Abstract: The crescent use of CFD methods in industry and research design have lead to a necessity of obtain detailed information of flow fields. However, the methods utilized in laboratories is often unsuitable for the harsh environment encountered in industry. Therefore, it was developed at INPE a method which utilizes two or three thermocouples to measure fluctuating temperatures and, in addition, obtaining reasonables estimates of the instantaneous velocity. The method consists of the data treatment to reduce the noise and the data reduction itself. It assumes a law for the heat transfer coefficient and the temperature is obtained by using two thermocouples of different diameters. In this work, besides the description of the method, it is presented a simulation of the physical phenomenum and an application of the method in order to compare the method predictions with the correct temperature. The simulation assumes a distribution of frequencies and random errors similar to the ones encountered in experimental situations.