An Experimental and Numerical Study on the Cavitation and Spray Characteristics of Micro-Orifice Injectors under Low-Pressure Conditions

doi:10.3390/en17051045

淡江大學機構典藏 > 工學院 > 航空太空工程學系暨研究所 > 期刊論文 > Item 987654321/125144

Please use this identifier to cite or link to this item: https://tkuir.lib.tku.edu.tw/dspace/handle/987654321/125144

Title:	An Experimental and Numerical Study on the Cavitation and Spray Characteristics of Micro-Orifice Injectors under Low-Pressure Conditions
Authors:	Chen, Tzeng-Yuan;Yang, Chih-Cheng;Ouyang, Kwan
Keywords:	micro-orifice injector;cavitation;liquid jet;discharge coefficient
Date:	2024-02-22
Issue Date:	2024-03-06 12:05:15 (UTC+8)
Publisher:	MDPI AG
Abstract:	A fuel injector plays a crucial role in an internal combustion engine, and the occurrence of cavitation inside the injector may affect the engine’s spray characteristics, atomization characteristics, and combustion efficiency. Most literature investigated the cavitation characteristics for a micro-orifice injector under high injection pressure (P_inj) or a large-orifice injector under low P_inj, i.e., under high Reynolds number (Re). In this study, a micro-turbojet engine with a 0.3-mm-diameter micro-orifice fuel injector was developed for operation under low P_inj. The cavitation and spray characteristics of water and kerosene fuel in this injector were experimentally and numerically investigated. The results indicated that the water and kerosene also exhibited no cavitation, cavitation, super-cavitation, and hydraulic flip phenomena. However, the discharged jet was unaffected by the internal flows, and the jet angles remained approximately constant, implying that the cavitation in micro-orifice injectors under low Re is less important than that under high Re. Since the cavitation in micro-orifice injectors under low Re is not beneficial to the atomization and spray, the selection of geometry of the micro-injector is important. A micro-orifice injector with a small length-to-diameter (L/D) ratio of the injector nozzle has a rounded-edge inlet and a small taped angle due to the limitation of electrical discharge machining, which results in a high discharge coefficient and increases the difficulty of hydraulic flip. Thus, an L/D ratio of 3 is recommended for the injector of the developed micro-turbojet engine. This study provides some insights for the design of micro-turbojet engines.
Relation:	Energies 17(5), 1045
DOI:	10.3390/en17051045
Appears in Collections:	[航空太空工程學系暨研究所] 期刊論文

Files in This Item:

File	Description	Size	Format
index.html		0Kb	HTML	6	View/Open

Loading...