Study On Heat Transfer Performance Of Radial Heat Pipes

The gas-liquid heat transfer process, which the gas flows through finned tube outer wall while the liquid flows in the tube, is a kind of excellent heat transfer mode. In this heat exchanger, only the tube wall separates the cool and warm fluids, results that the wall temperature can not be largely adjusted. So when the wall temperature needs to be largely changed, this heat exchanger is not suitable anymore. The thermal resistance between the gas and liquid can be subjectively increased by longitude heat pipe, and the wall temperature can be lager scale adjusted to avoid water or acid coagulation and further ash accumulation or corrosion.Three pieces of heat pipes with different eccentricities (0, 23% and 34%) are tested in present paper, and the working fluid is water. The effect of heat flux, operation temperature and the liquid full ratio on heat transfer is carefully evaluated.The corresponding times to heat flux of three pieces of heat pipes with different eccentricities are recorded and compared. The results reveal that the heat pipes with eccentricity of 23% and 34% are more sensitive than the heat pipes with 0% eccentricity, and the former two heat pipes can more rapidly than the latter in adjusting wall temperature.The unit thermal resistance of three pieces of heat pipes with different eccentricities are regressed as follows: for 0% eccentricity, R =3839.1t_v^-0.233q_w^-1.237Ω^-0.4996; for 23% eccentricity, R = 21763.58t_v^-0.39q_w^-1.344Ω^-0.279; for 34% eccentricity, R = 39576.58t_v^-0.541q_w^-1.344Ω^-0.436. These relation equations are proved to be correct by test of statistical significance.