Numerical simulations are performed both for the single airflow and air-PMtwo-phase flow in wall flow diesel participate filters (DPF) for the first time. The calculationdomain is divided into two regions. In. the inl...Numerical simulations are performed both for the single airflow and air-PMtwo-phase flow in wall flow diesel participate filters (DPF) for the first time. The calculationdomain is divided into two regions. In. the inlet and outlet flow channels, the simulations areperformed for the steady and laminar flow; In the porous filtration walls, the calculation model forflow in porous media is used. The Lagrange two-phase flow model is used to calculate the air-PMflow in DPF, for the dispersed phase (PM), its flow tracks are obtained by the integrating of theLagrange kinetic equation. The calculated velocity, pressure distribution and PM flow tracks in DPFare obtained, which exhibits the main flow characteristics in wall flow DPF and will be help for theoptimal design and performance prediction of wall flow DPF.展开更多
Pumped storage power stations on sediment-laden rivers are highly susceptible to erosion damage on the surfaces of major flow-passingcomponents due to sediment particles.In this study,an Euler-Lagrange model is employ...Pumped storage power stations on sediment-laden rivers are highly susceptible to erosion damage on the surfaces of major flow-passingcomponents due to sediment particles.In this study,an Euler-Lagrange model is employed to numerically investigate the sand-water flowcharacteristics and erosion prediction of a pump-turbine under hump-region conditions,focusing on crest,trough,and high-flow operatingpoints.The results show that the internal flow of the pump-turbine undergoes significant changes in the hump region.Under low-flowconditions,flow separation,backflow,and local vortex phenomena occur inside the runner.Vortices in the runner passages tend to entrainsediment particles,resulting in a reduction in particle velocity.With increasing sand-water flow rate,a pronounced velocity difference developson both sides of the blades,with the maximum difference reaching 20 m/s.The average erosion rates on the runner blades and the endfaces of the guide vanes are 4.2×10^(-8) and 3.5×10^(-8) kg/(s·m^(2)),respectively.The cutting erosion patterns on the blade surfaces coincide withthe trajectories of the water flow vortices,and the erosion rate distribution on the guide vane end faces shows a high degree of consistencywith the distribution of sand-water vortices.展开更多
文摘Numerical simulations are performed both for the single airflow and air-PMtwo-phase flow in wall flow diesel participate filters (DPF) for the first time. The calculationdomain is divided into two regions. In. the inlet and outlet flow channels, the simulations areperformed for the steady and laminar flow; In the porous filtration walls, the calculation model forflow in porous media is used. The Lagrange two-phase flow model is used to calculate the air-PMflow in DPF, for the dispersed phase (PM), its flow tracks are obtained by the integrating of theLagrange kinetic equation. The calculated velocity, pressure distribution and PM flow tracks in DPFare obtained, which exhibits the main flow characteristics in wall flow DPF and will be help for theoptimal design and performance prediction of wall flow DPF.
文摘Pumped storage power stations on sediment-laden rivers are highly susceptible to erosion damage on the surfaces of major flow-passingcomponents due to sediment particles.In this study,an Euler-Lagrange model is employed to numerically investigate the sand-water flowcharacteristics and erosion prediction of a pump-turbine under hump-region conditions,focusing on crest,trough,and high-flow operatingpoints.The results show that the internal flow of the pump-turbine undergoes significant changes in the hump region.Under low-flowconditions,flow separation,backflow,and local vortex phenomena occur inside the runner.Vortices in the runner passages tend to entrainsediment particles,resulting in a reduction in particle velocity.With increasing sand-water flow rate,a pronounced velocity difference developson both sides of the blades,with the maximum difference reaching 20 m/s.The average erosion rates on the runner blades and the endfaces of the guide vanes are 4.2×10^(-8) and 3.5×10^(-8) kg/(s·m^(2)),respectively.The cutting erosion patterns on the blade surfaces coincide withthe trajectories of the water flow vortices,and the erosion rate distribution on the guide vane end faces shows a high degree of consistencywith the distribution of sand-water vortices.
