Numerical analysis of the heat pump water heater with immersed helically coiled tubes

Abstract

With the aim of increasing the accuracy of the numerical results and reduce the computational time of simulation, our work focuses on the study of a heat pump water heater with immersed helically coiled tubes. The effects of the storage tank dimension and the copper coil pitch on the heating process were investigated by considering the evolution of temperature and velocity field of the waterside at the axial centerline of cylindrical water tank. The effects of varying the time step on the evolution of the average water temperature and velocities during the heating process are analyzed using Computational fluid dynamics (CFD) software package. The results showed that the effects of time step size on the results and clearly led to less accuracy. The validation of the numerical solutions was performed by comparing the simulated average water temperature with the results reported from the literature [1,2].It was found that the simulation and experimental results are in good agreement.