Experimental investigation and performance optimization of thermo-hydraulic and exergetic characteristics of a novel multi-fluid heat exchanger

In this research, the thermo-hydraulic performance of a multi-fluid heat exchanger is experimentally investigated in regard to variations in control parameters, namely flow rate, flow configuration, and inlet temperature. A brazed helix tube (BHT), constructed from a helical coil tube with precision brazing between successive coil turns, is novel and integrated inside the present novel multi-fluid heat exchanger (NMFHE). The NMFHE presented here is part of a residential heating system where concurrent heating of cold water (HF2) and cold air (HF3) takes place with effective heat transfer from hot water (HF1) flowing inside the BHT. The JF factor and entropy generation number (Ns) are considered the key performance parameters of the study and experimentally predicted with respect to variations in control factors. The HF1 flow rate, HF2 flow rate, and flow configuration are identified as the most effective parameters for the JF factor (HF1, HF2, and HF3) with a contribution of 58.67