Performance assessment on double pipe heat exchanger with longitudinal groove

Abstract

Thermal performances were performed as preliminary research on double pipe heat exchanger with low number of longitudinal groove. The objective of this work is to determine optimal heat transfer parameter especially logarithmic temperature difference (LMTD) as a time series function. The thermal analysis in this paper also provide total number of heat absorb in the cold fluid. The rectangular-longitudinal grooves were incised on outer surface of tube side with number of longitudinal grooves of 2. The grooves high and width were kept constant at 0.3 mm and 1 mm respectively. The tube made of aluminium with outer diameter is 20 mm. The shell is made of acrylic which has 26 mm in internal diameter. Water is used as the working fluid with counter flow scheme. The volume flowrate of cold fluid was varied from 18x10^-5 m^ 3/s up to 25x10^-5 m^ 3/s which are equal to Reynold number (Re) around 31981 to 43610. The volume flowrate of hot fluid remains constant at 25x10^-5 m^ 3/s which is equal to (Re) around 30904. The LMTD of 2 grooves double pipe heat exchanger was better compared to that of the smooth one since the thermal sectional area are increased which essentially cause larger heat transfer.