Measurements of endwall heat transfer in a rectangular passage with 60-degree ribs and suction holes were conducted by using the transient thermochromic liquid crystal technique. The effects of Reynolds number and suction ratios on the heat transfer were investigated under the conditions of main-flow Reynolds number 20 000-80 000 and suction ratio 0-0.6. Our results show that heat transfer is enhanced near suction holes. The average heat transfer coefficient and the enhancement factor rose slightly first and then decreased with the increase in the suction ratio at a given Reynolds number. At a given suction ratio

the average heat transfer coefficient increased linearly and the enhancement factor decreased with the increase in Reynolds number.