单项选择题
A.throttling the pressure line B.changing the speed of the rotor C.either A or B D.None of the above is tree
While flowing through the volute in a centrifugal pump,...
单项选择题While flowing through the volute in a centrifugal pump, part of the （） energy of the liquid is converted to （） energy.
A.kinetic；pressure B.kinetic；essential C.pressure；kinetic D.pressure；height
The amount of fluid delivered by a screw pump can be re...
单项选择题The amount of fluid delivered by a screw pump can be regulated by （）.
A screw pump belongs to （） according to its working pri...
单项选择题A screw pump belongs to （） according to its working principle.
A.reciprocating pumps B.positive displacement pumps C.centrifugal pumps D.centripetal pumps
