The Experts below are selected from a list of 57 Experts worldwide ranked by ideXlab platform
Zygmunt Paszota - One of the best experts on this subject based on the ideXlab platform.
-
theoretical and mathematical models of the torque of mechanical losses in the pump used in a hydrostatic drive
Polish Maritime Research, 2011Co-Authors: Zygmunt PaszotaAbstract:The paper presents theoretical and mathematical models of the torque of mechanical losses in the pump with theoretical (constant) capacity qPt per one Shaft Revolution (with constant theoretical working volume VPt) and geometrical (variable) capacity qPgv per one Shaft Revolution (with variable volume VPgv). The models may be used in the laboratory and simulation investigations of the pump energy efficiency and the hydrostatic drive efficiency.
-
graphical presentation of the power of energy losses and power developed in the elements of hydrostatic drive and control system part ii rotational hydraulic motor speed parallel throttling control and volumetric control systems
Polish Maritime Research, 2008Co-Authors: Zygmunt PaszotaAbstract:Paper presents graphical interpretation of the power of energy losses in the hydrostatic drive and control system elements and also of the power developed by those elements. An individual system fed by a constant capacity pump, where rotational hydraulic motor speed control is effected by a parallel throttling control system, is analyzed and also a system with the rotational hydraulic motor speed volumetric control by a variable capacity pump, an individual system with a rotational hydraulic motor volumetric speed control by means of a simultaneous change of the pump capacity per one Revolution and change of the motor capacity per one Revolution, the system operating at the constant pressure in the pump discharge conduit equal to the nominal pressure of the system: pP2 = pn and central system (with situated in parallel and simultaneously operating motors) with volumetric speed control of each rotational hydraulic motor by a motor secondary circuit assembly, the system fed by a pump with variable capacity per one Shaft Revolution fitted with pressure regulator pP2 = pn.
Rui Xie - One of the best experts on this subject based on the ideXlab platform.
-
measurement method of vehicle Shaft Revolution speed based on capacitive grating sensor
International Conference on Robotics and Automation, 2013Co-Authors: Chang Xin Chen, Tie Hua, Hong Jin, Rui XieAbstract:Due to the narrow interior space of vehicle, the compact structure limited the method of Revolution speed measurement based on photoelectric and magnetoelectric, so a new measurement method based on capacitive grating sensor is presented here. The sensor will output alternating capacitance signal by fixed the mobilizable grating on the Shaft and fixed the stator grating on the bracket. The capacitance signal will turn into the corresponding sine wave signal to the speed through differential pulse width modulation circuit, subtraction circuit and low-pass filter circuit, and will output a square wave of the same frequency with the sine wave through phase locked loop circuit. Then the speed measurement will be realized by counting the signal pulse. Experiments show that this method has the characteristics of non-contact measuring and high sensitivity.
Jose Garciabravo - One of the best experts on this subject based on the ideXlab platform.
-
the determination of the theoretical stroke volume of hydrostatic positive displacement pumps and motors from volumetric measurements
Energies, 2019Co-Authors: Gijsbe Toe, Jack Johnso, Joh Montague, Ke Torres, Jose GarciabravoAbstract:This document presents a revised translation to the English language work developed more than 40 years ago by the first author. It further summarizes a common misinterpretation of the method and succinctly describes a graphical procedure to correctly determine the derived displacement volume of a pump or a motor. The original work contains a directive for the determination of the derived displacement volume of hydrostatic positive displacement pumps and motors, from volumetric (flow and speed) measurements. The procedure is based on the definition of the derived displaced volume, defined as: The volumetric flow pushed or admitted by hydrostatic positive displacement pumps and motors per (Shaft) Revolution, at zero internal and external leakage flow conditions.
Chang Xin Chen - One of the best experts on this subject based on the ideXlab platform.
-
measurement method of vehicle Shaft Revolution speed based on capacitive grating sensor
International Conference on Robotics and Automation, 2013Co-Authors: Chang Xin Chen, Tie Hua, Hong Jin, Rui XieAbstract:Due to the narrow interior space of vehicle, the compact structure limited the method of Revolution speed measurement based on photoelectric and magnetoelectric, so a new measurement method based on capacitive grating sensor is presented here. The sensor will output alternating capacitance signal by fixed the mobilizable grating on the Shaft and fixed the stator grating on the bracket. The capacitance signal will turn into the corresponding sine wave signal to the speed through differential pulse width modulation circuit, subtraction circuit and low-pass filter circuit, and will output a square wave of the same frequency with the sine wave through phase locked loop circuit. Then the speed measurement will be realized by counting the signal pulse. Experiments show that this method has the characteristics of non-contact measuring and high sensitivity.
Steven Chatterton - One of the best experts on this subject based on the ideXlab platform.
-
nonlinear effects caused by coupling misalignment in rotors equipped with journal bearings
Mechanical Systems and Signal Processing, 2012Co-Authors: P Pennacchi, Andrea Vania, Steven ChattertonAbstract:Abstract Misalignment is one of the most common sources of trouble of rotating machinery when rigid couplings connect the Shafts. Ideal alignment of the Shafts is difficult to be obtained and rotors may present angular and/or parallel misalignment (defined also as radial misalignment or offset). During a complete Shaft Revolution, a periodical change of the bearings load occurs in hyperstatic Shaft-lines, if coupling misalignment between the Shafts is excessive. If the rotating machine is equipped with fluid-film journal bearings, the change of the loads on the bearing causes also the variation of their instantaneous dynamic characteristics, i.e. damping and stiffness, and the complete system cannot be considered any longer as linear. Despite misalignment is often observed in the practice, there are relatively few studies about this phenomenon in literature and their results are sometimes conflicting. The authors aim at modeling accurately this phenomenon, for the first time in this paper, and giving pertinent diagnostic information. The proposed method is suitable for every type of Shaft-line supported by journal bearings. A finite element model is used for the hyperstatic Shaft-line, while bearing characteristics are calculated by integrating Reynolds equation as a function of the instantaneous load acting on the bearings, caused also by the coupling misalignment. The results obtained by applying the proposed method are shown by means of the simulation, in the time domain, of the dynamical response of a hyperstatic Shaft-line. Nonlinear effects are highlighted and the spectral components of the system response are analyzed, in order to give diagnostic information about the signature of this type of fault.