Local heat transfer measurements for two-dimensional ramp geometries were performed in the entrance region of a rectangular channel. Four possible geometries were studied separately. Each geometry included two segments, and each segment consisted of one two-dimensional incline plane (ramp) of 30 degrees incline angle and one flat surface of the same length. For the four configurations studied, the test section projectional length as well as the incline angle were kept constant in order to conclude which configuration would provide better heat transfer for a given pressure drop. Local heat transfer and pressure drop measurements were performed for several Reynolds numbers in the turbulent regime (for one geometry at a time). The heated-coating liquid crystal technique was employed for temperature measurements with heating one segment of each geometry at a time and keeping the rest of the geometry adiabatic. The entire localized data (color plays) were observed and recorded from the top of the channel perpendicular to the test area (90 degrees angle). To support the heat transfer results, flow visualization was also performed using the oil lamp-black technique.
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