The use of Thermography to Determine the Boundary Conditions of Heat Exchange on The Inner Surfaces of Translucent Enclosing Structures

Abstract

The paper presents an approach to determining the boundary conditions of heat transfer (heat transfer coefficients) on the inner surfaces of translucent enclosing structures using thermal imaging data. To implement this approach, it is necessary to use additional equipment in the form of sheets of paper. A sheet of paper is installed close to and perpendicular to the investigated surface of the structure. At the same time, the profile of the sheet of paper exactly repeats the geometry of the surface under study. Based on the results of thermal imaging, thermograms and temperature graphs are constructed on characteristic areas of the inner surface of the translucent enclosing structure. They are used to determine the thickness of the boundary layer of air adjacent to the inner surface of the translucent enclosing structure. These data are used later to calculate the heat transfer coefficient at the inner surface of these structures. The presented approach was implemented in the course of field studies of heat transfer conditions at the internal surfaces of four PVC windows.