Shear Flows in the Near-Turbulent Wake Region of High Speed Trains

Overview of turbulent shear flows

A brief review of basic concepts and folklore in shear turbulence. 1 Reynolds decomposition Experimental measurements show that turbulent flows can be decomposed into welldefined averages plus fluctuations, v = v̄ + v′. This is nicely illustrated in the Turbulence film available online at http://web.mit.edu/hml/ncfmf.html that was already mentioned in Lecture 1. In experiments, the average v̄ is ...

Study on Braking Panels in High Speed Trains Using CFD

With speed increasing in high-speed trains, due to limitations of other types of brakes, aerodynamic brake has become an important braking method. In this task to make better use of brake’s panel different configurations are examined and the best panel shape which provides the reasonable drag coefficient is introduced. The results of simulations are carried out with the computational fluid dyna...

Pdf Methods for Combustion in High-speed Turbulent Flows

Comparison of Turbulent Particle Dispersion Models in Turbulent Shear Flows

This work compares the performance of two Lagrangian turbulent particle dispersion models: the standard model (e.g., that presented in Sommerfeld et al. (1993)), in which the fluctuating fluid velocity experienced by the particle is composed of two components, one correlated with the previous time step and a second one randomly sampled from a Wiener process, and the model proposed by Minier and...

Polymer stress tensor in turbulent shear flows.

The interaction of polymers with turbulent shear flows is examined. We focus on the structure of the elastic stress tensor, which is proportional to the polymer conformation tensor. We examine this object in turbulent flows of increasing complexity. First is isotropic turbulence, then anisotropic (but homogenous) shear turbulence, and finally wall bounded turbulence. The main result of this pap...