Combined film and impingement cooling of flat plate with reverse cooling hole

Singh, Kuldeep; raj, Uday

Abstract

A numerical model is developed in the present work for analysing cooling performance of combined impingement-film cooling under realistic engine operating conditions. Effect of jet impingement along with the film cooling is analysed on fluid flow, heat transfer, cooling performance and pressure drop for forward and reverse orientations of the cooling hole. Further, effect of hole orientation on the cooling performance is studied under wide range of blowing ratios and jet-to-plate spacings. It is observed that the effect of jet impingement is significant on the cooling performance. Surface temperature of the metallic plate is found to be 50–90 °C lower for the combined jet impingement and film cooling case as compared to the only film cooling case. The improvement in the heat transfer for combined impingement-film cooling is at the cost of increased pressure drop. Film cooling effectiveness for the case of combined impingement-film cooling is found to be dependent on the hole orientation and blowing ratio. The secondary jet penetration into the mainstream increases with increase in the blowing ratio/velocity ratio. Kidney-vortices are formed at a velocity ratio of 1.07 from forward injection which resulted in decreased film cooling effectiveness. These kidney-vortices were not formed for the case of reverse injection and coolant spreads uniformly in the transverse direction. At lower velocity ratios when formation of kidney vortices is not prominent, forward injection results in better film cooling effectiveness compared to the reverse injection. Gas radiation is also considered in the modelling and its effect is found significant on the temperature prediction of the components.

Citation

Singh, K., & raj, U. (2023). Combined film and impingement cooling of flat plate with reverse cooling hole. Applied Thermal Engineering, 208, Article 118224. https://doi.org/10.1016/j.applthermaleng.2022.118224

• Journal Article Type: Article
• Acceptance Date: Feb 13, 2022
• Online Publication Date: Feb 26, 2022
• Publication Date: Sep 25, 2023
• Deposit Date: Mar 24, 2022
• Publicly Available Date: Feb 27, 2024
• Journal: Applied Thermal Engineering
• Print ISSN: 1359-4311
• Electronic ISSN: 1873-5606
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 208
• Article Number: 118224
• DOI: https://doi.org/10.1016/j.applthermaleng.2022.118224
• Keywords: Industrial and Manufacturing Engineering; Energy Engineering and Power Technology
• Public URL: https://nottingham-repository.worktribe.com/output/7648555
• Publisher URL: https://www.sciencedirect.com/science/article/pii/S1359431122001867
• Additional Information: Received 30 September 2021, Revised 23 January 2022, Accepted 13 February 2022, Available online 22 February 2022, Version of Record 26 February 2022.