TGrid Induced Turbulence in Water Flow
Within a heat exchanger, it is desirable to have a high transfer of heat between the fluids in order to optimize performance and minimize the size of the heat exchanger. Using a vortex generator it is possible to introduce turbulence to increase the heat transfer coefficient. By using the Turbulence decay law1 it is possible relate the intensity of turbulence as a function of distance from the grid. The type of vortex generator investigated in this report is called a turbulence grid. The use of turbulence grids for flows of water has so far not been investigated. We will investigate the problem using CFD simulations validated by experiments using Particle Image Velocimetry. The study will include the impact of hydraulic diameter for the turbulence grid and comparisons with previous studies2 that investigate the turbulence decay law with air as the fluid. The goal of the report is to gain better understanding in the use case of turbulence grids for heat exchanger in order to increase heat transfer. This could reduce the investment cost of heat exchangers by reducing the required transfer areas.