Heat transfer analysis of shell and tube heat exchanger cooled using nanofluids

Background: In Shell and Tube Heat Exchanger (STHX), heat is exchanged between hot water (coming from industrial outlet by forced convection) to the cold water. Instead of water, if Nano fluids are used into these tubes, then there is a possibility of improved heat transfer because of high thermal conductivity of the nanofluids. Objective: From many literature and patents, it was clear that the study of STHX using metal oxide nanoparticles is very scarce. Therefore, the objective of the present investigation is to check the thermal performance of STHX operated with zinc oxide nanofluid and compare with water as the base fluid. Methods: Heat transfer analysis of a shell and tube heat exchanger was carried out experimentally using Zinc oxide as a nanofluid. Mass flow rate on tube side was varied while on the shell side it was kept constant. Various heat transfer parameters like heat transfer coefficient, heat transfer rate effectiveness and LMTD (Log Mean Temperature Difference) were studied. The experimental readings were record-ed after the steady-state is reached under forced flow conditions. Results: It was found that the effectiveness improves with increase in mass flow rate of nanofluids as compared to base fluid. Conclusion: From the obtained results, it was concluded that heat transfer enhancement and effectiveness improvement does occur with nano fluids but at the cost of pumping power. © 2019 Bentham Science Publishers.