Air curtain temperature measurement in an open refrigerated display cabinet by IR thermography

IR thermography has been widely used to measure air temperature in many application fields. Usually screens or targets are located in the region of interest in such a way to minimise the perturbation of the flow under investigation. In this work, this technique is applied to map the air distribution inside the cold curtain of an open refrigerated display cabinet. The performances of a black cardboard, which is commonly used, and a net-screen are studied in different conditions by a computational fluid dynamics analysis. Experimental measurements are carried out on the cold curtain, both with the cardboard and the net-screen. The comparison of results is reported. The analysis shows that this measurement technique is highly intrusive from the fluid-dynamic point of view, and the error due to the surrounding radiation is significant.