due to availability of proper materials in landfills (at most parts of iran especially in kahrizak) and also less expenditure of this liner in comparison with other liners it can be count as an acceptable choice. different studies imply that one of the most important factors for soil liner selection is local conditions and also liner compatibility with generated leachate in studied site. hydrau...

High servo control response and high energy-efficiency are requested in hydraulic servo systems of current hydraulic machines. This investigation concurrently implements energy-saving control and velocity-force control for simultaneously realizing high velocity-force control response and high energy-efficiency for hydraulic valve-controlled cylinder systems. The velocity-force control of the hy...

An experimental testing program was conducted to quantify leakage through a geomembrane liner system when subjected to high hydraulic heads. Leakage through geomembranes is mainly due to the presence of defects, which may occur during installation and operation. Previous studies focused on leakage through landfill liners (i.e., low hydraulic heads) have led to analytical models and simplified e...

A lysimeter station has been set up by AMRA for the study of the reactive transport of contaminants in soil at the field-scale. It consists of eight lysimeters that can operate individually and simultaneously. Each lysimeter is a steel cylinder (diameter 1.14m, height 2m) filled with an undisturbed soil monolith, whose upper surface is directly exposed to the external environmental agents. A se...

Hydraulic systems are widely used in industry because of the advantages of their small size-to-power ratios and their ability to produce very large linear force and torque. There are tendencies for compact electro-hydraulic systems which deliver powerful, linear movement having hydraulic oil circulation only when operating. This paper investigates directly driven hydraulic setup for non-road mo...

As worldwide automotive ownership is set to exceed 2 billion vehicles by 2030 [1], environmental and economical pressures on the automotive industry mean there is a trend to reduce harmful greenhouse gas emissions whilst simultaneously improving fuel economy. The use of electrical hybrid, start-stop idling and materials light-weighting are some of the technological solutions which can offer eff...

The present paper describes dynamic modelling, results of simulation and experimental investigation of a hydraulic stepper cylinder, which find application in manipulators and robots. The method of bond graph is used for modelling of the dynamics of the considered cylinder design. First, an initial digital simulation is performed in order to calculate basic dynamic characteristics of the cylind...

In order to study the numerical control (NC) servo press hydraulic control system and its control algorithm. The numerical control servo press performance and control principle of hydraulic control system are analyzed. According to the flow equation of the hydraulic control valve, hydraulic cylinder flow continuity equation and the force balance equation of the hydraulic cylinder with load pres...