Análise do campo de temperatura para caracterização experimental da concentração da mistura água-álcool

Abstract

The characterization of mixtures containing water and an amphiphilic solute has been widely studied in recent years. The applications in this study play an important role in many engineering applications. This work proposes the determination of the wateralcohol concentration using a periodic temperature field. For this, an experimental device was built with the operating principle in the Angstrom method, which makes use of a periodic heat flow from a controlled source, thus generating a periodic temperature field in the test sample. Thermocouples were installed in the sample and at a reference point to capture the temperature signal generated by the periodic heat flow. The amplitude and phase of these signals will be obtained through a data acquisition system. The thermocouple positioned on the tube wall was adopted as a reference in relation to the thermal signal acquired by the sample thermocouple. Computer simulations were performed based on the theoretical mathematical model, considering the one-dimensional heat conduction to obtain the periodic temperature response measured at the center of the cylindrical tube. The Generalized Integral Transform Technique (GITT) was used to solve the problem of heat diffusion and determine the temperature field, generating theoretical results. The samples used in this work were prepared with volumetric fractions of 0.3, 4.2, 8.2, 12.1, 16.2 and 19.7 %m/m ethyl alcohol mixed with distilled water. The theoretical model developed was used as a reference for the construction of the experimental device.