Yuxin Wu1, Philip J. Smith2, Jeremy N. Thornock2, Guangxi Yue1, and Jiansheng Zhang1. (1) Thermal Engineering, Tsinghua University, Beijing, 100084, China, (2) University of Utah, 155 S. 1452 E. Rm 380, Salt Lake City, UT 84112
The One Dimensional Turbulence (ODT) model was used to study a particle laden flow in a planar jet. As An outgrowth of the LEM (Linear Eddy Model) model, the ODT model maintains a distinction among the turbulence, molecular diffusion and chemical reaction scales. Additionally, the turbulent mixing process is only considered in one-dimension, where eddy events are stochastically represented, which allows for representation of a large range of time and length scales with relatively small computing requirements. In this study, the particle and fluid time scales are split by advancing the fluid phase independently of the particle phase. When an eddy was judged to occur, it is assumed that the eddy will always exist at this place, therefore locations of the eddy occurrences in the fluid phase are recorded after each fluid advancement step. After the fluid phase has advanced, particles are tracked through the established flow field, interacting with the eddy occurrences. When a particle encounters an eddy, its motion is affected by the eddy velocity, which is a combination of the local gas flow field and turbulent mixing. With this method, eddy effects on the particle motion are considered. The ODT model results of the planar jet show that particles cluster at the mixing layer where eddy events are more likely to occur. This result suggests that turbulent eddies have an important effect on particle dispersion. Also, we show that particle diameter has a negative effect on particle dispersion, causing large particles to concentrate at center of the jet while small particles disperse to the edge. The ability of this ODT model to capture these dispersion effects provides motivation for applying it to particle-gas chemical processes, such as coal combustion and gasification where particle clustering and dispersion has been observed.