The Singular Integral Operators Method (S.I.O.M.) is applied to the determination of the free-surface profile of an un-steady flow over a spillway, which defines a classical hydraulics problem in open channel flow. Th...The Singular Integral Operators Method (S.I.O.M.) is applied to the determination of the free-surface profile of an un-steady flow over a spillway, which defines a classical hydraulics problem in open channel flow. Thus, with a known flow rate Q, then the velocities and the elevations are computed on the free surface of the spillway flow. For the numerical evaluation of the singular integral equations both constant and linear elements are used. An application is finally given to the determination of the free-surface profile of a special spillway and comparing the numerical results with corresponding results by the Boundary Integral Equation Method (B.I.E.M.) and by using experiments.展开更多
Li Hailong瞬态导气率模型无需测量通过样品的气体通量,相对传统稳态测量法具有测量时间短、对样品结构破坏小等突出优点,但模型的关键参数s即样品密封端压力动态变化与时间t之间关系计算过程复杂,致使其应用不便。因此,本文在Li Hailon...Li Hailong瞬态导气率模型无需测量通过样品的气体通量,相对传统稳态测量法具有测量时间短、对样品结构破坏小等突出优点,但模型的关键参数s即样品密封端压力动态变化与时间t之间关系计算过程复杂,致使其应用不便。因此,本文在Li Hailong导气率测算模型基础上对参数s计算过程进行了简化,并用稳态法对简化后的模型进行验证。室内对40组土样导气率测量结果表明:简化解s0即Lnp(t)与时间t之间存在Kirkham提出的瞬态模型线性关系;以原模型参数s为标准,简化解s0与参数s相对误差变化幅度小于0.5%,整体相对误差小。展开更多
文摘The Singular Integral Operators Method (S.I.O.M.) is applied to the determination of the free-surface profile of an un-steady flow over a spillway, which defines a classical hydraulics problem in open channel flow. Thus, with a known flow rate Q, then the velocities and the elevations are computed on the free surface of the spillway flow. For the numerical evaluation of the singular integral equations both constant and linear elements are used. An application is finally given to the determination of the free-surface profile of a special spillway and comparing the numerical results with corresponding results by the Boundary Integral Equation Method (B.I.E.M.) and by using experiments.
