Design and Combustion Characteristic Analysis of Free Piston Stirling Engine External Combustion System

doi:10.1007/s12204-018-2022-x

Abstract

Abstract: The free piston Stirling engine external combustion system was simulated to investigate the diesel-air combustion characteristics in order to demonstrate its feasibility by computational fluid dynamics (CFD). The different effects on combustion were distinguished by analyzing the combustion burner, the injection position of diesel oil, the front tube arrangement of Stirling heater head and the back fin. The results show that the tilted front tube arrangement of the heater head with the back fin is the best practicable technology while the distance between the diesel nozzle position and the swirler top is 0. Its total heat flux is 15.6 kW, and the average heat transfer coefficients of the front and back tubes are 127W/(m2 ·K) and 192W/(m2 ·K), respectively. The heat transfer is mainly through convection, and the proportion of radiative heat transfer is only 16.9%. The best combustion efficiency of the free piston Stirling engine external combustion system is 86%.

Key words: Stirling engine| external combustion system| numerical simulation| diesel-air combustion

摘要： The free piston Stirling engine external combustion system was simulated to investigate the diesel-air combustion characteristics in order to demonstrate its feasibility by computational fluid dynamics (CFD). The different effects on combustion were distinguished by analyzing the combustion burner, the injection position of diesel oil, the front tube arrangement of Stirling heater head and the back fin. The results show that the tilted front tube arrangement of the heater head with the back fin is the best practicable technology while the distance between the diesel nozzle position and the swirler top is 0. Its total heat flux is 15.6 kW, and the average heat transfer coefficients of the front and back tubes are 127W/(m2 ·K) and 192W/(m2 ·K), respectively. The heat transfer is mainly through convection, and the proportion of radiative heat transfer is only 16.9%. The best combustion efficiency of the free piston Stirling engine external combustion system is 86%.

关键词: Stirling engine| external combustion system| numerical simulation| diesel-air combustion

CLC Number:

TK 16

JIN Xudong (金旭东), Lü Tian (吕田), YU Guoyao (余国瑶), LIU Jiawei (刘佳伟), HUANG Xiaoyu (黄晓宇). Design and Combustion Characteristic Analysis of Free Piston Stirling Engine External Combustion System[J]. Journal of Shanghai Jiao Tong University (Science), 2018, 23(Sup. 1): 50-55.

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