GDI spray wall impingement against a heated and instrumented wall

Abstract

Spray–wall interaction (SWI) is critical in the atomization, mixing, and combustion behavior of fuels and the formation of pollutant emissions. These elusive effects impact internal combustion engine performance and other engineering applications such as spray-induced cooling, painting, and solid deposit control. As a result, spray wall interactions are an active area of research. This article aims to use a thermoregulated steel wall to study the spray–wall interaction phenomenon. A multi-hole injector manufactured by Continental was used. Isooctane was employed as the injected fuel, and the wall was positioned at one distance from the injector tip and one inclination angle, changing the wall surface temperature, the injection pressure, the ambient back pressure, the ambient temperature, and the fuel temperature. The spray–wall heat transfer is analyzed, and the heat flux is measured by employing high-speed thermocouples fitted in the wall and using a one-dimensional transient wall heat model. The ambient and wall temperatures highly affect the amount of liquid in the spray. By increasing both temperatures, a lesser amount of liquid was found. For the range evaluated in the experimental campaign, the results revealed a significant increase in surface heat flow and wall temperature variance with both wall and fuel temperatures and the ambient temperature, but to a lesser extent.