Modeling the Effects of Drop Impingement Frequency on Heated Walls at Engine Conditions
2022-01-0592
03/29/2022
- Event
- Content
- Understanding the fundamental details of drop/wall interactions is important to improving engine performance. Most of the drop-wall interactions studies are based on the impact of a single drop on the wall. To accurately mimic and model the real engine conditions, it is necessary to characterize spray/wall interactions with different impingement frequencies at a wide range of wall temperatures. In this study, a numerical method, based on Smoothed Particle Hydrodynamics (SPH), is used to simulate consecutive droplet impacts on a heated wall both below and above Leidenfrost temperature. Impact regimes are identified for various impact conditions by analyzing the time evolution of the post-impingement process of n-heptane drops at different impingement frequencies and wall surface temperatures. At low temperature, crown propagation and merging are dominant at low K-number whereas at high K-number there is significant splashing with the traces of liquid film on the surface. Around and above Leidenfrost temperature, drop rebound is seen and the succeeding drop interacts with the rebounding drop and merges at low K-number whereas film splashing is observed at high K-number with secondary droplets interacting and merging with the incoming drops. This study will further lead to the development of spray/wall impingement models at realistic engine conditions.
- Citation
- Subedi, K., and Kong, S., "Modeling the Effects of Drop Impingement Frequency on Heated Walls at Engine Conditions," SAE Technical Paper 2022-01-0592, 2022, .