A comparative experimental study on the performance of staggered tube-bundle heat exchanger with unequally-pitch and equally-pitch arrangement in oscillating flow

摘要

A novel staggered tube-bundle seawater heat exchanger with unequally-pitch arrangement, which the transversal and longitudinal tube pitches are inhomogeneous, is firstly proposed and applied in the closed-loop seawater source heat pump system. An experimental system that can induce the regular wave to simulate the seawater flow is established to investigate the thermal resistance ratio, overall heat transfer coefficient, thermal efficiency of heat exchanger under various wave parameters. The thermal performance, hydraulic performance, and comprehensive thermal-hydraulic performance of heat exchangers with unequally-pitch arrangement and equally-pitch arrangement are compared. The results indicate that the unequally-pitch arrangement of tube-bundle heat exchanger can significantly enhance the overall heat transfer coefficient and thermal efficiency, meanwhile decrease the pressure drop, and consequently improve the comprehensive performance. The present study is conducive to improve the performance potential of staggered tube-bundle seawater heat exchanger and promote the exploitation of ocean thermal energy.