Experimental Investigation on Thermal Protection of High Temperature and High Velocity Jet Impinging a Cross-Shaped plate

Abstract

This paper investigated the heat transfer of high temperature jet impinging a cross-shaped plate. An experimental mockup was designed and used to produce high temperature (∼500 °C) impinging gas jet with stable high speed (∼56 m/s) at the nozzle exit. A one-dimensional theoretical model was proposed to predict the temperature increment of the back-side surface(s) that opposed to the impinging surface, by simplifying and assuming the heat transfer process can be governed by convection. Three materials were selected due to its potential high heat transfer resistance, speedy installation and long duration under severe impinging conditions. For each material, four types of thermal insulation structures were designed and subjected for testing. The following conclusions from comparison of the results of the model predictions with experimental data can be drawn. The proposed simplified one-dimensional model can be used to predict heat transfer at the back-side under high temperature and high-speed impinging. The optimal case among the 12 thermal protecting designs was obtained, majorly due to low back temperature and less material consumption.

Acknowledgments

The authors would like to thank Mr. Jingtao Huo and Miss Wenxuan Zhao at Tongji University for their assistance in conducting the experiments.

Notes on contributors

Jian Cai is a Ph.D. candidate majoring in the heat transfer of impinging jet at Tongji University. He received his master’s degree in power engineering from Tongji University in 2012. And now he is also an engineer at a laboratory center in Tongji University.

Wei Ye, Assistant Professor, received his Ph.D. from Tongji University in 2014. He has authored or coauthored more than 60 journal papers in both English and Chinese. His current research interests are indoor air quality and ventilation.

Shuyang Tu received his master’s degree in HVAC from Tongji University in 2018. He was rewarded several times in HVAC design competitions. He has authored or coauthored nine academic papers, including one SCI paper and two EI papers.

Shaochen Tian received his bachelor’s degree in HVAC from Tongji University in 2017. He is now a graduate student, majoring in rotary dehumidification technology.

Xu Zhang, Professor, received his Ph.D. from Tongji University in 1997 and has been actively involved in teaching and research on heating, ventilation and air conditioning (HVAC) for more than 30 years. He is the director of the Institute of HVAC Engineering at Tongji University. He has been appointed as the Director of the Sub-committee of Air Conditioning of China Committee of Heating, Ventilation & Air-conditioning (CCHVAC), and General Secretary and Vice Chairman of Shanghai Society of Refrigeration (SSR).

Additional information

Funding

This research has been supported by the National Natural Science Foundation of China under Grant No. 51878463.