Investigation on heat transfer characteristics of spiculate lamilloy internal surfaces

Experiment was carried out to analyze the heat transfer characteristics of the inner surfaces of a kind of lamilloy configuration by using narrow-band transient liquid crystal technique. In this research, the ratio of hole pitch to impingement hole diameter (S/D) is 3.2, 4.5, 5.9, and Reynolds numbers range from 10 000 to 40 000. This paper also compared with traditional lamilloy model to analyze the heat transfer mechanism. The result shows that: heat transfer coefficient of the surfaces increases when Re becomes greater, and gradually decreases when the holes pitch becomes wider. The mathematics fit formulas of the Nu with respect to Re and S/D has also been given.