可逆式水泵水轮机泵工况的驼峰特性.docx

可逆式水泵水轮机泵工况的驼峰特性陶然1 ，肖若富1 ，杨魏1 ，刘伟超2( 1． 中国农业大学水利与土木工程学院，北京 100083; 2． 东方电机有限公司，四川 德阳 618000)陶然陶然，肖若富，杨魏，等． 可逆式水泵水轮机泵工况的驼峰特性［J］． 排灌机械工程学报，2014，32( 11) : 927 － 930，936．Tao Ｒan，Xiao Ｒuofu，Yang Wei，et al． Hump characteristic of reversible pump-turbine in pump mode［J］． Journal of Drainage andIrrigation Machinery Engineering( JDIME) ，2014，32( 11) : 927 － 930，936． ( in Chinese)Hump characteristic of reversible pump-turbine in pump modeTao Ｒan1 ，Xiao Ｒuofu1 ，Yang Wei1 ，Liu Weichao2( 1． College of Water Ｒesources and Civil Engineering，China Agricultural University，Beijing 100083，China; 2． Dongfang Electric Ma- chinery Co． Ltd． ，Deyang，Sichuan 618000，China)Abstract: To investigate the hump characteristic in discharge-head curve of reversible pump-turbinesin pump mode，the internal flow field of a pump-turbine unit is simulated in its pump mode under dif- ferent flow-rate conditions by employing the detached eddy simulation ( DES) method． The underlying mechanism for the hump characteristic is exploited by comparing the CFD and experimental characteris- tics of flow inside each passage of the unit，especially for the hydraulic losses in the diffusing passageand for the rotor-stator interaction． The results show that the flow exhibits an obviously asymmetric pat-tern at the runner outlet as the unit is operated in the low discharge range． The asymmetric flow field is caused from the vortex and secondary flow generated in the diffusing portion of the runner passages． As a result，the hydraulic losses in the unit rise dramatically，causing a reduction in the pump head，e- ventually the hump characteristic occurs． Nevertheless，improving the flow pattern under the low dis- charge conditions can be very helpful to mitigate or eliminate the hump characteristic． The mechanism for the hump characteristic has been enunciated here． This may be referential and helpful to improve the hydraulic performance and conducive to enhance the operating stability of a reversible pump-tur