Streambank seeps commonly originate from localized heterogeneity or preferential flow pathways (PFPs) in riparian floodplains. However, limited field data have been reported on ground water seep flows and solute transport to seeps from PFPs. The objective of this research was to build upon previous floodplain-scale investigations of PFPs by analyzing seep discharge and transport characteristics...

A monopropellant powered free piston hydraulic pump (FPHP) was designed as a human scale (1.0 to 3.0 kW) mobile robotics power supply. The FPHP utilized high concentration hydrogen peroxide, which decomposes into hot gas when exposed to a catalyst, as the monopropellant energy source. Energy was extracted from the hydrogen peroxide and transferred directly to hydraulic fluid by expanding the ho...

[1] Hyporheic exchange is an ecologically important process, controlling the nutrient supply in the upper sediments and thus benthic habitat quality. Hydraulic exchange at a riffle-pool sequence in the Lahn River, Germany, was analyzed using HEC-RAS to simulate the surface water flow as a boundary for the subsurface flow and MODFLOW, MODPATH, and MT3DMS to reproduce the transport in the subsurf...

The optimization of guide vane closing schemes (OGVCS) of pumped storage hydro units (PSHUs) is a cooperative control and optimal operation research field in renewable energy power generation technology. This paper presents an OGVCS model of PSHUs considering the rise rate of the unit rotational speed, the specific node pressure of each hydraulic unit, as well as various complicated hydraulic a...

In this paper, a new solution for an electro-hydraulic servo drive is proposed, which consists of two drives: one with hydraulic cylinder and rotary motor. the proposed drive, linear actuator attached to horizontal base motor mounted on piston rod. Thus, output signal lifting lowering element suspended rope. The paper describes structure, kinematics, dynamics, control novel drive. A valve propo...

This study focused on the diversity of bacterial communities from two series of two-stage constructed wetlands (CWs) treating tannery wastewater, under different hydraulic conditions. Series were separately planted with Typha latifolia and Phragmites australis in expanded clay aggregates and operated for 31 months. The effect of plant species, hydraulic loading and unit stage on bacterial commu...

Hydraulic redistribution (HR) occurs in many ecosystems; however, key questions remain about its consequences at the ecosystem level. The objectives of the present study were to quantify seasonal variation in HR and its driving force, and to manipulate the soil-root system to elucidate physiological components controlling HR and utilization of redistributed water. In the upper soil layer of a y...

determined in Scots pine (Pinus sylvestris L.) trees and stands from 7 to about 60 years of age. At the stand scale, leaf area index and net primary productivity (NPP, aboveplus belowground) increased and reached a plateau at about 25--30 and 15--20 years, respectively; both parameters declined in mature stands. Stand hydraulic conductance followed a similar trend to NPP, with a maximum at abou...

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 ...

Hydraulic fracturing in the fractured reservoirs plays a significant impact on the production rate. In this study, the hydrostatic condition is taken into account, the hydraulic fracturing operation was applied in every direction usinga written distinct element code. In each direction the hydraulic fracture is applied with different lengths and in each level the amount of production is predicte...