Introduction to Convective Heat Transfer

5Dimensional Analysis

5.1 Introduction

We may use the following methods to solve convective heat transfer problems.

1. Analytical or numerical solution is used to obtain the temperature distribution. Here, temperature gradient at the wall is used to determine the heat transfer coefficient.
2. Analogy between mass, momentum, and heat transfer. Here, analogy coupled with wall friction or mass transfer measurements provides the heat transfer coefficient. We will study this topic later.
3. Dimensional analysis. In the absence of an analytical solution or analogy between heat and momentum transfer, we then use experimental methods. The heat transfer coefficient is obtained from the correlation of experimental data.

Convection heat transfer is heavily involved with experimental testing if the analytical or numerical solution does not provide accurate results. This is especially true in turbulent and separating flow heat transfer. Solutions obtained by computational heat transfer yield only fair approximations for turbulent heat transfer. If we have a good understanding of the problem and are able generate a mathematical model but we are having problem generating a solution, it is a good idea to use experimental analysis. Therefore, there is strong need for experimental study in convection heat transfer. If more than three parameters influence a convective heat transfer problem, it becomes very difficult to study the effect of each parameter on the problem. For this reason, if an engineer ...