Z.C. Liu

Experimental Investigation of Temperature Oscillation in Miniature Loop Heat Pipe

Temperature oscillations are a rather wide‐spread phenomenon accompanying the mLHP operation, which depend on the charging ratio of the working fluid, the device orientation in the gravity field and the conditions of the condenser cooling, and so on. Intense oscillation, whose amplitude may exceed tens of centigrade degrees and the period maybe equal to tens of minutes, arise from the lack of a working fluid in a mLHP when a hot condensate or vapor bubbles periodically penetrate into the compensation chamber and act on the vapor phase in it, which increasing its temperature and volume. Changes in the external conditions, for instance, the LHP arrangement in an unfavorable orientation or applied heat load with respect to the conditions for which the filling volume is optimal, also contribute to the initiation of intense temperature oscillation. All in all, the heat leak from the evaporator to the compensation chamber, the heat loss to ambient and the temperature and rate of subcooled liquid dictate the vap...