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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.

Energy Consumption and Dynamic Behaviour Analyses in Single-Rod Hydraulic Actuation of Mobile Machines

Mazloumpour, Mohammad E 08 January 2014 (has links)
This thesis investigates the performance of single-rod hydraulic actuation of mobile machines. The performance is evaluated by studying the energy consumption and the dynamic performance of such actuation systems. Presently, valve-controlled systems control actuators of mobile machines. However, they are inefficient in terms of energy consumption. Therefore, low-energy consumption pump-controlled systems have been proposed. This thesis studies the energy consumption of pump-controlled systems developed by Wendell and Rahmfeld-Ivantysynova and valve-controlled systems. This thesis also compares the dynamic performance of the above pump-controlled systems with the load sensing valve-controlled system. A set of evaluation tests is conducted on single-rod hydraulic actuations that are simulated using the Automation Studio® software. Based on a cycle test, the energy consumption of Wendell’s pump-controlled system is 60% lower than that of the load sensing system. However, the above pump-controlled system leads to the poor dynamic behavior of a single-rod cylinder.

High Pressure Hydraulic Supply System Model

Mock, William H. 03 1900 (has links) (PDF)
Florida Technological University College of Engineering Thesis / A mathematical model is derived to provide quasi-steady state predictions of the performance of a high pressure hydraulic supply system, using equations which govern the physical processes as opposed to equations which match input-output characteristics. Model equations are developed to describe the operation of the power source, control valves, energy source, gas side of the system, hydraulic accumulator, the motorpump, and hydraulic side of the system. The accuracy of the model is then checked by inserting known parameters from a previously developed control system and comparing model predictions with performance data from this system. / M.S. / Masters / Engineering / Engineering / 40 p. / vii, 40 l. : ill. ; 28 cm.

Design and characterization of mechanical mesopumps

Al-Rifai, Omar M. Haik, Yousef, January 2006 (has links)
Thesis (M.S.)--Florida State University, 2006. / Advisor: Yousef Haik, Florida State University, College of Engineering, Dept. of Mechanical Engineering. Title and description from dissertation home page (viewed June 9, 2006). Document formatted into pages; contains ix, 57 pages. Includes bibliographical references.

Design of a electrohydraulic positioning system

Bentz, Delone Reinholt, January 1970 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1970. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

The design of hydraulic valve circuit under microprocessor control for increasing efficiency of hydraulic servo system

Punyapas, Noparut 05 1900 (has links)
No description available.

Selection considerations for a servovalve

Niemas, Frank J. 09 1900 (has links) (PDF)
Florida Technological University College of Engineering Thesis / Servovalves are a key factor in determining the performance characteristics of an electrohydraulic position servo. This paper examines the interrelationships between servovalve parameters and system requirements. A brief description of the configuration and operation of a typical servovalve is presented. Key servovalve parameters are identified, defined, and discussed. System performance considerations are identified, and the interrelationships between system requirements and servovalve parameters are examined. Examples of servovalve parameters for missile, aircraft and industrial systems are given to illustrate the effect of system requirements on a servovalve. Finally, general guide-lines for selecting and specifying servovalve parameters are given. / M.S. / Masters; / College of Engineering / Engineering / Engineering / 60 p. / vi, 58 l. : ill., diagrs., graphs ; 28 cm.

Simulation of growth of multiple interacting 3D cracks in hydraulic fractures driven by inviscid fluid

Dana, Saumik P. 17 February 2015 (has links)
In this report, we develop a computational procedure to investigate propagation of 3D cracks in isotropic linearly elastic media in a 2D framework. We reduce the 3D weakly singular, weak-form traction integral equation to its 2D analog by introducing a constraint on crack profile in out-of-plane direction. Symmetric Galerkin boundary element method based on the obtained 2D weak-form traction integral equation is adopted to model these fractures. In particular, we consider multiple interacting cracks in unbounded domain subject to internal pressure to model hydraulic fracture. / text

Flow in multiple-orifice plate columns

關永強, Kwan, Wing-keung. January 1981 (has links)
published_or_final_version / Mechanical Engineering / Master / Master of Philosophy

Mechanics of complex hydraulic fractures in the Earth's crust

Sim, Youngjong. January 2004 (has links) (PDF)
Thesis (Ph. D.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2005. / Puzrin, Alexander M., Committee Member ; Rix, Glenn J., Committee Member ; Mayne, Paul W., Committee Member ; Lowell, Robert P., Committee Member ; Germanovich, Leonid, Committee Chair ; Xu, Wenyue, Committee Member ; Van Dyke, Peter, Committee Member. Vita. Includes bibliographical references.

Cross section spacing considerations in the computation of gradually varied flow profiles for open channels

Bennett, David J. January 1980 (has links)
Thesis (M.S.)--University of Wisconsin--Madison. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 100-102).

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