Experimental heat transfer and boundary layer measurements on a ceramic matrix composite surface

Ceramic matrix composites (CMCs) are quickly becoming more prevalent in the design of gas turbines due to their advantageous weight and thermal properties. While there are many advantages, the CMC surface morphology differs from that of conventional cast airfoil components. Despite a great deal of research focused on the material properties of CMCs, little public work has been done to investigate the impact that the CMC surface morphology has on the boundary layer development and resulting heat transfer. In this study, a scaled-up CMC weave pattern was developed and tested in a low-speed wind tunnel to evaluate both heat transfer and boundary layer characteristics. Results from these experiments indicate that the CMC weave pattern results in augmented heat transfer and flow field properties that significantly vary locally when compared with a smooth surface.