This paper discusses the capabilities of a two-fluid turbulence model for solving complex physical problems such as separated flow around square cylinder and laminar-turbulent in suddenly expanding channel. The numerical solution to system hydrodynamic equations is implemented using finite-difference scheme. At each time step, velocities are corrected through pressure calculations according SIM...

In this study we built a nano-CPC (condensation particle counter) battery, consisting of four ultrafine CPCs optimized for the detection of sub-3 nm particles. Two of the CPCs use diethylene glycol as a working fluid: a laminar type diethlylene glycol CPC and a mixing type Airmodus A09 particle size magnifier. The other two CPCs are a laminar type TSI 3025A and a TSI 3786 with butanol and water...

Direct numerical simulations are used to study the laminar to turbulent transition of a Mach 2.9 supersonic flat plate boundary layer flow due to distributed surface roughness. Roughness causes the near-wall fluid to slow down and generates a strong shear layer over the roughness elements. Examination of the mean wall pressure indicates that the roughness surface exerts an upward impulse on the...

Cardiovascular disease mostly in the form of atherosclerosis is responsible for 30% of all world deaths amounting to 17 million people per year. Atherosclerosis is due to the formation of plaque. The fatty plaque may be at risk of rupture, leading typically to stroke and heart attack. The plaque is usually associated with a high degree of lumen reduction, called a stenosis. The initiation and p...

Computational Fluid Dynamics (CFD) software simulates fluid, air flow and heat transfer by solving the Navier-Stokes (N-S) equations numerically. Realistic 3-D engineering simulations typically yield the values of 7 or more variables (e.g. fluid component velocities and temperatures) at hundreds of thousands of points in space, all as a function of time. It has been noted that solutions of the ...

The phenomenon of "unmixing" has been demonstrated in microfluidic mixers, but here we manipulate laminar flow streams back to their original positions in order to extend the operational utility of an analytical device where no mixing is desired. Using grooves in the channel wall, we passively focus a sample stream with two sheath streams to center it in a microchannel for optical analysis. Eve...

This article mainly concerns theoretical research on entropy generation influences due to heat transfer and flow in nanofluid suspensions. A conventional nanofluid of alumina-water (Al2O3-H2O) was considered as the fluid model. Due to the sensitivity of entropy to duct diameter, miniand microchannels with diameters of 3 mm and 0.05 mm were considered, and a laminar flow regime was assumed. The ...

This paper describes the heat and mass transfer in a square microchannel that is heated from one side. This microchannel represents a reaction channel in a microreactor that is used to study the kinetics of the catalytic partial oxidation of methane. The microchannel is contained in a silicon wafer and is covered by a thin silicon sheet. At the top side of this sheet, heating elements are prese...

The Unsteady laminar flow of an electrically conducting dusty viscous incompressible fluid near an accelerated flat, nonconducting plate, under the influence of a uniform magnetic field and pulsatile pressure gradient has been studied using differential geometry techniques i.e., in Frenet frame field system. The particular cases as (i) impulsively moving and (ii) uniformly accelerated motion of...