In order to improve the impact performance, the structure of hydraulic hammer should be optimized. In this paper, the ranges of eight vital structure parameters of piston and reversing valve system of hydraulic hammer were selected firstly; and then found the best value of different parameters under experiments with the method of computer optimization and the parametric analysis method provided...

Many studies have demonstrated linkages between the occurrence of fog and ecophysiological functioning in cloud forests, but few have investigated hydraulic functioning as a determining factor that explains sharp changes in vegetation. The objective of this study was to compare the plant water status during cloud-immersed and non-immersed conditions and hydraulic vulnerability in branches and r...

The speed and torque of the hydraulic motor is controlled by controlling the hydraulic valve pump connected to the hydraulic motor. An electro hydraulic valve coupled to a hydraulic motor is a common method of motor speed control in practice where both load pressure and speed change during operation. In this paper, system equations that include, flow and toque loss term has been established by ...

Presented herein is a methodology for the seismic and hydraulic assessment of the re-liability of urban water distribution networks (UWDN) based on general seismic assessment standards, as per the American Lifelines Alliance (ALA) guidelines, localized historical records of critical risk-of-failure metrics pertaining to the specific UWDN under assessment, and hydraulic simulations using adapted...

The saturated hydraulic conductivity of soil is needed for deteriming the agricultural and hydrological processes. The measurement techniques used to estimate such property remain hampered by extensive labor and time constraints. Both emitter discharge rate and steady saturated radius emerged from point source trickle irrigation on the soil surface were used to determine the saturated hydraulic...

A hydraulic jump is a sudden, rapid transition from a supercritical flow to a subcritical flow. At large inflow Froude numbers, the jump is characterized by a significant amount of entrained air. For this paper, the bubbly two-phase flow properties of steady and strong hydraulic jumps were investigated experimentally. The results demonstrate that the strong air entrainment rate and the depth-av...

Steady-state and transient one-dimensional unsaturated flow in vertically stratified porous media are examined. Saturated hydraulic conductivity and the alpha parameter of the exponential hydraulic conductivity function were assumed to vary from soil layer to soil layer. The use of effective unsaturated hydraulic conductivity to compute matric potential in the soil profile is demonstrated. Resu...

Tide-induced hydraulic head fluctuation results in significant airflow above the water table if the aquifer is air-confined, for example, if the aquifer is capped by low permeability materials. Hypothetical studies on the interaction between tidal fluctuation and airflow in coastal aquifers are carried out using an air–water two-phase numerical model. The results show that both the amplitude of...

The street hydraulic capacity to convey storm water is dictated by the street gutter geometry and hydraulic characteristics. With the consideration of traffic safety, the street hydraulic conveyance capacity is also subject to a reduction defined by the water velocity and flow depth in the street gutter. In this study, the street hydraulic equation is re-arranged to demonstrate that the water v...

Many temperate European tree species have their southernmost distribution limits in the Mediterranean Basin. The projected climatic conditions, particularly an increase in dryness, might induce an altitudinal and latitudinal retreat at their southernmost distribution limit. Therefore, characterizing the morphological and physiological variability of temperate tree species under dry conditions i...