Air separators provide safe, clean, and appropriate air flow to engines and are widely used in vehicles with large engines such as ships and submarines. In this operational study, the separation process in a Ranque-Hi...Air separators provide safe, clean, and appropriate air flow to engines and are widely used in vehicles with large engines such as ships and submarines. In this operational study, the separation process in a Ranque-Hilsch vortex tube cleaning （cooling） system is investigated to analyze the impact of the operating gas type on the vortex tube performance; the operating gases used are air, nitrogen, oxygen, carbon dioxide and nitrogen dioxide. The computational fluid dynamic model used is equipped with a three-dimensional structure, and the steady-state condition is applied during computations. The standard k-c turbulence model is employed to resolve nonlinear flow equations, and various key parameters, such as hot and cold exhaust thermal drops, and power separation rates, are described numerically. The results show that nitrogen dioxide creates the greatest separation power out of all gases tested, and the numerical results are validated by good agreement with available experimental data. In addition, a comparison is made between the use of two different boundary conditions, the pressure-far-field and the pressure-outlet, when analyzing complex turbulent flows in the air separators. Results present a comprehensive and practical solution for use in future numerical studies.展开更多
A detailed parametric study is conducted on three-dimensional gas-solid multiphase flow characteristics in inertial separators via numerical simulation. The carrier phase is treated in the Eulerian frame, the particle...A detailed parametric study is conducted on three-dimensional gas-solid multiphase flow characteristics in inertial separators via numerical simulation. The carrier phase is treated in the Eulerian frame, the particles are tracked in the Lagrangian frame, and particle-wall collision and particle-particle collision are considered. The inertial separators are made out of U-beam tube, arranged staggered .The separator has good performance for large particles and its compact structures make it easy to manufacture and install. The simulation is carried out in different inflow rate and provide the pressure losses in the separators, velocity field of gas phase, the trajectories of particles and the separation efficiency of separators. The result from this study not only shows the multiphase flow-dynamic characteristics of the separators, but also gives the relationship among the efficiency, structure and pressure losses of the separator. The comparison between the numerical simulation result and experimental data demonstrate the reliability of the numerical simulation.展开更多
文摘Air separators provide safe, clean, and appropriate air flow to engines and are widely used in vehicles with large engines such as ships and submarines. In this operational study, the separation process in a Ranque-Hilsch vortex tube cleaning （cooling） system is investigated to analyze the impact of the operating gas type on the vortex tube performance; the operating gases used are air, nitrogen, oxygen, carbon dioxide and nitrogen dioxide. The computational fluid dynamic model used is equipped with a three-dimensional structure, and the steady-state condition is applied during computations. The standard k-c turbulence model is employed to resolve nonlinear flow equations, and various key parameters, such as hot and cold exhaust thermal drops, and power separation rates, are described numerically. The results show that nitrogen dioxide creates the greatest separation power out of all gases tested, and the numerical results are validated by good agreement with available experimental data. In addition, a comparison is made between the use of two different boundary conditions, the pressure-far-field and the pressure-outlet, when analyzing complex turbulent flows in the air separators. Results present a comprehensive and practical solution for use in future numerical studies.
文摘A detailed parametric study is conducted on three-dimensional gas-solid multiphase flow characteristics in inertial separators via numerical simulation. The carrier phase is treated in the Eulerian frame, the particles are tracked in the Lagrangian frame, and particle-wall collision and particle-particle collision are considered. The inertial separators are made out of U-beam tube, arranged staggered .The separator has good performance for large particles and its compact structures make it easy to manufacture and install. The simulation is carried out in different inflow rate and provide the pressure losses in the separators, velocity field of gas phase, the trajectories of particles and the separation efficiency of separators. The result from this study not only shows the multiphase flow-dynamic characteristics of the separators, but also gives the relationship among the efficiency, structure and pressure losses of the separator. The comparison between the numerical simulation result and experimental data demonstrate the reliability of the numerical simulation.
