Measurement of liquid helium heat transfer in a high-speed rotational field and consideration of effect of obstacles blocking channels on the heat transfer

Abstract

The heat transfer of liquid helium is measured in a high-speed rotating field. The centrifugal acceleration is in the range of 900–4600 g. Vertical test surfaces with channel are used, as well as horizontal surfaces. Moreover, for the vertical surfaces with channels, heat transfer is investigated with a blocked inlet and outlet. We examine blocking at the orifice channel outlet and the cover channel inlet for the heat transfer. Results show that heat transfer on vertical surfaces and the upward facing horizontal surface can be approximately represented by correlation equations for constant property fluids. Channel gap size and coriolis force do not affect heat transfer. The heat transfer of a horizontal surface facing downward is 1 6 – 1 7 of the upward facing surface. The orifices and covers for simulating channel blocking have almost no effect on heat transfer. Thus, obstacles blocking the channels do not affect cooling with helium unless blocking is complete.