The near field stahility and mixing characteristics of buoyant jets produced by thermal diffuse in quiescent shallow water are inw.stigated numerically to predict under what combinations of discharge and ambient chara...The near field stahility and mixing characteristics of buoyant jets produced by thermal diffuse in quiescent shallow water are inw.stigated numerically to predict under what combinations of discharge and ambient characteristics the near field will be stable or unstable, Analyses for different discharging types show that the discharge stability is purely dependent on the near-field hehavior of the jets, or the dynam ic interaction of the buoyant jet region, the surface impinge ment region and the internal hydraulic jump region, and is independent of the far-field geometry of the receiving water. The stability criterion is a function of the relative submerged depth, and source densimetrie Froude number.展开更多
The k-epsilon model was applied to establish the mathematical model of vertical round buoyant jet discharging into confined depth, and it was solved using the Hybrid Finite Analytic Method (HFAM). The numerical predic...The k-epsilon model was applied to establish the mathematical model of vertical round buoyant jet discharging into confined depth, and it was solved using the Hybrid Finite Analytic Method (HFAM). The numerical predictions demonstrate two generic flow patterns for different jet discharge and environmental parameters: (ⅰ)a stable buoyant flow discharge with the mixed fluid leaving the near-field warm in a surface warm water layer; (ⅱ)an unstable buoyant flow discharge with recirculation and re-entrainment of warm water in the near field. Furthermore, the mixing characters of vertical round buoyant jet were numerically predicted. Both the stability criterion and numerical predictions of bulk dilutions are in excellent agreement with Lee and Jirka's experiments and theory.展开更多
文摘The near field stahility and mixing characteristics of buoyant jets produced by thermal diffuse in quiescent shallow water are inw.stigated numerically to predict under what combinations of discharge and ambient characteristics the near field will be stable or unstable, Analyses for different discharging types show that the discharge stability is purely dependent on the near-field hehavior of the jets, or the dynam ic interaction of the buoyant jet region, the surface impinge ment region and the internal hydraulic jump region, and is independent of the far-field geometry of the receiving water. The stability criterion is a function of the relative submerged depth, and source densimetrie Froude number.
文摘The k-epsilon model was applied to establish the mathematical model of vertical round buoyant jet discharging into confined depth, and it was solved using the Hybrid Finite Analytic Method (HFAM). The numerical predictions demonstrate two generic flow patterns for different jet discharge and environmental parameters: (ⅰ)a stable buoyant flow discharge with the mixed fluid leaving the near-field warm in a surface warm water layer; (ⅱ)an unstable buoyant flow discharge with recirculation and re-entrainment of warm water in the near field. Furthermore, the mixing characters of vertical round buoyant jet were numerically predicted. Both the stability criterion and numerical predictions of bulk dilutions are in excellent agreement with Lee and Jirka's experiments and theory.
