Study On Coupling Performance Of Stirling Engine Thermodynamic Parameters

In dish-type,tower-type,Fresnel-type,and trough-type photo-thermal power generation systems,the dish-type system has the highest photoelectric conversion efficiency,and has attracted attention because of its advantages of no pollution,low noise,and the use of multiple energy sources.The Stirling engine is the key equipment of the dish-type solar power generation system and can be divided intoαtype,βtype andγtype according to the structure.This article studies theβ-type Stirling engine,from the perspective of the energy transfer,based on the Schmidt theory,ideal adiabatic model and polytropic model,conducts dynamics and thermodynamic analysis on the heater,regenerator and cooler,hot chamber and cold chamber,and whole machine of Stirling engine to obtain the relationship of the operating parameters such as temperature and pressure and the structural parameters such as phase angle,crank angle and dead volume ratio to the engine power and efficiency,and calculate the coupling relationship between the factors that affect the system performance.Based on the Schmidt model,the impacts of the factors such as temperature ratio,pressure,rotational speed,phase angle,stroke volume ratio,and dead volume ratio on engine performance are coupled and analyzed.The orthogonality test analysis method is used to verify the primary and secondary relationship and significance of the influencing factors,such as phase angle,stroke volume ratio,temperature ratio and dead volume ratio.The calculation results show that the smaller the temperature ratio is,the better the engine performance is;the greater the pressure and rotation speed is,the higher the engine power value is;with the gradual increase of the phase angle,the engine power is increased first and then decreased;there have best ranges for the stroke volume ratio and the dead volume ratio.The impact of the stroke volume ratio on the engine power is maximum,the impact of the phase angle is minimal.When k_s=1.5、?=0.25、χ=1.0、80°≤α≤95°,the engine can output maximum power.Based on the ideal adiabatic model,the fourth-order Runge-kutta method is used to analyze the operation of the Stirling engine and the loss of heat transfer,shuttle heat loss of the displacer,regenerator returning heat loss of the GPU-3 engine is calculated.The power variation of the engine with different working fluid using helium,hydrogen and air is compared.And the Schmidt method and the adiabatic analysis method are compared.The results show that the heat transfer loss is the largest among all engine losses,and regenerator returning heat loss is the largest.And the power is better when the engine is using helium.The power calculated by the adiabatic model is smaller than the Schmidt method.By analyzing the impacts of multiple parameters on the power and efficiency of the Stirling engine,the optimal parameter range was obtained,and the working performance of the Stirling engine was optimized,laying the foundation for the engineering application of the dish-type solar Stirling power generation system.