Journal of Applied Mechanical Engineering

Developing large-Eddy simulation of turbulent dispersed two-phase flows and combustion

3^rd International Conference on Fluid Dynamics & Aerodynamics

October 25-26, 2018 | Berlin, Germany

Lixing Zhou

Tsinghua University, China

Posters & Accepted Abstracts: J Appl Mech Eng

Abstract:

Statement of the Problem: Large-eddy simulation (LES) of turbulent dispersed two-phase flows and combustion attracts more and more attention, since it can give unsteady detailed flow and flame structures, which is important for understanding the processes, for example, in rocket, ramjet and internal combustion engines, and obtain more accurate statistical results than those obtained by Reynolds averaged Navier-Stokes (RANS) modeling. In doing LES the key problems are sub-grid scale (SGS) stress model and combustion model. Findings: The present author proposed SGS two-phase stress models for two-fluid LES and a second-order moment (SOM) SGS combustion model, and did the LES of turbulent gas-particle/droplet flows, turbulent gas premixed and un-premixed combustion and two-phase combustion. The statistical results are well validated by experiments. The instantaneous results reveal the detailed flow and flame structures for different cases, including coherent structures, and wrinkled and non-wrinkled flame structures. Conclusion & Significance: These studies indicate that the proposed SGS stress and combustion models are more accurate and economic. The LES results indeed show detailed flow and flame structures. These research results are helpful for developing and improving the CFD simulation of practical fluid and combustion facilities with high efficiency, low pressure loss and low pollutant emission.

Biography :

E-mail: zhoulx@mail.tsinghua.edu.cn