Measurements of endwall heat transfer in pin-fin array duct with lateral-flow by using transient liquid crystal technique

Measurements of endwall heat transfer in pin fin array duct with lateral-flow are made by using transient liquid crystal technique. The effects of Reynolds number and lateral-flow ratio on the heat transfer are investigated. The lateral-flow Reynolds numbers range from 3 × 10⁴ to 9 × 10⁴ and lateral-flow ratios range from 0.25 to 1.0. Results show that: (1) The lateral-flow ratio effects on the flow state and endwall heat transfer in pin fin array duct are important. (2) A critical lateral-flow ratio is found. The pin fin array flow is in staggered flow state in the mainstream flow direction when the lateral flow ratio is lower than this critical ratio. The pin fin array flow is in staggered flow state in the lateral-flow direction when the lateral flow ratio is higher than this critical ratio. The pin fin array flow is in aligned flow state in the flow direction between mainstream and lateral flow when the lateral flow ratio is equal to this critical ratio. (3) When the lateral flow ratio is higher or lower than the critical ratio, the average endwall heat transfer coefficients are higher. When the lateral flow ratio is close to the critical ratio, the average endwall heat transfer coefficients are lower.