汽油直喷高压喷雾在非闪沸与闪沸条件下的特性研究

J Shanghai Jiaotong Univ Sci››2024,Vol. 29››Issue (2): 230-236.doi:10.1007/s12204-022-2480-z

汽油直喷高压喷雾在非闪沸与闪沸条件下的特性研究

王森，徐宏昌，李雪松，袁志远

（开云网页登录机械与动力工程学院汽车电子与控制技术国家工程实验室，上海 200240）

接受日期:2021-06-11出版日期:2024-03-28发布日期:2024-03-26

Characteristics of High-Pressure Spray of a Gasoline Direct Injection Injector Under Non-Flash Boiling and Flash Boiling Conditions

WANG Sen (王森), XU Hongchang (徐宏昌), LI Xuesong (李雪松), YUAN Zhiyuan^∗（袁志远）

(National Engineering Laboratory for Automotive Electronic Control Technology, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China)

Accepted:2021-06-11Online:2024-03-28Published:2024-03-26

摘要/Abstract

摘要：日趋严格的排放法规和燃油消耗要求对内燃机燃油效率和更低排放提出了更高的需求。大量研究表明，闪急沸腾雾化可以产生更短、更宽的喷雾，具有改善雾化和蒸发的特性，促进更好的空燃混合过程。本研究在非闪沸和闪沸条件下，对两孔汽油直喷喷油器的宏观（远场）喷雾形态和初级破碎（近场）特性进行了研究。研究采用高速宏观和显微成像技术分别捕捉整体喷雾结构和近场特性，采用正己烷作为测试燃料，喷射压力范围从10 MPa到40 MPa。对于冷态液体燃料喷雾，增加燃油压力有助于提高燃油雾化和蒸发；而在闪沸条件下明显发生坍塌，而较高的喷射压力因喷射速度增加，导致喷雾锥角减小，抑制了这一现象发生。

关键词:闪急沸腾雾化，高压喷射，内燃机，光学诊断

Abstract:The increasingly stringent emission regulations and fuel consumption requirements have elevated the demands of internal combustion engines with higher fuel efficiency and lower emissions. It has been widely demonstrated that flash boiling spray can generate shorter and wider spray with improved atomization and evaporation to promote a better air-fuel mixing process. In this study, macroscopic (far-field) spray morphologies and primary breakup (near-field) characteristics of a two-hole gasoline direct injection injector are investigated under non-flash boiling and flash boiling conditions. High speed macroscopic and microscopic imaging was used to capture the overall spray structure and near-field characteristics, respectively. N-Hexane is used as the test fuel with the injection pressure ranging from 10 MPa up to 40 MPa. For sub-cooled liquid fuel sprays, increasing fuel pressure contributes to enhanced fuel atomization and evaporation. Evident collapses occurred under flare flash boiling conditions, and higher injection pressure weakened this phenomenon since the spray cone angle decreased due to a higher injection velocity.

Key words:flash boiling atomization, high-pressure injection, internal combustion engines, optical diagnostics

中图分类号:

TK11

王森，徐宏昌，李雪松，袁志远. 汽油直喷高压喷雾在非闪沸与闪沸条件下的特性研究[J]. J Shanghai Jiaotong Univ Sci, 2024, 29(2): 230-236.

WANG Sen (王森), XU Hongchang (徐宏昌), LI Xuesong (李雪松), YUAN Zhiyuan（袁志远）. Characteristics of High-Pressure Spray of a Gasoline Direct Injection Injector Under Non-Flash Boiling and Flash Boiling Conditions[J]. J Shanghai Jiaotong Univ Sci, 2024, 29(2): 230-236.

参考文献

[1] ZHAO F, LAI M C, HARRINGTON D L. Automotive spark-ignited direct-injection gasoline engines [J]. Progress in Energy and Combustion Science, 1999, 25(5): 437-562.
[2] HOFFMANN G, BEFRUI B, BERNDORFER A, et al. Fuel system pressure increase for enhanced performance of GDi multi-hole injection systems [J]. SAE International Journal of Engines, 2014, 7(1): 519-527.
[3] PIOCK W F, BEFRUI B, BERNDORFER A, et al. Fuel pressure and charge motion effects on GDi engine particulate emissions [J]. SAE International Journal of Engines, 2015, 8(2): 464-473.
[4] HUSTED H, SPEGAR T D, SPAKOWSKI J. The effects of GDi fuel pressure on fuel economy [C]// SAE 2014 World Congress & Exhibition. Detroit, Michigan: SAE International, 2014: 2014-01-1438.
[5] YANG S Z, MA Z, LI X S, et al. A review on the experimental non-intrusive investigation of fuel injector phase changing flow [J]. Fuel, 2020, 259: 116188.
[6] LI X S, YANG S Z, LI T Y, et al. Investigations on near-field atomization of flash boiling sprays for gasoline direct injection related applications [J]. Fuel, 2019, 257: 116097.
[7] HWANG J, PARK Y, BAE C, et al. Fuel temperature influence on spray and combustion characteristics in a constant volume combustion chamber (CVCC) under simulated engine operating conditions [J]. Fuel, 2015, 160: 424-433.
[8] YANG S Z, LI X S, HUNG D L S, et al. In-nozzle flash boiling flow of multi-component fuel and its effect on near-nozzle spray [J]. Fuel, 2019, 252: 55-67.
[9] MOJTABI M, CHADWICK N, WIGLEY G, et al. The effect of flash boiling on breakup and atomisation in GDI sprays [C]//22nd European Conference on Liquid Atomization and Spray Systems. Como Lake: ILASS Europe, 2008: ILASS08-6-1.
[10] YANG S Z, LI X S, HUNG D L S, et al. Effect of injection pressure on nozzle internal flow and jet breakup under sub-cooled and flash boiling test conditions [J]. SAE Technical Paper, 2019: 2019-01-0286.
[11] XIAO D, QIU S Y, HUNG D, et al. Evaporation and condensation of flash boiling sprays impinging on a cold surface [J]. Fuel, 2021, 287: 119423.
[12] HE X, LI Y K, LIU C, et al. Characteristics of spray and wall wetting under flash-boiling and non-flashing conditions at varying ambient pressures [J]. Fuel, 2020, 264: 116683.
[13] CHAN Q N, BAO Y M, KOOK S. Effects of injection pressure on the structural transformation of flash-boiling sprays of gasoline and ethanol in a sparkignition direct-injection (SIDI) engine [J]. Fuel, 2014, 130: 228-240.
[14] PAYRI R, SALVADOR F J, MART′I-ALDARAV′I P, et al. ECN Spray G external spray visualization and spray collapse description through penetration and morphology analysis [J]. Applied Thermal Engineering, 2017, 112: 304-316.
[15] MONTANARO A, ALLOCCA L. Flash boiling evidences of a multi-hole GDI spray under engine conditions by Mie-scattering measurements [J]. SAE Technical Paper, 2015: 2015-01-1945.
[16] ZENG W, XU M, ZHANG M, et al. Macroscopic characteristics for direct-injection multi-hole sprays using dimensionless analysis [J]. Experimental Thermal and Fluid Science, 2012, 40: 81-92.
[17] ZHANG G M, HUNG D L S. Temporal investigations of transient fuel spray characteristics from a multi-hole injector using dimensionless analysis [J]. Experimental Thermal and Fluid Science, 2015, 66: 150-159.
[18] ZHANG M, XU M, HUNG D L S. Simultaneous twophase flow measurement of spray mixing process by means of high-speed two-color PIV [J]. Measurement Science and Technology, 2014, 25(9): 095204.