When condensation occurs in supersonic flow fields, the flow is thected by the latent heat released. In the present study, Navier-Stokes equations were solved numerically using a 3rd-order MUSCL type TVD finitediffere...When condensation occurs in supersonic flow fields, the flow is thected by the latent heat released. In the present study, Navier-Stokes equations were solved numerically using a 3rd-order MUSCL type TVD finitedifference scheme with a second-order fractionabetep for time integration. Baldwin-Lomax model, that is the algebraic model, called the zero equation model was used in the computations. The effects of initial conditions (initial degree of supersaturation and total temperature in the reservoir) on condensing fiow of moist air in a supersonic circular half nozzle were investigated. In this case, the effect of condensation on the boundary layer was also discussed in detail. As a result, the simulated flow fields were compared with experimental data in good agreement, and the velocity and temperature profiles were largely changed by condensation.展开更多
When condensation occurs in supersonic flow fields, the flow is affected by the latent heat released, and if the heat released exceeds a certain quantity, a condensation shock wave will occur There are many papers for...When condensation occurs in supersonic flow fields, the flow is affected by the latent heat released, and if the heat released exceeds a certain quantity, a condensation shock wave will occur There are many papers for the passive control of shock-boundary layer interaction using the porous wall with a plenum underneath on the application of the technique to transonic airfoil flows. In the present study, this passive technique is applied to the control of a steady condensation shock wave generated in a supersonic nozzle. In order to clarify the effect of the passive shockboundary layer control on condensation shock, Navier-Stokes equations were solved numerically using a 3rd-order MUSCL type TVD finite-difference scheme with a second-order fractional-step for time integration. As a result, the simulated flow fields were compared with experimental data in good agreement and the aspect of the flow field has been clarified.展开更多
The homogeneous nucleation with subsequent spontaneous condensation of water, pentanol, and ethanol xupors in a carrier gas are investigated experimentally and theoretically in the expansion part of a shock tube. The ...The homogeneous nucleation with subsequent spontaneous condensation of water, pentanol, and ethanol xupors in a carrier gas are investigated experimentally and theoretically in the expansion part of a shock tube. The precise pressure and Mcw measurements give additional information about the wetness, so that the nucleation and condensation rates which are closely coupled for stronger expansion rates are determined more accurately. Predictions of the principle of the minimum of entropy production are compared with experiments performed for water, ethanol and pentanol at different pressures.展开更多
A rapid expansion of moist air or steam in a supersonic nozzle gives rise to nonequilibrium condensation phenomena. Thereby, if the heat released by condensation of water vapour exceeds a certain quantity, the flow wi...A rapid expansion of moist air or steam in a supersonic nozzle gives rise to nonequilibrium condensation phenomena. Thereby, if the heat released by condensation of water vapour exceeds a certain quantity, the flow will become unstable and periodic flow oscillations of the unsteady condensation shock wave will occur. For the passive control of shock-boundary layer interaction using the porous wall with a plenum underneath, many papers have been presented on the application of the technique to transonic airfoil flows. In this paper, the passive technique is applied to three types of oscillations of the unsteady condensation shock wave generated in a supersonic nozzle in order to suppress the unsteady behavior As a result, the effects of number of slits and length of cavity on the aspect of flow field have been clarified numerically using a 3rd-order MUSCL type TVD finite-difference scheme with a second-order fractional-step for time integration.展开更多
文摘When condensation occurs in supersonic flow fields, the flow is thected by the latent heat released. In the present study, Navier-Stokes equations were solved numerically using a 3rd-order MUSCL type TVD finitedifference scheme with a second-order fractionabetep for time integration. Baldwin-Lomax model, that is the algebraic model, called the zero equation model was used in the computations. The effects of initial conditions (initial degree of supersaturation and total temperature in the reservoir) on condensing fiow of moist air in a supersonic circular half nozzle were investigated. In this case, the effect of condensation on the boundary layer was also discussed in detail. As a result, the simulated flow fields were compared with experimental data in good agreement, and the velocity and temperature profiles were largely changed by condensation.
文摘When condensation occurs in supersonic flow fields, the flow is affected by the latent heat released, and if the heat released exceeds a certain quantity, a condensation shock wave will occur There are many papers for the passive control of shock-boundary layer interaction using the porous wall with a plenum underneath on the application of the technique to transonic airfoil flows. In the present study, this passive technique is applied to the control of a steady condensation shock wave generated in a supersonic nozzle. In order to clarify the effect of the passive shockboundary layer control on condensation shock, Navier-Stokes equations were solved numerically using a 3rd-order MUSCL type TVD finite-difference scheme with a second-order fractional-step for time integration. As a result, the simulated flow fields were compared with experimental data in good agreement and the aspect of the flow field has been clarified.
文摘The homogeneous nucleation with subsequent spontaneous condensation of water, pentanol, and ethanol xupors in a carrier gas are investigated experimentally and theoretically in the expansion part of a shock tube. The precise pressure and Mcw measurements give additional information about the wetness, so that the nucleation and condensation rates which are closely coupled for stronger expansion rates are determined more accurately. Predictions of the principle of the minimum of entropy production are compared with experiments performed for water, ethanol and pentanol at different pressures.
文摘A rapid expansion of moist air or steam in a supersonic nozzle gives rise to nonequilibrium condensation phenomena. Thereby, if the heat released by condensation of water vapour exceeds a certain quantity, the flow will become unstable and periodic flow oscillations of the unsteady condensation shock wave will occur. For the passive control of shock-boundary layer interaction using the porous wall with a plenum underneath, many papers have been presented on the application of the technique to transonic airfoil flows. In this paper, the passive technique is applied to three types of oscillations of the unsteady condensation shock wave generated in a supersonic nozzle in order to suppress the unsteady behavior As a result, the effects of number of slits and length of cavity on the aspect of flow field have been clarified numerically using a 3rd-order MUSCL type TVD finite-difference scheme with a second-order fractional-step for time integration.
