In contrast to classical dimensional analysis, discriminated dimensional analysis assumes that spatial coordinates are dimensionally independent of each other and allows other types of geometrical quantity to be used in the dimensional basis, such as surfaces and angles. As a consequence, discriminated dimensional analysis leads to a lower number of dimensional groups, which makes the solution more precise. Besides, these discriminated groups have a clear physical meaning in terms of force and energy balances. The paper introduces this technique and provides dimensional equations for the main quantities and physical parameters of the heat transfer and fluid flow fields. Two applications are presented to demonstrate the efficiency of this method.