Heat transfer behaviour on influence of an adiabatic section on concentric tube shell assisted heat pipe heat exchanger

Abstract

ABSTRACT Thermal performance of the concentric tube shell assisted heat-pipe heat exchanger with and without adiabatic section has been experimentally investigated. Water is used as a heat-carrying fluid and methanol is used as a working fluid in the heat pipe. Mass flow rates of hot water range from 30 to 70 lph and those of cold water from 15 to 35 lph and during the investigation the temperature of the hot water at inlet ranges from 50to –60°C. For various mass flow rates and inlet temperatures, the heat transfer coefficient, heat transfer rate and effectiveness of the heat exchanger are reported. The mass flow rate of hot and cold water is 70 and 35 lph, respectively, and that of the inlet hot water is 60°C, the effectiveness of heat pipe without adiabatic section is 26.9%. The investigation reveals that there is an increase in effectiveness by 11.2% in non-adiabatic section, compared with adiabatic section.