Abstract. Pumping performance of a disk-type drag pump is studied numerically and experimentally. Molecular transition and slip flows that arise in a spiral channel on the rotating disk are simulated by using particle and continuum methods. The particle approach employs the direct simulation Monte Carlo (DSMC) method, and the continuum approach solves the Navier-Stokes (N-S) equations. A new DS...

A modular particle-continuum (MPC) numerical method is presented which solves the Navier-Stokes (NS) equations in regions of near-equilibrium and uses the direct simulation Monte Carlo (DSMC) method where the flow is in non-equilibrium. The MPC method is designed specifically for steady-state, hypersonic, nonequilibrium flows and couples existing, state-of-the-art DSMC and NS solvers into a sin...

Through the laboratory experiments, the mechanical properties of sandy gravel are obtained. Then, based on the slump tests, a modified sandy gravel model is developed by PFC (particle flow code of three dimensions), to which relevant microscopic parameters are assigned to numerically simulate the laboratory experiments. The laboratory test results are compared with that of the numerical simulat...

An analysis of groundwater flow and transport processes of arsenic in the flow domain of the Yamuna sub-basin located in West Bengal (India) is presented. The objectives of the analysis are: to conceptualize the groundwater flow domain, to determine groundwater flow paths and groundwater velocities, to study arsenic transport in the flow domain, and to study the well captures zones. The first t...

The paper describes a particle-resolved simulation method for turbulent flow laden with finite size particles. The method is based on the multiple-relaxation-time lattice Boltzmann equation. The no-slip boundary condition on the moving particle boundaries is handled by a second-order interpolated bounce-back scheme. The populations at a newly converted fluid lattice node are constructed by the ...

A new Cartesian implementation of the direct simulation Monte Carlo (DSMC) method, named the hypersonic aerothermodynamics particle (HAP) code, is presented. This code is intended for rapid setup and simulation of rarefied flow problems, and as a framework for evaluating new physical models and numerical techniques. Unique features include the use of nonuniform Cartesian adaptive subcells, a co...