Tractor hydraulic power is used on a wide range of agricultural implements; however, the availability of operational hydraulic data at points other than full engine throttle position is limited. Operators could utilize this hydraulic data to maximize field efficiency and minimize machinery costs when determining suitable machinery for field operations. A field usable hydraulic test apparatus ca...

hydraulic conductivity variations around the boreholes in uniformly graded sands for cyclic water injection pressure have been evaluated by laboratory tests. prototype laboratory devices have been designed and constructed for this research. the cell has a capability to model the well, the boundary condition and to measure the hydraulic conductivity. while increasing water injection pressure, hy...

1 Abstract The paper presents a hydraulic astable multivibrator system. The system consists of hydraulic resistors, hydraulic capacitors and hydraulic pressure controlled valves. The system is designed, realised and tested. The measured system behaviour agrees well with the model simulations. The free running frequency of the multivibrator is 0.18 Hz and the output pressure swing is 90% of the ...

the narrow operating window between pore pressure and fracture pressure makes drilling difficult in some operations. a feasibility study of managed pressure drilling (mpd) is carried out on iran darquain oil field. the previous wells drilled in this field showed that mud returns were lost during drilling gadvan formation. the present work addresses this problem by means of surface back pressure...

Hydraulic conductivity variations around the boreholes in uniformly graded sands for cyclic water injection pressure have been evaluated by laboratory tests. Prototype laboratory devices have been designed and constructed for this research. The cell has a capability to model the well, the boundary condition and to measure the hydraulic conductivity. While increasing water injection pressure, hy...

This paper denouements the study of operating parameters of a hydraulic transmission system with and without the application of hydraulic accumulator. In this respect, the hydraulic system, designed in the open circuit mode, consists of the fixed displacement hydraulic pump which gives pressured fluid to the hydro-motor and charges the accumulator as well. The load on the motor is controlled hy...

The narrow operating window between pore pressure and fracture pressure makes drilling difficult in some operations. A feasibility study of managed pressure drilling (MPD) is carried out on Iran Darquain oil field. The previous wells drilled in this field showed that mud returns were lost during drilling Gadvan formation. The present work addresses this problem by means of surface back pressure...

Numerical simulation is very useful for understanding the hydraulic fracturing mechanism. In this paper, we simulate the hydraulic fracturing using the distinct element approach, to investigate the effect of some critical parameters on hydraulic fracturing characteristics. The breakdown pressure obtained by the distinct element approach is consistent with the analytical solution. This indicates...

abstract among activities that can be used to prevent piping phenomena and reduce seepage and exit gradient are installation of cutoff wall and drain under hydraulic structures. hence in this study, to investigating the influence of each mentioned parameter on uplift force and exit gradient a computer model has developed in which general equation of fluid flow into the isotropic and anisotropic...

OBJECTIVES Leaflet injury has been documented to occur during the deployment of valved stents (VSs). The pathological aspects, however, of this injury are difficult to quantify. Conversely, the hydraulic conductance of a (pericardial) membrane may be easily determined. The impact of crimping and deployment of VS on this parameter was therefore investigated. METHODS Bovine pericardial square (...