有机工质透平膨胀机喷嘴的响应面分析优化

Nozzle Optimization for Organic Turbo-Expander by Response Surface Analysis

为了提高有机工质膨胀机的性能,建立了喷嘴型线优化设计平台,并以喷嘴叶片损失系数为性能指标、以喷嘴型线5个控制点的距离参数为设计变量进行了有机透平膨胀机喷嘴的试验设计。采用响应面方法分析了叶片损失系数随型线控制点的变化,揭示了叶片损失系数对喷嘴型线变化的敏感性。研究结果表明:叶片压力面后段、叶片压力面中部、叶片吸力面后段均存在最佳型线,使喷嘴的叶片损失系数较小;在喷嘴的设计过程中,减小喷嘴前段和中段的厚度,可以有效降低喷嘴损失系数;叶片吸力面中段型线的改变对叶片损失系数的影响较大,叶片压力面中段型线的变化对喷嘴损失系数的影响最小。相对于原型喷嘴,采用最优喷嘴型线后叶片损失系数下降了10%。该研究不仅获得了使叶片损失系数较小的喷嘴型线,还能揭示影响喷嘴性能指标的关键因素。

An optimization design platform for the profile of nozzle was established, the vane loss coefficient was taken as the performance index, and the distance parameters of five control points on the profile were considered as the variables to experimentally design the nozzle of organic turbo-expander. The response surface method was adopted to analyze the variation of vane loss coefficient with the distance parameters, and the sensitivity of vane loss coefficient to the distance parameters was also revealed. The optimal profiles for the trailing section of pressure surface, the middle section of pressure surface and the trailing section of suction surface were obtained. The results illustrate that the vane loss coefficient can be efficiently decreased by reducing the thickness of front and middle sections of nozzle vane. The profile variation of middle section of the suction surface greatly affects the vane loss coefficient, while the profile variation of the middle section of pressure surface slightly affects the vane loss coefficient. The vane loss coefficient decreases by 10% in the optimal profile design.