An experimental study exploring heat transfer enhancement in tube in tube heat exchanger with pulsating flow

Rationalizing power consumption is crucial in air conditioning and refrigeration design. This study focuses on improving the coefficient of performance (COP) by applying pulsating flow. Experimental trials compared continuous counter and counter pulsating flow to continuous parallel flow, showing a 10% reduction in fluid temperature with continuous counter flow and a 20% reduction with counter pulsating flow. Sensible water heat rejection increased by 10.03% and 19.78% with continuous counter flow and counter pulsating flow, respectively. Overall heat transfer coefficient improved by 57.5% and 75% with continuous counter flow and counter pulsating flow. Effectiveness increased by 4.55% and 10.6%, while COP increased by 4.52% and 13.4% with continuous counter flow and counter pulsating flow, respectively. This research demonstrates the potential of pulsating flow techniques to enhance air conditioning and refrigeration efficiency.