[关键词]
[摘要]
透平作为循环输出功部件,是超临界二氧化碳(SCO2)布雷顿循环的核心部件之一。本文通过与美国Sandia实验室SCO2径流透平实验数据对比,确定了高精度数值模拟计算模型-SST(Extended wall function)湍流模型。并以此为据,针对SCO2布雷顿循环径流透平,对比数值模拟结果重点分析了冲角损失、转子通道损失与间隙泄露损失,确定了适用于SCO2工质的损失模型组合。其中冲角损失选择WasserbauerGlassman模型,最佳冲角计算选用Chen的滑移模型;转子通道损失选用CETI模型,间隙泄露损失选用Jansen模型。根据选用损失模型对高压级和低压级两种工况的透平进行多工况流量和等熵效率预测并与数值模拟结果对比。结果表明:高压级透平最大偏差不超过2.4%和1.5%,低压级透平最大偏差不超过2.1%和1.2%。
[Key word]
[Abstract]
Turbine,as the cyclic output power component,is one of the core components of the supercritical carbon dioxide (SCO2) Brayton cycle.This paper determines a highprecision numerical simulation calculation modelSST(extended wall function)turbulence model by comparing with the experimental data of the SCO2 radialinflow turbine from Sandia Laboratory in the United States. On this base,by comparing with numerical simulation results,the incidence loss,rotor passage loss and tip clearance loss for the SCO2 Brayton cycle radialinflow turbine are analyzed emphatically,and the loss model combination suitable for SCO2 working fluid is determined. The WasserbauerGlassman model is selected for incidence loss,the best angle of incidence is calculated by Chen model; the CETI model is selected for rotor passage loss,and the Jansen model is selected for tip clearance loss. According to the selected loss model,the multicondition flow rate and isentropic efficiency predictions of the highpressure and lowpressure turbines are carried out and compared with the numerical simulation results. The results show that the maximum deviation of the highpressure turbine does not exceed 2.4% and 1.5%,and the maximum deviation of the lowpressure turbine does not exceed 2.1% and 1.2%.
[中图分类号]
TK14
[基金项目]
国家自然科学基金面上基金项目资助(52176090);中国科学院洁净能源先导科技专项资助(XDA21010201)