Measurements and Numerical Simulations of Heat Transfer and Pressure Drop in a Duct With Smooth Walls

Accurate measurements of heat transfer and pressure drop play important roles in thermal designs in a variety of pipes and ducts. In this study, the convective heat transfer coefficient was measured with a semi-local surface average based on Newton’s Law of cooling. Flow and heat transfer data for different Reynolds numbers were collected and compared in a duct with smooth walls. Pressure drop was measured with a pressure transducer from OMEGA Engineering Inc. The experimental results were compared with numerical estimations generated in ANSYS Fluent. Fluent contains the broad physical modeling capabilities needed to model heat transfer and pressure drop in the duct. Thermal conduction and convection in the three-dimensional (3D) duct are simulated together. Special cares for selecting the viscosity models and the near-wall treatments are discussed. The goal of the paper is to find appropriate numerical models for simulating heat conduction, heat convection and pressure drop in the duct with different Reynolds numbers. The relationship between the heat transfer coefficient and Reynolds numbers is discussed. Heat flux and inlet temperature measured in the experiment are applied to the boundary conditions. The study provides the unique opportunity to verify the accuracy of numerical models on heat transfer and pressure drop in ANSYS Fluent.