The Design Method Of Real Gas Three-Port Wave Rotor And Its Integration In Thermal System

The real gas equation of state has been developed for many years since it was proposed.At present,there are relatively mature theoretical methods for the design and performance research of real gas steady flow equipment.However,lack of real gas unsteady wave theory,engineers have to use the ideal gas model to make a preliminary estimate,and then correct the value by means of computational fluid dynamics(CFD).Wave rotor is a kind of equipment works on the process of gas waves’ interaction effects.The ability to exchange the energy directly without the need for mechanical components such as shafts or impellers,makes the wave rotor supercharging technology become a transformative technology in China and has important research significances.While,due to its unsteady characteristics,the CFD simulation of wave rotor is slow and the calculation cycle is long,which seriously delays the production or experiment process.Therefore,it has high research value to develop a real gas wave rotor calculation method.The main research contents and conclusions in this paper are as follows:(1)Propose the calculation method of a single real gas wave like the shockwave and simple wave,then provide the calculation methods for the interaction effects among the expansion waves,compression waves,shock waves and contact faces,also the calculation method of shock tube are given and some of the models are verified by CFD;in the process of simulating the R23/R134 a mixed refrigerants shock tube,it is found that the calculation method used ideal gas EOS has a large error,while the largest error between the method used real gas EOS and CFD is lower than 1%.(2)A three-port wave rotor design code(IGWR/RGWR)was developed based on the ideal gas or real gas equation of state respectively,and compared with the two-dimension CFD simulation.It is found that the maximum error between RGWR and CFD simulation for pressure is about 6%,and for temperature is about 1%,and the error of IGWR calculation is higher than that of RGWR,so the real gas effect must be considered when designing wave rotor equipment;Moreover,from the calculation time-costuming point,RGWR shows clear superiority than the CFD method,so it is suitable for the preliminary parameters calculation of each region in the wave rotor.(3)After applying the RGWR to the calculation of the auto-cascade refrigeration cycle,it is found that the pressure ratio of compressor is reduced by about 21% in the auto-cascade refrigeration cycle enhanced by the wave rotor under the initial conditions in this paper.Also,the auto-cascade refrigeration cycle calculation method with RGWR satisfy the mass conservation,energy conservation of the thermodynamic system and the momentum conservation inside the wave rotor.So it can be used for the thermodynamic and gas dynamics analysis of the auto-cascade refrigeration system that enhanced by the wave rotor.(4)Built the wave rotor experiment platform and conducted a single refrigerant R134 a wave rotor entrainment experiment.The experimental results show that when the wave rotor is turned on,the process of entraining and pressurizing low pressure fluid by high pressure fluid can be realized.Under the experimental conditions,the entrainment ratio is about 9%,the pressurized ratio is about 1.36;when the wave rotor turned off,the high-pressure fluid will flow back into the low-pressure tube,and the pressure of the medium-pressure fluid is closed to the low-pressure fluid.The experimental results prove the feasibility of wave rotors’ working principle.