We investigate the velocity relaxation of a viscous one-dimensional granular gas in which neither energy nor momentum is conserved in a collision. Of interest is the distribution of velocities in the gas as it cools, and the time dependence of the relaxation behavior. A Boltzmann equation of instantaneous binary collisions leads to a two-peaked distribution, as do numerical simulations of grain...

We derive an analytic expression for the distribution of velocities of multiple interacting active particles which we test by numerical simulations. In clear contrast with equilibrium we find that the velocities are coupled to positions. Our model shows that, even for two particles only, the individual velocities display a variance depending on the interparticle separation and the emergence of ...

We present numerical studies of the properties of the stellar velocity distribution in galactic disks which have developed a saturated, two-armed spiral structure. In previous papers we used the Boltzmann moment equations (BME) up to second order for our studies of the velocity structure in self-gravitating stellar disks. A key assumption of our BME approach is the zero-heat flux approximation,...

The flow velocity distribution in partially-filled circular pipe was investigated in this paper. The velocity profile is different from full-filled pipe flow, since the flow is driven by gravity, not by pressure. The research findings show that the position of maximum flow is below the water surface, and varies with the water depth. In the region of near tube wall, the fluid velocity is mainly ...

A three-dimensional computational fluid dynamics (CFD) model was used to calculate the velocity distribution among multiple parallel microchannels with triangle manifolds. The influences of structural parameters on velocity distribution among microchannels were analyzed. The simulation results showed that the velocity distribution became more uniform with larger microchannel length, depth or sm...

We investigate the transverse velocity distribution of young (< 3 Myr) radio pulsars, using pulsar population synthesis techniques. We find that, after taking into account errors in proper motion measurements, an initial velocity distribution that has many more pulsars at low velocities than the distribution proposed by Lyne & Lorimer (1994) can produce a transverse velocity distribution that d...

Subcooled flow boiling in multi-microchannels can be used as an efficient thermal management approach in compact electrical devices. Highly subcooled flow boiling of HFE 7100 is studied in two microchannel heat sinks to choose a proper numerical model for simulating boiling flows in microchannels. Results of five different numerical models, including Volume of Fluid (VOF), Eulerian boiling, Eul...

Designing and manufacturing the multiple jets simulator and experimental investigation of the multiple jets in crossflow at low velocity ratios have been studied Together with design and build a low-speed wind tunnel. A specific rake is used to determine the flow field pressure and changes in static pressure measured by pressure taps in the near field of the jets. There are generally three regi...

mhd boundary layer flow of two phase model nanofluid over a vertical plate is investigated both analytically and numerically. a system of governing nonlinear partial differential equations is converted into a set of nonlinear ordinary differential equations by suitable similarity transformations and then solved analytically using homotopy analysis method and numerically by the fourth order rung...