TY - JOUR
T1 - Large eddy simulation of film cooling flow from shaped holes with different geometrical parameters
AU - Zamiri, Ali
AU - Barigozzi, Giovanna
AU - Chung, Jin Taek
N1 - Funding Information:
This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education ( 2020R1I1A1A01060578 ).
Publisher Copyright:
© 2022 Elsevier Ltd
PY - 2022/11/1
Y1 - 2022/11/1
N2 - Film-cooling approach is widely used in advanced gas turbines to protect the turbine components from the hot mainstream flow. The geometry of the cooling holes plays an important role in film cooling performance. In the current study, a large eddy simulation (LES) approach was performed to investigate the effects of various geometrical parameters of shaped cooling holes on the film-cooling effectiveness and turbulent flow characteristics. The reference cooling hole was located on a flat plate with a 35-degree injection angle at a constant density ratio of 1.5. The film-cooling effectiveness calculated by the LES approach was validated compared to that of the experimental data measured by PSP technique at different blowing ratios of M= 1.0, 1.5, and 2.0. Four important geometrical parameters, injection angle, metering length, forward expansion angle, and lateral expansion angle, were considered as design variables, and six different cases were designed and compared with the reference cooling hole. The computational data revealed that the cooling hole geometrical parameters significantly influence film-cooling performance. The designed shaped cooling hole showed an improvement in cooling performance of about 32% for the best case, compared to the reference case. In addition, the time/space analysis of the flow-field inside the cooling hole showed greater velocity fluctuations and more flow unsteadiness for the cooling holes with larger area ratios.
AB - Film-cooling approach is widely used in advanced gas turbines to protect the turbine components from the hot mainstream flow. The geometry of the cooling holes plays an important role in film cooling performance. In the current study, a large eddy simulation (LES) approach was performed to investigate the effects of various geometrical parameters of shaped cooling holes on the film-cooling effectiveness and turbulent flow characteristics. The reference cooling hole was located on a flat plate with a 35-degree injection angle at a constant density ratio of 1.5. The film-cooling effectiveness calculated by the LES approach was validated compared to that of the experimental data measured by PSP technique at different blowing ratios of M= 1.0, 1.5, and 2.0. Four important geometrical parameters, injection angle, metering length, forward expansion angle, and lateral expansion angle, were considered as design variables, and six different cases were designed and compared with the reference cooling hole. The computational data revealed that the cooling hole geometrical parameters significantly influence film-cooling performance. The designed shaped cooling hole showed an improvement in cooling performance of about 32% for the best case, compared to the reference case. In addition, the time/space analysis of the flow-field inside the cooling hole showed greater velocity fluctuations and more flow unsteadiness for the cooling holes with larger area ratios.
KW - Fan-shaped cooling hole
KW - Film-cooling
KW - Large eddy simulation
UR - http://www.scopus.com/inward/record.url?scp=85134978899&partnerID=8YFLogxK
U2 - 10.1016/j.ijheatmasstransfer.2022.123261
DO - 10.1016/j.ijheatmasstransfer.2022.123261
M3 - Article
AN - SCOPUS:85134978899
SN - 0017-9310
VL - 196
JO - International Journal of Heat and Mass Transfer
JF - International Journal of Heat and Mass Transfer
M1 - 123261
ER -