes of driving the gas compressor and the fan are adopted; the problem of poor economical efficiency caused by the fact that a turbine is used for driving the gas compressor in the high altitude is solved; through the working modes of the dual-drive air compressor and the fan, the engine can be freely switched between the high altitude and the low altitude according to requirements in the using process. The advantages of cleanness and high efficiency of the fuel cell are utilized, and the problem that a traditional aero-engine is high in oil consumption rate is solved.

The invention provides a dual-temperature refrigerating system, an air conditioning unit and a defrosting control method. The dual-temperature refrigerating system comprises a first compressor and a condenser; the low-temperature loop is provided with a low-temperature evaporator, and the low-temperature evaporator communicates with the first compressor and the condenser; the medium-temperature loop comprises an evaporator branch and a medium-temperature evaporator arranged on the evaporator branch; the medium-temperature evaporator comprises a first evaporator and a second evaporator which are connected in series, and the first evaporator and the second evaporator are arranged on the evaporator branch at an interval; and the controller is used for converting the refrigerant circulation direction between the first evaporator and the second evaporator according to the frosting condition of the first evaporator or the second evaporator so as to defrost the first evaporator or the second evaporator. According to the double-temperature refrigerating system, the technical problems that in the related technology, the cost is increased and the practicability is poor due to the fact that two independent refrigerating systems are adopted in a double-temperature-zone system are solved.

The present invention relates to the technical field of refrigeration cycle, and specifically to a refrigeration system and circulation method for realizing low-temperature refrigeration, wherein the refrigeration system comprises a high-temperature cycle system and a low-temperature cycle system, wherein the high-temperature cycle system comprises a high-temperature low-pressure compressor, a high-temperature high-pressure compressor, a high-temperature condenser, a high-temperature intermediate cooler, a high-temperature low-pressure economizer and a condensing evaporator connected in series in sequence, wherein the high-temperature intermediate cooler is connected to the pipeline between the high-temperature low-pressure compressor and the high-temperature high-pressure compressor through a pipeline, and the high-temperature low-pressure economizer is connected to the high-temperature low-pressure compressor through a pipeline; and the low-temperature cycle system comprises an evaporator, a regenerator, a low-temperature low-pressure compressor, a low-temperature high-pressure compressor, a condensing evaporator and a liquid storage device connected in series, wherein the outlet of the liquid storage device is connected to the regenerator, and the regenerator is connected to the evaporator through a pipeline, so that the refrigerant circulates and refrigerates in a subcritical state, thereby improving the refrigeration efficiency.

The invention discloses an environment regulation and control device and method suitable for an intelligent control cabinet of a transformer substation. The environment regulation and control device comprises a controller, a sensing module, a gas transmission tail end regulation and control module, an auxiliary module and a gas source module. The sensing module comprises a temperature and humidity sensor arranged in the intelligent control cabinet; the air source module comprises a precooler, an air inlet buffer device, a compressor, an aftercooler and a drying pressure stabilizing device which are connected in sequence; the gas transmission tail end regulation and control module comprises a regulation valve group and an expansion machine; the auxiliary module comprises auxiliary compressors, and each auxiliary compressor and one expansion machine are coaxially arranged. According to the environment regulation and control device and method suitable for the intelligent control cabinet of the transformer substation, the centralized and reasonable environment regulation and control device is designed for a large number of outdoor intelligent control cabinets in the transformer substation, and the intelligent control cabinet of the transformer substation can be safer and more reliable in combination with a specific regulation and control method; and the intelligent control process of the intelligent control cabinet of the transformer substation is promoted.

The heat pump electricity storage system comprises a heat pump loop, a high-temperature heat storage module, a low-temperature cold storage module and an electricity generation module, and the heat pump loop comprises a first compressor, a second compressor, a heat pump regenerator, a first heat exchanger, a heat pump recooler and a second heat exchanger; the first compressor, the cold side of the heat pump regenerator, the second compressor, the first heat exchanger, the hot side of the heat pump regenerator, the fourth heat exchanger, the hot side of the heat pump recooler, the first expansion machine, the second heat exchanger and the cold side of the heat pump recooler are sequentially connected through pipelines to form a loop, and the first heat exchanger is used for exchanging heat with the high-temperature heat storage module. The second heat exchanger is used for exchanging heat with the low-temperature cold storage module; according to the heat pump heat regenerator and the heat pump cold regenerator, waste heat and waste cold generated after heat exchange of a working medium and a heat storage / cold medium can be recycled correspondingly, through the two-stage compression intermediate heating and heat regeneration and cold regeneration design, the pressure ratio and the temperature ratio are reduced, the development difficulty of thermal machinery is lowered, and meanwhile the electricity-heat conversion performance of the heat pump is improved.

The invention discloses a self-oil-return ejector synergistic refrigerator system which comprises a compressor, a condenser, a drying filter, an oil return pipe set, an ejector, a gas-liquid separator, a throttling device, an evaporator, an oil return bend and a one-way valve. A high-pressure working medium after condensation and heat regeneration ejects a low-pressure working medium of the evaporator in the ejector, gas-liquid separation is performed after mixing and diffusion, intermediate pressure gas enters the compressor, the pressure ratio and power consumption are reduced, saturated liquid enters the evaporator for heat exchange after being throttled by the throttling device, the unit refrigerating capacity is improved, and meanwhile the system performance is improved through heat regeneration of an air return pipe and an outlet of the condenser. The one-way valve is connected with the evaporator and the compressor inlet, low pressure is formed at the compressor inlet during starting, the one-way valve is opened, lubricating oil accumulated in the evaporator returns to the compressor, and oil return difficulty caused by a gas-liquid separator is solved. By means of the time difference established by pressure at different positions when the system is started, the oil return difficulty is solved, the operation reliability is improved, and the novel refrigerator system is simple and efficient.

The invention relates to a complete machine performance calculation method of a pulse detonation turbofan engine, which comprises the following steps of: performing design point performance calculation according to an air inlet channel, a fan component, an air compressor component, a mixing chamber and an exhaust nozzle of the pulse detonation turbofan engine; according to the method, performance calculation is sequentially carried out on a gas compressor component, a pulse detonation combustion chamber and a turbine component in the inner duct and the outer duct, obtained outlet parameters of the inner duct and the outer duct are compared with an iterative fan pressure ratio for judgment till static pressure balance of the inner duct and the outer duct is achieved, and finally performance parameters of the engine are obtained. The engine thrust is FN, the engine unit thrust is FS, and the engine unit oil consumption rate is SFC. When the method is used for overall design of the aero-engine, the pressure ratio of compression parts of the pulse detonation turbine engine can be effectively reduced, then the number of stages of a gas compressor and a turbine is reduced, the mass of the engine is reduced, the thrust-mass ratio of the engine is increased, finally, the performance of the engine is improved, and the iteration period of the overall design of the pulse detonation turbine engine is effectively shortened.

The invention relates to the technical field of energy storage, in particular to a high-temperature energy storage system coupled with an electric cooker and a heat pump system, which comprises a wind power plant, a fused salt heat storage module connected with the wind power plant, a heat pump heat storage module connected with the wind power plant, and a steam power circulation module connected with the fused salt heat storage module and the heat pump heat storage module, wherein the heat pump heat storage module comprises a compressor connected with the wind power plant and an expansion machine connected with the compressor, and a heat regenerator and a cold supply heat exchanger are connected between the expansion machine and the compressor. The respective suitable heat storage temperatures of the fused salt heat storage system and the heat pump heat storage system are reasonably utilized, and compared with a traditional high-temperature heat pump energy storage system, under the condition that the initial parameters of a steam turbine of a steam power circulation system are guaranteed, the heat storage temperature of heat pump heat storage is effectively reduced, the parameters such as the pressure ratio of a compressor are reduced, and the energy efficiency is improved. And the design and manufacturing cost of the compressor is reduced, and the safety and stability of the system are improved.

The application provides a composite medium high-temperature heat pump circulation system and method. The composite medium high-temperature heat pump circulation system comprises: a regenerator connected with a separator; a primary compressor connected with a first outlet of the regenerator and used for preliminarily compressing a nitrogen-poor gas-phase working medium; an ejector, an injection inlet of which is connected with an outlet of the primary compressor, and a material inlet of the ejector is connected with a second outlet of the regenerator; a secondary compressor connected with an outlet of the ejector; and a condenser connected with an outlet of the secondary compressor and used for heat exchange, wherein high-temperature hot water or steam generated through heat exchange is directly delivered to a next device; and supercritical fluid discharged from the condenser is returned to the regenerator for heat exchange and then reenters the separator. By introducing appropriate nitrogen into carbon dioxide as an auxiliary component, the temperature rise amplitude of the mixed working medium in the compression process can be effectively improved.

This invention relates to the field of refrigeration equipment technology, specifically to a compressor anti-surge control method and an air conditioner. The compressor anti-surge control method provided by this invention is applied to a refrigeration system, which includes a compressor and a bypass valve connected in parallel with the compressor. The compressor anti-surge control method includes a compressor start-up control method; specifically, the bypass valve is first opened to a first preset opening degree, and then the compressor is started. Under the action of the bypass valve, the high-pressure gaseous refrigerant discharged from the compressor exhaust port is bypassed back to the inlet port. This reduces the rate of pressure increase at the exhaust port while increasing the pressure at the inlet port, thereby reducing the compressor's pressure ratio and ensuring that the compressor's actual output frequency is always greater than the surge frequency at which compressor surge occurs, thus preventing compressor surge. When the compressor speed is greater than or equal to the minimum starting speed, the compressor is considered to have completed starting, and at this time, the bypass valve is closed at a preset closing speed.

The invention provides an air conditioning system and an electric vehicle thereof.The air conditioning system comprises a compressor, an outside-vehicle heat exchanger, an inside-vehicle heat exchanger, a throttling element, a gas-liquid separator, an ejector and a pressurizer, when the air conditioning system operates in a refrigeration mode, the outside-vehicle heat exchanger is connected between an exhaust port of the compressor and a working fluid inlet of the ejector in series, and the inside-vehicle heat exchanger is connected between the exhaust port of the compressor and the working fluid inlet of the ejector; a liquid outlet of the gas-liquid separator is communicated with an inlet of the in-vehicle heat exchanger through the throttling element, a gas outlet of the gas-liquid separator is communicated with a gas suction port of the compressor, an outlet of the in-vehicle heat exchanger is communicated with an ejection fluid inlet of the ejector through the supercharger, and an ejection outlet of the ejector is communicated with an inlet of the gas-liquid separator. And the operation frequency of the supercharger is adjustable. According to the air conditioning system, the operation power consumption of the compressor is reduced, the battery cruising ability of the vehicle applying the air conditioning system is improved, the pressure of the driving fluid is adjusted by adjusting the operation frequency of the supercharger, and then it is ensured that the arrangement of the ejector can meet the requirements of various operation working conditions.