The expressions for the turbulent pressure, equation of state and thermodynamic quantities taking account of turbulent pressure are derived in the framework of the mixing-length theory of convection. The numerical computations indicate that the turbulent pressure in the region close to the surface of a red giant or anAGB star can reach a value of 30-40 percent of the total pressure. A compariso...

A mechanism for turbulent acceleration of parallel rotation is discovered using gyrokinetic theory. This new turbulent acceleration term cannot be written as a divergence of parallel Reynolds stress. Therefore, turbulent acceleration acts as a local source or sink of parallel rotation. The physics of turbulent acceleration is intrinsically different from the Reynolds stress. For symmetry breaki...

Relatively little systematic research has been conducted on the turbulence characteristics of small estuaries. In the present study, detailed measurements were conducted in a small subtropical estuary with a focus on turbulent flux events. Acoustic Doppler velocimeters were installed in the mid-estuary at fixed locations and sampled simultaneously and continuously for 50 h. A turbulent flux eve...

Gas control in coalmine was the critical issue since gas accidents give rise to a lot of harm. This paper put forward the optimization control strategy based on the turbulent mass transfer mechanism on the basis of previous research. First of all, gas turbulent mass transfer mathematical model was established in heading laneway. Three aspects were describing in detail, gas diffusion law and qua...

the design and optimization of hydrocyclones using cfd techniques are gaining popularity and the key to a successful simulation lies with the accurate description of the high turbulent swirling behavior of the flow. this paper presents a detailed comparison between the omega rsm and the rng k–e turbulence model, which are both derived specially for modeling swirling or rotational flow, in the s...

The airflow in the modeled glottal constriction was simulated by the solutions of the Navier-Stokes equations for laminar flow, and the corresponding Reynolds equations for turbulent flow in generalized, nonorthogonal coordinates using a numerical method. A two-dimensional model of laryngeal flow is considered and aerodynamic properties are calculated for both laminar and turbulent steady flows...

We determine the nonlinear drift velocities of the mean magnetic field and nonlinear turbulent magnetic diffusion in a turbulent convection. We show that the nonlinear drift velocities are caused by the three kinds of the inhomogeneities, i.e., inhomogeneous turbulence; the nonuniform fluid density and the nonuniform turbulent heat flux. The inhomogeneous turbulence results in the well-known tu...

one of the popular and well known models in boundary layer that is implemented in most of the operational and familiar models is the mellor-yamada model of atmospheric boundary layer. one reason that this model is so popular is its ability in simulations and exposing of different phenomena in the boundary layer. this model has been constructed based on second order closure hypothesis. beside al...

Laser Doppler Velocimetry (LDV) has been employed to determine pseudo-turbulence characteristics of the flow field around bubble train forming in non-Newtonian caboxymethylcellulose (CMC) aqueous solution at low gas flow rate condition. The Reynolds stress and turbulent intensity of the liquid were investigated by means of Reynolds time-averaged method. The experimental results show that ax...

In this paper, an enhancement design of communication system using optical radio frequency (RF) waves in free space optical communication (FSO) system is presented. To our knowledge, it is the first time that the effect of Gamma-Gamma turbulent channel model on the performance of the proposed system is analyzed and simulated. To obtain an optical communication system with good performance and h...