Numerical Analysis of Plate Fin Heat Exchanger at Cryogenic Conditions

Abstract

Compact heat exchangers, especially plate fin heat exchangers (PFHE) are playing an important role in various fields of science and technology. Especially in cryogenics with its high compactness providing very high degree of heat exchange area per unit volume (of the range of 1000m2/m3) and high effectiveness of 0.95 and above, PFHE is one of the most desirable equipment in the cryogenic field. Various forms of flow configurations and heat transfer surfaces for the PFHE have been studied and used. In this investigation PFHE of Aluminium alloy Al-3003 with rectangular offset-strip fin is simulated by the cold layer test method to find the effectiveness and pressure drop at low temperatures using liquid Nitrogen i.e. of the range of 80K-110K as the inlet temperature of the cold fluid and inlet of hot fluid at room temperature (taken to be at 315K). Simulated prediction is done using simulation software Aspen MUSE. The comparison between the cold layer test and hot layer test is done and their performance factors like effectiveness and pressure drop are compared. Results obtained from the simulation software Aspen MUSE show that at low temperatures a high effectiveness is displayed by the test PFHE with pressure drops under the prescribed limits. Also mass flow rate at which experimentation can be carried out is also found out.