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Results for “Variable speed pump”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1985

Phase change water processing for Space Station

The use of a vapor compression distillation subsystem (VCDS) for water recovery on the Space Station is analyzed. The self-contained automated system can process waste water at a rate of 32.6 kg/day and requires only 115 W of electric power. The improvements in the mechanical components of VCDS are studied. The operation of VCDS in the normal mode is examined. The VCDS preprototype is evaluated based on water quality, water production rate, and specific energy. The relation between water production rate and fluids pump speed is investigated; it is concluded that a variable speed fluids pump will optimize water production. Components development and testing currently being conducted are described. The properties and operation of the proposed phase change water processing system for the Space Station, based on vapor compression distillation, are examined.

Zdankiewicz, E. M.↗
NASA NTRS1982

Simpler Variable-Speed Drive for Fan or Pump

Static pressure developed by a fan or pump is used directly to control its speed in a new drive unit. System is simpler and more economical than many other speed controllers, although it is less accurate and has a narrower speed range. However, since very accurate control is not usually required for fans and pumps, unit would work well in many applications.

Obler, H. D.↗
NASA NTRS1994

Dewatering of contaminated river sediments

Dewatering of slurries has been successfully accomplished by the proper use of polymers in flocculating the fine particulate matter suspended in mineral processing streams. The U.S. Bureau of Mines (USBM) entered into a cooperative research effort with the U.S. Army Corps of Engineers (Corps) for the purpose of testing and demonstrating the applicability of mining flocculation technology to dredging activities associated with the removal of sediments from navigable waterways. The Corps has the responsibility for maintaining the navigable waterways in the United States. Current technology relies primarily on dredging operations which excavate the material from the bottom of waterways. The Corps is testing new dredging technology which may reduce resuspension of sediments by the dredging operation. Pilot plant dredging equipment was tested by the Corps which generated larger quantities of water when compared to conventional equipment, such as the clam shell. The transportation of this 'excess' water adds to the cost of sediment removal. The process developed by the USBM consists of feed material from the barge being pumped through a 4-in line by a centrifugal pump and exiting through a 4-in PVC delivery system. A 1,000-gal fiberglass tank was used to mix the polymer concentrate. The polymer was pumped through a 1-in line using a variable speed progressive cavity pump and introduced to the 4-in feed line prior to passing through a 6-in by 2-ft static mixer. The polymer/feed slurry travels to the clarifying tank where the flocculated material settled to the bottom and allowed 'clean' water to exit the overflow. A pilot scale flocculation unit was operated on-site at the Corps' 'Confined Disposal Facility' in Buffalo, NY.

Church, Ronald H.↗
NASA NTRS1933

Rates of fuel discharge as affected by the design of fuel-injection systems for internal-combustion engines

Using the method of weighing fuel collected in a receiver during a definite interval of the injection period, rates of discharge were determined, and the effects noted, when various changes were made in a fuel-injection system. The injection system consisted primarily of a by-pass controlled fuel pump and an automatic injection valve. The variables of the system studied were the pump speed, pump-throttle setting, discharge-orifice diameter, injection-valve opening and closing pressures, and injection-tube length and diameter.

Gelalles, A G↗
NASA NTRS1982

Description of the 3 MW SWT-3 wind turbine at San Gorgonio Pass, California

The SWT-3 wind turbine, a microprocessor controlled three bladed variable speed upwind machine with a 3MW rating that is presently operational and undergoing system testing, is discussed. The tower, a rigid triangular truss configuration, is rotated about its vertical axis to position the wind turbine into the prevailing wind. The blades rotate at variable speed in order to maintain an optimum 6 to 1 tip speed ratio between cut in and fated wind velocity, thereby maximizing power extraction from the wind. Rotor variable speed is implemented by the use of a hydrostatic transmission consisting of fourteen fixed displacement pumps operating in conjunction with eighteen variable displacement motors. Full blade pitch with on-off hydraulic actuation is used to maintain 3MW of output power.

Rybak, S. C.↗
NASA NTRS1978

Preliminary design package for solar heating and cooling systems

Summarized preliminary design information on activities associated with the development, delivery and support of solar heating and cooling systems is given. These systems are for single family dwellings and commercial applications. The heating/cooling system use a reversible vapor compression heat pump that is driven in the cooling mode by a Rankine power loop, and in the heating mode by a variable speed electric motor. The heating/cooling systems differ from the heating-only systems in the arrangement of the heat pump subsystem and the addition of a cooling tower to provide the heat sink for cooling mode operation.

Source record↗
NASA NTRS1983

Variable speed drive

A variable speed drive wherein a first embodiment is comprised of a pivotally mounted prime mover coupled to a rotary fluid output device, such as a fan or pump, through a variable and fixed pulley drive arrangement is described. The pivotal position of the prime mover and accordingly the pitch diameter of variable pulley means is controlled in accordance with fluid motor means coupled to the prime mover. This is actuated in response to a fluid feedback control signal derived from a sensed output of the rotary fluid output device. The pivotal motion of the prime mover imparts an arcuate motion to the variable pulley means which effects a speed variation of the rotary fluid output device in accordance with the variation of the pitch diameter ratio of opposing variable and fixed pulley means.

Obler, H. D.↗
NASA NTRS2013

Recommended Practice for Pressure Measurements and Calculation of Effective Pumping Speeds During Electric Propulsion Testing

The electric propulsion community has been implored to establish and implement a set of universally applicable test standards during the research, development, and qualification of electric propulsion systems. Variability between facility-to-facility and more importantly ground-to-flight performance can result in large margins in application or aversion to mission infusion. Performance measurements and life testing under appropriate conditions can be costly and lengthy. Measurement practices must be consistent, accurate, and repeatable. Additionally, the measurements must be universally transportable across facilities throughout the development, qualification, spacecraft integration, and on-orbit performance. A recommended practice for making pressure measurements, pressure diagnostics, and calculating effective pumping speeds with justification is presented.

Dankanich, John W.↗
NASA NTRS1981

Control system development for an organic Rankine cycle engine

The development of a control logic to govern the toluene throttle valve and verify the stability of the speed control approach for multiple engines connected to a 1 MWe point focus solar generator installation for distributed applications is presented. The toluene is is pumped by booster and main feed pumps through a regenerator to the parabolic focus receiver, with the flow rate controlled by a valve to remain at critical level of 4.1 MPa. The valve changes the inlet pressure at the turbine nozzle block. Each concentrator would produce 76 kWth and 20 kWe. Dynamic variables in the logic account for insolation variation, fluid temperature, ac grid voltage, the thermal dynamics of the regenerator, and variations in the head supplied by the feed pump. Separate analyses are presented for the turbine shaft speed and toluene loop dynamics. The resulting logic is considered preliminary and suitable only in full insolation conditions. Extension of the model to nonlinear perturbations is indicated.

Bergthold, F. M., Jr.↗
NASA NTRS1982

Efficient Energy-Storage Concept

Space-platform energy-storage and attitude-stabilization system utilizes variable moment of inertia of two masses attached to ends of retractable cable. System would be brought to its initial operating speed by gravity-gradient pumping. When fully developed, concept could be part of an orbiting solar-energy collection system. Energy would be temporarily stored in system then transmitted to Earth by microwaves or other method.

Brantley, L. W. J.↗
NASA NTRS1931

Penetration and Duration of Fuel Sprays from a Pump Injection System

High-speed motion pictures were taken of individual fuel sprays from a pump injection system. The changes in the spray-tip penetration with changes in the pump speed, injection-valve opening and closing pressures, discharge-orifice area, injection-tube length and diameter, and pump throttle setting were measured. In addition, the effects of the variables on the time lag and duration of injection can be controlled by the dimensions of the injection tube, the area of the discharge orifice, and the injection-valve opening and closing pressures.

Rothrock, A M↗
NASA NTRS2021

Test Bed for Investigating Anomalous Pump Behavior in a Single Phase Mechanically Pumped Flow Loop and Lessons Learned

NASA’s Europa Clipper mission is tasked with investigating the habitability of this icy moon of Jupiter and determining if it is capable of supporting life. The suite of powerful instruments necessary for this mission, combined with the harsh environment, require an elaborate single phase, mechanically pumped flow loop (MPFL) to redistribute waste heat around the spacecraft, thus minimizing energy requirements and avoiding the need for constant heating of the propulsion tanks. At the heart of this MPFL is a pump which will circulate fluid for the entirety of the 12-year mission; however, during initial qualification testing, anomalous behavior raised serious concerns regarding the pump and system design. Due to the critical nature of the pump, a major investigation was launched to evaluate the pump, system design, and the testing methodology employed to investigate this anomaly. This investigation resulted in a highly detailed analysis of the test loop, revised procedures, and the isolation/removal of variables impacting the quality of the observed pump behavior. The resulting test loop permitted comprehensive monitoring of the pump in the MPFL, including: flow rate, inlet and outlet static pressures, temperature, power consumption, and pump speed. Additionally, the investigation of the anomaly revealed several key lessons learned and helped institute a new set of best practices for future MPFL tests.

Miers, Collier↗
NASA NTRS1982

Preliminary results on performance testing of a turbocharged rotary combustion engine

The performance of a turbocharged rotary engine at power levels above 75 kW (100 hp) was studied. A twin rotor turbocharged Mazda engine was tested at speeds of 3000 to 6000 rpm and boost pressures to 7 psi. The NASA developed combustion diagnostic instrumentation was used to quantify indicated and pumping mean effect pressures, peak pressure, and face to face variability on a cycle by cycle basis. Results of this testing showed that a 5900 rpm a 36 percent increase in power was obtained by operating the engine in the turbocharged configuration. When operating with lean carburetor jets at 105 hp (78.3 kW) and 4000 rpm, a brake specific fuel consumption of 0.45 lbm/lb-hr was measured.

Meng, P. R.↗
NASA NTRS1950

Preliminary Performance Data on Westinghouse Electronic Power Regulator Operating on J34-WE-32 Turbojet Engine in Altitude Wind Tunnel

The behavior of the Westinghouse electronic power regulator operating on a J34-WE-32 turbojet engine was investigated in the NACA Lewis altitude wind tunnel at the request of the Bureau of Aeronautics, Department of the Navy. The object of the program was to determine the, steady-state stability and transient characteristics of the engine under control at various altitudes and ram pressure ratios, without afterburning. Recordings of the response of the following parameters to step changes in power lever position throughout the available operating range of the engine were obtained; ram pressure ratio, compressor-discharge pressure, exhaust-nozzle area, engine speed, turbine-outlet temperature, fuel-valve position, jet thrust, air flow, turbine-discharge pressure, fuel flow, throttle position, and boost-pump pressure. Representative preliminary data showing the actual time response of these variables are presented. These data are presented in the form of reproductions of oscillographic traces.

Ketchum, James R.↗
NASA NTRS1973

Gas turbine engine fuel control

A variable orifice system is described that is responsive to compressor inlet pressure and temperature, compressor discharge pressure and rotational speed of a gas-turbine engine. It is incorporated into a hydraulic circuit that includes a zero gradient pump driven at a speed proportional to the speed of the engine. The resulting system provides control of fuel rate for starting, steady running, acceleration and deceleration under varying altitudes and flight speeds.

Gold, H. S.↗
NASA NTRS2013

Gear Design Effects on the Performance of High Speed Helical Gear Trains as Used in Aerospace Drive Systems

The performance of high-speed helical gear trains is of particular importance for tiltrotor aircraft drive systems. These drive systems are used to provide speed reduction/torque multiplication from the gas turbine output shaft and provide the necessary offset between these parallel shafts in the aircraft. Four different design configurations have been tested in the NASA Glenn Research Center, High Speed Helical Gear Train Test Facility. The design configurations included the current aircraft design, current design with isotropic superfinished gear surfaces, double helical design (inward and outward pumping), increased pitch (finer teeth), and an increased helix angle. All designs were tested at multiple input shaft speeds (up to 15,000 rpm) and applied power (up to 5,000 hp). Also two lubrication, system-related, variables were tested: oil inlet temperature (160 to 250 F) and lubricating jet pressure (60 to 80 psig). Experimental data recorded from these tests included power loss of the helical system under study, the temperature increase of the lubricant from inlet to outlet of the drive system and fling off temperatures (radially and axially). Also, all gear systems were tested with and without shrouds around the gears. The empirical data resulting from this study will be useful to the design of future helical gear train systems anticipated for next generation rotorcraft drive systems.

Handschuh, R.↗
NASA NTRS2013

Gear Design Effects on the Performance of High Speed Helical Gear Trains as Used in Aerospace Drive Systems

The performance of high-speed helical gear trains is of particular importance for tiltrotor aircraft drive systems. These drive systems are used to provide speed reduction / torque multiplication from the gas turbine output shaft and provide the necessary offset between these parallel shafts in the aircraft. Four different design configurations have been tested in the NASA Glenn Research Center, High Speed Helical Gear Train Test Facility. The design configurations included the current aircraft design, current design with isotropic superfinished gear surfaces, double helical design (inward and outward pumping), increased pitch (finer teeth), and an increased helix angle. All designs were tested at multiple input shaft speeds (up to 15,000 rpm) and applied power (up to 5,000 hp). Also two lubrication, system-related, variables were tested: oil inlet temperature (160 to 250 degF) and lubricating jet pressure (60 to 80 psig). Experimental data recorded from these tests included power loss of the helical system under study, the temperature increase of the lubricant from inlet to outlet of the drive system and fling off temperatures (radially and axially). Also, all gear systems were tested with and without shrouds around the gears. The empirical data resulting from this study will be useful to the design of future helical gear train systems anticipated for next generation rotorcraft drive systems.

Handschuh, R.↗
NASA NTRS1984

Analysis of inviscid and viscous flows in cascades with an explicit multiple-grid algorithm

A rapid technique is used for calculating inviscid and viscous flows in turbomachinery cascades. The Euler and thin-layer Navier-Stokes equations are solved using the original explicit MacCormack algorithm. The Baldwin-Lomax eddy viscosity model is used for turbulent flows. Convergence to a steady state is accelerated by use of a variable time-step and a multiple-grid scheme. Computer time is reduced through vectorization. Details of the numerical method are presented along with computed results for two low-speed wind tunnel turning vanes, a space shuttle fuel pump turbine rotor, and a supersonic inflow compressor rotor. The method can predict subtle viscous flow phenomena in cascades and is fast enough to be used as a design tool.

Chima, R. V.↗