Quantitative Analysis of Fuel Film Formation and Evolution Following Spray Impingement China University of Mining and Technology, School of Low-Car

Format:

Book

Conference/Event

Author/Creator:

Qiu, Shuyi, author.

Contributor:

Li, Xuesong

Nour, Mohamed

Wang, Shangning

Xu, Min

Conference Name:

SAE 2024 Vehicle Powertrain Diversification Technology Forum (2024-12-06 : Xi'An, China)

Language:

English

Physical Description:

1 online resource cm

Place of Publication:

Warrendale, PA SAE International 2025

Summary:

Flash boiling spray has exhibited remarkable atomization performance by utilizing the sudden alterations in the thermodynamic state of the fluid during injection. The notable evaporation properties of flash boiling spray provide potential remedies for the problem of fuel film adhesion resulting from spray-wall impingement, especially during cold starts in reciprocating engines. Multi-hole injectors, which are often employed, frequently experience spray collapse under flash boiling conditions. The collapsing spray impinging a wall involves a complex multi-phase coupling mechanism. Once the spray impinges the wall, the heat and mass transfer between the wall and the adhering liquid film complicates the predictability of the fuel film characteristics. The quantitative evaluation of fuel film is crucial for studies on wall impingement. Nonetheless, the quantitative measurement of phase change fuel films necessitates addressing multiple problems, including evaporation and vapor phase interference. This work utilizes Mie scattering photography and Laser-Induced Exciplex Fluorescence (LIEF) techniques to examine the multi-plume spray impingement process. The impacts of the flash boiling superheat index and wall temperature were examined, alongside a quantitative analysis of the evolutions in the thickness, area, mass, and temperature of the adherent fuel film. The study results indicate that the spray collapses at a low superheat index. High fuel temperature diminishes liquid volume flux, hence reducing the mass of droplet impinging on the wall. The mass of the deposited fuel film reduces with an increase in fuel temperature, but low plate temperatures hinder evaporation and increase the mass of fuel film. The interplay of impinging droplets and evaporation governs fuel film's thickness and temperature. Under flare flash boiling conditions, even with a plate temperature of -25°C, the adhered film comprising merely 4% of the total injected fuel

Notes:

Vendor supplied data

Publisher Number:

2025-01-7045

Access Restriction:

Restricted for use by site license