Enhancement of Film Cooling Effectiveness in a Supersonic Nozzle
Film cooling as applied to rocket nozzles is analyzed numerically with emphasis on the assessment of the effect of the mixing of coolant with the hot stream. Cooling performance, as characterized by cooling effectiveness, is studied for three different coolants in the three-dimensional, turbulent fl...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
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MDPI AG
2023-03-01
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| Series: | Entropy |
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| Online Access: | https://www.mdpi.com/1099-4300/25/3/481 |
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| author | Nithin Somasekharan A. R. Srikrishnan Harihara Sudhan Kumar Krishna Prasad Ganesh Akram Mohammad Ratna Kishore Velamati |
| author_facet | Nithin Somasekharan A. R. Srikrishnan Harihara Sudhan Kumar Krishna Prasad Ganesh Akram Mohammad Ratna Kishore Velamati |
| author_sort | Nithin Somasekharan |
| collection | DOAJ |
| description | Film cooling as applied to rocket nozzles is analyzed numerically with emphasis on the assessment of the effect of the mixing of coolant with the hot stream. Cooling performance, as characterized by cooling effectiveness, is studied for three different coolants in the three-dimensional, turbulent flow field of a supersonic convergent-divergent nozzle operating with a hot stream temperature of 2500 K over a range of blowing ratios. The coolant stream is injected tangentially into the mainstream using a diffuser-type injector. Parameters influencing the effectiveness, such as coolant injector configuration and mixing layer, are analyzed. Thermal and species mixing between the coolant and the mainstream are investigated with regard to their impact on cooling effectiveness. The results obtained provide insight into the film cooling performance of the gases and the heat transfer characteristics associated with these three gases. An injector taper angle of 30° results in the most effective cooling among the configurations considered (0°, 15°, 30° and 45°). Mixing of the coolant with the hot stream is examined based on the distributions of velocity, temperature and species. The higher values of cooling effectiveness for Helium are attributed to its thermophysical properties and the reduced rate of mixing with the hot stream. The results further indicate that through optimization of the blowing ratio and the coolant injector configuration, the film cooling effectiveness can be substantially improved. |
| first_indexed | 2024-03-11T06:35:00Z |
| format | Article |
| id | doaj.art-72a7dc7243ed45faa6ec21e3d4eb41c2 |
| institution | Directory Open Access Journal |
| issn | 1099-4300 |
| language | English |
| last_indexed | 2024-03-11T06:35:00Z |
| publishDate | 2023-03-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Entropy |
| spelling | doaj.art-72a7dc7243ed45faa6ec21e3d4eb41c22023-11-17T10:56:49ZengMDPI AGEntropy1099-43002023-03-0125348110.3390/e25030481Enhancement of Film Cooling Effectiveness in a Supersonic NozzleNithin Somasekharan0A. R. Srikrishnan1Harihara Sudhan Kumar2Krishna Prasad Ganesh3Akram Mohammad4Ratna Kishore Velamati5Department of Aerospace Engineering, Amrita School of Engineering Coimbatore, Amrita Vishwa Vidyapeetham, Tamil Nadu 641112, IndiaDepartment of Aerospace Engineering, Amrita School of Engineering Coimbatore, Amrita Vishwa Vidyapeetham, Tamil Nadu 641112, IndiaDepartment of Aerospace Engineering, Amrita School of Engineering Coimbatore, Amrita Vishwa Vidyapeetham, Tamil Nadu 641112, IndiaDepartment of Aerospace Engineering, Amrita School of Engineering Coimbatore, Amrita Vishwa Vidyapeetham, Tamil Nadu 641112, IndiaDepartment of Aerospace Engineering, King Abdulaziz University, Jeddah 21589, Saudi ArabiaDepartment of Mechanical Engineering, Amrita School of Engineering Coimbatore, Amrita Vishwa Vidyapeetham, Tamil Nadu 641112, IndiaFilm cooling as applied to rocket nozzles is analyzed numerically with emphasis on the assessment of the effect of the mixing of coolant with the hot stream. Cooling performance, as characterized by cooling effectiveness, is studied for three different coolants in the three-dimensional, turbulent flow field of a supersonic convergent-divergent nozzle operating with a hot stream temperature of 2500 K over a range of blowing ratios. The coolant stream is injected tangentially into the mainstream using a diffuser-type injector. Parameters influencing the effectiveness, such as coolant injector configuration and mixing layer, are analyzed. Thermal and species mixing between the coolant and the mainstream are investigated with regard to their impact on cooling effectiveness. The results obtained provide insight into the film cooling performance of the gases and the heat transfer characteristics associated with these three gases. An injector taper angle of 30° results in the most effective cooling among the configurations considered (0°, 15°, 30° and 45°). Mixing of the coolant with the hot stream is examined based on the distributions of velocity, temperature and species. The higher values of cooling effectiveness for Helium are attributed to its thermophysical properties and the reduced rate of mixing with the hot stream. The results further indicate that through optimization of the blowing ratio and the coolant injector configuration, the film cooling effectiveness can be substantially improved.https://www.mdpi.com/1099-4300/25/3/481rocket nozzle coolingmixing layer studiesdiffuser-type coolant injectorfilm cooling |
| spellingShingle | Nithin Somasekharan A. R. Srikrishnan Harihara Sudhan Kumar Krishna Prasad Ganesh Akram Mohammad Ratna Kishore Velamati Enhancement of Film Cooling Effectiveness in a Supersonic Nozzle Entropy rocket nozzle cooling mixing layer studies diffuser-type coolant injector film cooling |
| title | Enhancement of Film Cooling Effectiveness in a Supersonic Nozzle |
| title_full | Enhancement of Film Cooling Effectiveness in a Supersonic Nozzle |
| title_fullStr | Enhancement of Film Cooling Effectiveness in a Supersonic Nozzle |
| title_full_unstemmed | Enhancement of Film Cooling Effectiveness in a Supersonic Nozzle |
| title_short | Enhancement of Film Cooling Effectiveness in a Supersonic Nozzle |
| title_sort | enhancement of film cooling effectiveness in a supersonic nozzle |
| topic | rocket nozzle cooling mixing layer studies diffuser-type coolant injector film cooling |
| url | https://www.mdpi.com/1099-4300/25/3/481 |
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