Characteristics of heat transfer in helium gas enclosed disk enclosure

Experimental results of heat transfer in helium-gas-enclosed disk enclosure (DE) are described. The following results were obtained. (1) The windage loss of a DE containing helium gas is about one fifth of that of a DE containing air. This effectively decreases DE temperature and disk runout. (2) The temperature increase of the positioner coil in helium gas is about one half of that in air. (3) Smaller windage loss and high conductivity minimize helium gas locational temperature dependence.<
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