Abstract

Optimal exchanger selection and performance analysis for heliumwater heat transfer in fusion energy applications

Author(s): KarishmaAnand, Rupsha Bhattacharyya,K.C.Sandeep

Plate heat exchangers (PHEs) and double pipe heat exchangers (DPEs) are possible alternatives for gas-liquid heat transfer applications, particularly for relatively low heat duties of the order of few hundred Watt. One such application is cooling of the helium coolant gas used for heat removal from the first wall of tritium breeder blankets in fusion reactors, before the gas is purified. This work illustrates the selection of an optimal heat exchanger out of PHEs and DPEs for this application based on the total exchanger cost and floor space requirement. Heat transfer area requirements and pressure drop are predicted using appropriate Nusselt number and friction factor correlations. Preliminary cost estimations are made by considering the purchase cost of each unit and the cost of electrical energy required for fluid pumping. Thus the most economical PHE and DPE are identified. The PHE and DPE are then compared on the basis of space requirements. Effects of various design and operating parameters on the total cost of the optimal exchanger type have been evaluated. Heat exchanger effectiveness and exergy analyses have also been performed as part of the rating exercise for the optimal exchanger.