This paper shows some preliminary experimental results of a single turned PHP operating in a vertical mode with the condenser and the evaporator connected with flexible pipes. The inner diameter of these pipes is 2 mm and the working fluid used in the experiments is water. For each test a high speed imaging acquisition has been carried out. In this experiments no misalignment between evaporator and condenser has been tested. Thermal resistances of 1.96-2.80 K/W have been observed. The experiments have shown which the flexible pipes make unsymmetrical the device so that a preferential direction in the circulation has been observed. Four different steady regimes have been observed equal to those highlighted in similar devices. The most common operative regime is characterized by alternating periods of fluid circulation and periods without any circulations, while the steady state without any stationary period have been rarely observed. The flow patterns of the water PHP show small vapour plugs which are long as the inner diameter of the capillary pipes. This behaviour could be induced by the flexible pipes
Pulsating Heat Pipes with Flexible Adiabatic Section: First Experimental Results
FILIPPESCHI, SAURO;
2010-01-01
Abstract
This paper shows some preliminary experimental results of a single turned PHP operating in a vertical mode with the condenser and the evaporator connected with flexible pipes. The inner diameter of these pipes is 2 mm and the working fluid used in the experiments is water. For each test a high speed imaging acquisition has been carried out. In this experiments no misalignment between evaporator and condenser has been tested. Thermal resistances of 1.96-2.80 K/W have been observed. The experiments have shown which the flexible pipes make unsymmetrical the device so that a preferential direction in the circulation has been observed. Four different steady regimes have been observed equal to those highlighted in similar devices. The most common operative regime is characterized by alternating periods of fluid circulation and periods without any circulations, while the steady state without any stationary period have been rarely observed. The flow patterns of the water PHP show small vapour plugs which are long as the inner diameter of the capillary pipes. This behaviour could be induced by the flexible pipesI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
