β型斯特林发动机功率影响因素分析

Analysis of influence of various factors on power of β -Stirling engine

为了探究因素对β型斯特林发动机功率的影响,同时研究影响程度及显著性,以Schmidt分析法为基础,对β型斯特林发动机的功率进行理论计算,并针对影响斯特林发动机性能的活塞相位角、行程容积比、死容积比和温度比,利用Matlab编程绘制三维图像,分析两两因素耦合对发动机功率的影响,研究因素之间的相互作用.结果表明:活塞相位角存在最佳值,且此最佳值随行程容积比、温度比的增加分别呈现减小、增大的趋势;行程容积比越大功率越大,且死容积比越小,行程容积比对功率的影响越大,最佳行程容积比为0.5~1.5;死容积比的增加将导致功率降低,死容积比应小于1.5,而行程容积比的增加会使此降低幅度增大,温度比的增加使此降低幅度减小;功率随温度比的增大而减少,最佳温度比应小于0.5.最后,利用正交试验设计分析4个因素的影响作用大小及显著性,得到温度比和行程容积比相对显著的结果.

The influence of various factors on the power ofβ-Stirling engine was studied.Based on Schmidt analysis,the power of aβ-Stirling engine was calculated theoretically.Four factors affecting the performance of Stirling engine,namely,piston phase angle,stroke volume ratio,dead volume ratio and temperature ratio.Matlab programming was used to draw 3D surfaces of the results,and the effect of coupling of two factors on engine power was analyzed,eventually the interaction between factors was obtained.The results show that there is an optimum piston phase angle,which is decreased with increase of volume ratio,but rises with increase of temperature ratio.The larger the stroke volume ratio,the greater the power.The smaller the dead volume ratio,the greater the influence of stroke volume ratio on the power.The optimal stroke volume ratio is ranged in 0.5-1.5.An increase in dead volume ratio results in a decrease in power and the dead volume ratio should be less than 1.5.An increase in stroke volume ratio amplifies the extent of this decline.However,an increase in temperature ratio suppresses the extent of the decline.The power decreases with increase of temperature ratio and the optimum temperature ratio should be less than 0.5.Finally,the effect and significance of four factors are analyzed by employing orthogonal experimental design,and the temperature ratio and stroke volume ratio are relatively significant in the results.