Servo-hydraulic control is regarded as a key technology in most mechanical testing systems for the investigation of strength and fatigue properties of materials, mechanical components and structures. High performance but robust control strategies are necessary as part of the test control system to ensure high test quality and reproducible test results which are of special importance when consid...

in this research, in order to develop new relationships with reasonable accuracy for estimation of the ‎submerged hydraulic jump characteristics, a study has been conducted experimentally. experiments have ‎been done in a rectangular channel with a length of 9 m, a width of 0.5 m and a depth of 0.45 m. froude ‎numbers in these tests range from 3.5 to 11.5 and between submergence ratios of 0.1 t...

We present an investigation of the scale dependence of hydraulic 3 parameters in fractured media based on the concept of transfer functions (TF). 4 TF methods provide an inexpensive way to perform aquifer parameter es5 timation, as they relate the fluctuations of an observation time series (hy6 draulic head fluctuations) to an input function (aquifer recharge) in frequency 7 domain. Fractured m...

Longwall mining is the only technically proven and established method worldwide for coal extraction at greater depth. In this paper, 2D plane strain finite element models of longwall panels are developed and analyzed to understand the interaction of hydraulic powered support with surrounding rock strata. Based on Indian geomining conditions, finite element models are developed including the str...

Operational failures in centrifuge pumps could be hydraulic or mechanical. However, most of these mechanical and hydraulic failures are connected cause of their operational nature and finding the right cause is due to considering numerous mechanical and hydraulic signs and parameters in pumps. On the other hand, due to non-linear and fluctuant behavior of pumps in the matter of time and not pre...

This paper is concerned with real-time optimal-tuning PID control design for industrial hydraulic systems. Several optimal-tuning controller design techniques are used for a hydraulic position control system. After analysis on the system, a nonlinear dynamical model is derived. A nonlinear PID control scheme with inverse of dead zone is introduced to overcome the dead zone in this hydraulic sys...

Hydraulic water distribution system (WDS) simulation models are widely used by planners, water utility personnel, consultants and many others involved in analysis, design, operation or maintenance of water distribution systems. Similarly, water quality models that work in concert with hydraulic models are now commonly used to simulate the dispersion of and changes in water quality in a water di...

The identification of freezing-thawing soil hydraulic properties is the basis and key problem of studying soil water movement. Current identifying methods of the properties have many limitations, such as big error, high uncertainty and low operability. Thus, the identifying method of freezingthawing soil hydraulic properties was researched in the research. The estimating parameters of soil free...

We present in this paper some results concerning the least sqaures estimation of parameters in a groundwater ow model. As is typically the case in eld studies, the form of the data is pointwise observation of hydraulic head and hydraulic conductivity at a discrete collection of observation well sites. We prove continuous dependence results for the solution of the groundwater ow equation, with r...

the hydraulic characteristic of an up-flow anaerobic sludge blanket fixed film (uasb-ff) were studied by changing two important hydraulic factors that can impact significantly on the hydraulic regime of the uasb-ff bioreactor: the up-flow velocity (vup) and biogas production rate (qg). the analysis of the reactor hydraulic performance was performed by studying hydraulic residence time distribut...