Temperature distribution in thermal boundary layers (in free convection) using a modified Schlieren method

A simple optical apparatus, the Schlieren interferometer, was constructed for the quantitative investigation of free convection heat transfer from solid bodies. The photographic results, checked by using thermocouples, were used in evaluating the temperature distribution, the key to the solution of these problems. Interpretation of the photographic results was made using the simple calculation for the conventional interferogram and the Dale-Gladstone law. Although the experiments were limited to a heated flat plate and a heated wire, two dimensional test pieces of irregular configuration can be investigated by the same apparatus with simple modifications. The photographs of the conventional Schlieren, the color Schlieren, and the modified Schlieren were compared using the same apparatus and they reveal that the Schlieren interferometer is a powerful tool for compressible fluid flow investigation --Abstract, Page iii