ARC Seminar: Arif Hossain

Arif Hossain

Graduate Research Associate, College of Engineering
The Ohio State University

Sweeping Jet Film Cooling for Gas Turbine Heat Transfer Application

Location: ARC 100
Light refreshments served after.

Arif Hossain
Arif Hossain is a final year Ph.D. candidate in the Department of Mechanical and Aerospace Engineering at The Ohio State University. He received his Bachelor’s degree in Mechanical engineering from Bangladesh University of Engineering and Technology (BUET) in 2012, and Master’s degree in Mechanical Engineering from the University of Texas at El Paso (UTEP) in 2015. He has more than five years of research experience in experimental and numerical fluidic mechanics and heat transfer. He has been working on the sweeping jet film cooling and impingement cooling for the last four years under the supervision of Professor Jeffrey Bons, Professor James Gregory, and Dr. Ali Ameri. He has received several prestigious ASME IGTI awards, including the IGTI student advisory award, IGTI Young Engineers Award, and ASME IGTI student scholarship award.

Abstract
Due to the increased freedom in additive manufacturing, the complex internal and external geometries of the turbine blade can be leveraged to utilize innovative cooling designs to address some of the shortcomings of current cooling technologies. The sweeping jet film cooling has shown some promise to be an effective method of cooling where the coolant can be brought very close to the blade surface due to its sweeping nature. A series of experiments were performed using a row of fluidic oscillators on a flat plate. Adiabatic cooling effectiveness, convective heat transfer coefficient, thermal field, and discharge coefficient were measured over a range of blowing ratios and freestream turbulence. Results were compared with a conventional shaped hole (777-hole), and the sweeping jet hole shows improved cooling performance in the lateral direction. Numerical simulation also confirmed that the sweeping jet creates two alternating vortices that do not have mutual interaction in time. When the jet sweeps to one side of the hole exit, it acts as a vortex generator as it interacts with the mainstream flow. This prevents the formation of the counter rotating vortex pair (CRVP) and allows the coolant to spread in the lateral direction. The results obtained from the low speed flat plate tests were utilized to design the sweeping jet film cooling hole for more representative turbine vane geometry. Experiments were performed in a low speed linear cascade and a high speed transonic cascade facility. Results showed that the sweeping jet hole has higher cooling effectiveness in the near hole region compared to the shaped hole at high blowing ratios. The systematic evolution of a sweeping jet film cooling hole design from a flat plate to a nozzle guide vane has been presented.  

Hosted by Dr. Jeffrey Bons, Department of Mechanical and Aerospace Engineering and Aerospace Research Center.