Combined experimental and numerical study on fuel deposition characteristics of an impinging PFI spray with different impingement geometries

Abstract

This paper presents a combined experimental and numerical study on the fuel deposition characteristics during the Port fuel injection (PFI) spray impingement process. The numerical models mainly consisted of a newly developed atomization model, the Senda spray impingement model, and the Bai-Gosman liquid film model. A group of measurement methods were used to hierarchically calibrate and validate the numerical models. It was found that the calibrated models were able to predict the time-resolved morphology of the impinging spray, as well as the shape, area, and thickness distribution of the deposited fuel film with a good reliability. Then the calibrated models were used to study the effects of impingement distance ( Lw) and impingement angle ( θw) on the fuel film deposition. The results showed that as Lw increases, the film area ( Af) and film mass ( mf) rise faster and reach higher final values. As θw increases, Af and mf grow slower, and their final values are hugely reduced. Increasing Lw and decreasing θw can effectively reduce the average film thickness ( hf,a). Af is mainly affected by the contact area between the spray plumes and the impinging wall, while mf is also affected by the dominant droplet-wall interaction regime.