This paper deals with the design of a hydraulicmechanical load-sensing system using computer modelling and simulation in an object-oriented programming environment. As initial, the scheme of a hydraulic-mechanical load-sensing system of Bosch GMbH has been taken. A modified scheme of the system is proposed. The object-oriented mathematical model of the system is composed. The approach is based ...

This paper reports on an investigation of the possible influence of modelling errors on the relationship between the entropy and hydraulic reliability of water distribution systems. The errors are due to minor differences between the design optimisation and subsequent simulation models, which lead to small discrepancies between the capacity of the network and the required supply. Pressure-depen...

Leakage rates are evaluated for a landfill barrier system having a compacted clay liner (CCL) underlain by a vadose zone of variable thickness. A numerical unsaturated flow model SEEP/W is used to simulate the moisture flow regime and steady-state leakage rates for the cases of unsaturated zones with different soil types and thicknesses. The results of the simulations demonstrate that harmonic ...

Large hydraulic structures are of major importance to sustained life-support systems and have an impact on the environment. Dams, reservoirs and open canals are such structures, the impact of which has been duly appreciated and addressed in environmental impact assessments and side-effects amelioration programs. Less obvious, but of vital importance, is the impact of urban drainage systems on h...

Hydraulic machines have been widely used in a variety of high power applications. Typically these machines are operated by an operator. In past research the interaction safety between the operator and the machine was seldom investigated. This dissertation addressess the interaction stability issue by exploiting the safety guarantees offered by passive systems. The hydraulic machine considered i...

For decades it has been assumed that the largest vessels are generally found in roots and that vessel size and corresponding sapwood area-specific hydraulic conductivity are acropetally decreasing toward the distal twigs. However, recent studies from the perhumid tropics revealed a hump-shaped vessel size distribution. Worldwide tropical perhumid forests are extensively replaced by agroforestry...

This paper focuses on optimal hydraulic component selection for electrohydraulic systems used in high performance servo tasks. Dynamic models of low complexity are proposed that describe the salient dynamics of basic electrohydraulic equipment. Rigid body equations of motion, the hydraulic dynamics and typical trajectory inputs are used in conjunction with optimization techniques, to yield an o...

This paper describes the development of linear parameter varying (LPV) models and an LPV-H∞ controller for one degree of freedom (DoF) electro-hydraulic systems. A virtual set-up consists of a hydraulic actuator driven by a servovalve and supplied from a constant-pressure power unit. The LPV models are derived based on two techniques: black-box modeling and the analytical description of the sys...

A novel model-based controller for 6 degree-of-freedom (DOF) hydraulic driven parallel manipulator considering the nonlinear characteristic of hydraulic systems-proportional plus derivative with dynamic gravity compensation controller is presented, in order to improve control performance and eliminate steady state errors. In this paper, 6-DOF parallel manipulator is described as multi-rigid-bod...

The increasing demand for sufficient and clean energy forces industrial and service companies to align their strategies towards efficient consumption. This trend refers also to the residential building sector. There, large amounts of energy consumption are caused by house and facility heating. Many of the operated hot water heating systems lack hydraulic balanced working conditions for heat dis...