Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 6 of 6 for “"on/off valves"”.
-
Achieving Efficient Control of Hydraulic Systems Using On/Off Valves
Hydraulic systems offer a range of benefits, such as high power density, ruggedness, linear actuation, and low cost, which have led to the use of hydraulic actuation systems throughout a wide range of industries. However, they also typically suffer from lower efficiency than competing methods of …
-
High Speed Rotary PWM On/Off Valves for Digital Control of Hydraulic Pumps and Motors
The research described in this dissertation focuses on the development of innovative on/off valves for high performance, high efficiency control of fixed displacement hydraulic pumps and motors. On/off valves, the hydro-mechanical equivalent of transistors, enable the application of digital control …
-
A low-leakage 3-way silicon microvalve
… presents an electrostatically actuated silicon microvalve designed for use in a miniature gas chromatography system for sample preparation and injection. In contrast to prior art, this design combines an integrated low voltage electrostatic microactuator as well as tight sealing capability. …
-
A new optimisation procedure for uncertainty reduction by intelligent wells during field development planning
… by substituting intelligent wells (IWs) for conventional wells. A previous study showed that IWs reduce the impact of geological uncertainty on the production forecast (Birchenko, Demyanov et al. 2008). This investigation has now been extended to the “dynamic” parameters (fluid contacts, …
-
A MEMS valve for the MIT Microengine
A microfabricated, electro-statically actuated, on/off gas valve made of silicon material has been designed, fabricated and tested. The valve will be a fuel control component in a micro-scale gas turbine engine. Room-temperature testing results using nitrogen have demonstrated repeatable valve …
-
Investigation of digital pump/motor control strategies
… fluid power systems, it has a significant impact on the efficiency of many fluid power systems. Motors are the most common rotary actuators in fluid power systems. State-of-the-art pump/motor units can achieve efficiencies higher than 90% when operating at maximum displacement; however, as the …