Numerical Investigation on Mechanism of Heat Transfer Augmentation in Lamilloy

A simplified heat transfer model was used to analyze Lamilloy cooling characteristics.The results show that the parameter f,adiabatic effectiveness of film cooling at gas side and the internal heat transfer efficiency are important parameters in the design optimization.In order to learn how the internal flow patterns affect the overall cooling effectiveness of Lamilloy,conjugate numerical simulation were carried out for a double wall without pin fin and five Lamilloy cooling configurations with the same hole diameter,spacing and pin fin height.The numerical results show that Lamilloy have higher cooling effectiveness than the double wall.The coolant through the walls took off most of the heat, transferred from hot gas to the Lamilloy,and the heat transfer on internal surface of outlet plate was the major mechanism to remove the heat.The existence of pin fin increases heat transfer area and the amount of heat transfer in Lamilloy, and the uniformity of temperature in Lamilloy can be improved by proper design of pin fin.