Similar Characteristics of Heat Transfer in Different Scale Cooling Channel with Ribs

Abstract

The gas turbines are highly demanded in modern industries, and the improvement of the performance derives from the increase of the turbine inlet temperature. Various cooling structures are used, such as ribs, pin fins, to improve heat transfer performance and extend the lifespan of the blade. Due to the limitations of the measurement technique, magnified geometry models have been tested with similarity theory in the past. In this paper, a thermochromic liquid crystal experiment was conducted to investigate the heat transfer performance of a magnified rectangular channel with ribs, supplemented with numerical simulation. The results indicated that the vortex and secondary flow generated by the ribs enhance the local heat transfer. Moreover, the thermal performance of the rib-roughed rectangular cooling channel was calculated under different scale factor conditions. The quantitative correlation equations of Nusselt number and friction coefficient versus the scale factor were established. Nusselt number showed an exponential growth with the increase of scale factor, while the friction coefficient displayed an exponential decay. Compared with the baseline, the enhanced heat transfer coefficient is improved by 18.7% and the normalized friction coefficient is dropped by 8.2% with geometry scaled up 10 times.

Additional information

Funding

This work is supported by National Science and Technology Major Project under Grant [2017-V-0012-0064]; National Natural Science Foundation of China (NSFC) under Grant [No. 51509052].

Notes on contributors

Zhongyi Wang

Zhongyi Wang is working at the College of Power and Energy Engineering of HRBEU as a Professor. He graduated from Harbin Engineering University in June 2010 with a Ph.D. degree in Marine Engineering. His research is on performance study of intake and exhaust systems in ship power plant, and the compressor performance prediction.

Yue Yin

Yue Yin is a Ph.D. student studying at the College of Power and Energy Engineering of Harbin Engineering University. He graduated from Harbin Engineering University in June 2018 with a Bachelor's degree in Energy and Power Engineering. At present, his research is on the performance study of turbine blades internal cooling with numerical simulation and experimental methods.

Lianfeng Yang

Lianfeng Yang is a Ph.D. student from the University of Genoa. He graduated from Harbin Engineering University in March 2018 with a master degree in Marine Engineering. He carries out his research on the turbine blades internal and external cooling technology with numerical simulation and experimental methods.

Yanhua Wang

Yanhua Wang is working at the college of Power and Energy Engineering of Harbin Engineering University. He graduated from Northwestern Polytechnical University in June 2018 with a Ph.D. degree in Aerospace Science and Technology. His research is on vitiation species effects on supersonic combustor blowout limit and vitiation species effects on flame spreading characteristic.

Yigang Luan

Yigang Luan is working at the college of Power and Energy Engineering of HRBEU as a Professor. He graduated from Harbin Engineering University in June 2011 with a Ph.D. degree in Marine Engineering. His research is on performance study of intake and exhaust systems in ship power plant, and turbine blades cooling technology.