摘要
周向涡轮结构简单,适应于微型化。为了对发展出的周向六叶片微型涡轮结构进行评价和改进以及分析叶顶间隙对流动的影响,对其内部流场建立三维瞬态数值仿真模型,仿真其输出特性和内部工质流动特性。发现六叶片涡轮存在结构缺陷,运转时进出口周期性连通,部分工质未做功即排出。改进出八叶片微型涡轮,并对其进行仿真,结果显示八叶片涡轮没有上述缺陷。对不同叶顶间隙涡轮内流场进行仿真,结果表明叶顶相对间隙对压力损失的影响呈现非线性关系,间隙小于0.01后,压力损失对间隙变化非常敏感;间隙大于0.02后,其对压力损失的影响已经非常小。仿真和实验结果都表明,八叶片涡轮和六叶片涡轮输出机械功率随工质流量的增加而增加。八叶片涡轮最大机械功率为1 355mW,较六叶片涡轮提高10.5%,八叶片涡轮功率启动输出的流量为140L/h,小于六叶片涡轮的200L/h,八叶片涡轮性能优于六叶片涡轮。
Circumferential micro-turbine adapts to miniaturization as it has simple structure.To evaluate and improve the six-blade micro-turbine structure and analyze the influence of tip clearance on the flow,To simulate the output characteristics and gas flow characteristics,a three-dimensional transient numerical simulation model is set up and the output characteristics and gas flow characteristics are simulated.Results show that the six-blade turbine has structural defect.Parts of gas directly exhaust without working because intake port and exhaust have periodic connectivity while running.Simulation results for the improved eight-blade micro-turbine reveal that it hasn＇t such defects.Then,the effect to pressure drop of tip gap is simulated,and results show that the influence is nonlinear.As the gap is less than 0.01,the pressure drop is very sensitive to the gap.When gap is greater than 0.02,its impact is very small.Simulation and experimental results both show that the output mechanical power of the eight-blade turbine and six-blade turbine increases with the increase of gas flow.The eight-blade turbine mechanical power is 1 355 mW,which is increased 10.5% over the six-blade turbine.The power output start flow of eight-blade turbine is 140 L/h,while that of six-blade turbine is 200L/h.The performance of eight-blade turbine is better than that of six-blade turbine.
出处
《重庆大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2013年第7期1-5,共5页
Journal of Chongqing University
基金
国家自然科学基金资助项目(51175530)
关键词
微能源系统
微型涡轮
数值仿真
动网格
power MEMS
micro-turbine
numerical simulation
dynamic grid
