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Articles 28291 - 28320 of 30020
Full-Text Articles in Engineering
Test 1112: John Deere 4230 Quad-Range Diesel, Nebraska Tractor Test Lab
Test 1112: John Deere 4230 Quad-Range Diesel, Nebraska Tractor Test Lab
Nebraska Tractor Tests
EXPLANATION OF TEST REPORT
GENERAL CONDITIONS
East tractor is a production model equipped for common usage. Power consuming accessories can be disconnected only when it is convenient for the operator to do so in practice. Additional weight can be added as ballast if the manufacturer regularly supplies it for sale. The static tire loads and the inflation pressures muse conform to recommendations in the Tire Standards published by the Society of Automotive Engineers.
PREPARATION FOR PERFORMANCE RUNS
The engine crank case is drained and refilled with a measured amount of new oil conforming to specifications in the operator’s manual. The …
Test 1115: International 354 Gasoline 8-Speed, Nebraska Tractor Test Lab
Test 1115: International 354 Gasoline 8-Speed, Nebraska Tractor Test Lab
Nebraska Tractor Tests
EXPLANATION OF TEST REPORT
GENERAL CONDITIONS
East tractor is a production model equipped for common usage. Power consuming accessories can be disconnected only when it is convenient for the operator to do so in practice. Additional weight can be added as ballast if the manufacturer regularly supplies it for sale. The static tire loads and the inflation pressures muse conform to recommendations in the Tire Standards published by the Society of Automotive Engineers.
PREPARATION FOR PERFORMANCE RUNS
The engine crank case is drained and refilled with a measured amount of new oil conforming to specifications in the operator’s manual. The …
Measurement Of Turbulence In An Annular Jet, George Philip
Measurement Of Turbulence In An Annular Jet, George Philip
Masters Theses
"An experimental investigation was conducted for an annular jet which consisted of a circular jet and a concentric wake. The annular air jet mixed with quiescent atmospheric air. The jet velocity was kept constant at 137.0 feet per second which corresponds to a Reynolds Number of 73,200. Using the technique of hot-wire anemometry, mean velocities, turbulence intensities and Reynolds stresses were measured in the longitudinal and lateral directions. Two distinct flow regimes, the free stream jet regime and the diffusing jet regime, are observed. In the free stream jet regime, higher turbulence intensity and shear stress occur in the inner …
Test 1105: Deutz D100 06 Diesel, Nebraska Tractor Test Lab
Test 1105: Deutz D100 06 Diesel, Nebraska Tractor Test Lab
Nebraska Tractor Tests
EXPLANATION OF TEST REPORT
GENERAL CONDITIONS
East tractor is a production model equipped for common usage. Power consuming accessories can be disconnected only when it is convenient for the operator to do so in practice. Additional weight can be added as ballast if the manufacturer regularly supplies it for sale. The static tire loads and the inflation pressures muse conform to recommendations in the Tire Standards published by the Society of Automotive Engineers.
PREPARATION FOR PERFORMANCE RUNS
The engine crank case is drained and refilled with a measured amount of new oil conforming to specifications in the operator’s manual. The …
Test 1106: Satoh S650g Gasoline (Also Bison Gasoline), Nebraska Tractor Test Lab
Test 1106: Satoh S650g Gasoline (Also Bison Gasoline), Nebraska Tractor Test Lab
Nebraska Tractor Tests
EXPLANATION OF TEST REPORT
GENERAL CONDITIONS
East tractor is a production model equipped for common usage. Power consuming accessories can be disconnected only when it is convenient for the operator to do so in practice. Additional weight can be added as ballast if the manufacturer regularly supplies it for sale. The static tire loads and the inflation pressures muse conform to recommendations in the Tire Standards published by the Society of Automotive Engineers.
PREPARATION FOR PERFORMANCE RUNS
The engine crank case is drained and refilled with a measured amount of new oil conforming to specifications in the operator’s manual. The …
Test 1113: John Deere 4630 Power Shift Diesel, Nebraska Tractor Test Lab
Test 1113: John Deere 4630 Power Shift Diesel, Nebraska Tractor Test Lab
Nebraska Tractor Tests
EXPLANATION OF TEST REPORT
GENERAL CONDITIONS
East tractor is a production model equipped for common usage. Power consuming accessories can be disconnected only when it is convenient for the operator to do so in practice. Additional weight can be added as ballast if the manufacturer regularly supplies it for sale. The static tire loads and the inflation pressures muse conform to recommendations in the Tire Standards published by the Society of Automotive Engineers.
PREPARATION FOR PERFORMANCE RUNS
The engine crank case is drained and refilled with a measured amount of new oil conforming to specifications in the operator’s manual. The …
Reply To The Comments Of H. M. Princen [2], Robert A. Medrow, B. T. Chao
Reply To The Comments Of H. M. Princen [2], Robert A. Medrow, B. T. Chao
Mechanical and Aerospace Engineering Faculty Research & Creative Works
No abstract provided.
Forming Of 7075-T6 Aluminum In High Pressure Environments, Richard L. Pendleton, Robert L. Davis
Forming Of 7075-T6 Aluminum In High Pressure Environments, Richard L. Pendleton, Robert L. Davis
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Plates of 7075-T6 Aluminum have been folded along a major axis in pressure environments of atmospheric, 20,000 psi, and 40,000 psi. A finite element computer program is used to determine the stress state in the plates at various loads. Tension and compression tests conducted in pressure environments up to 70,000 psi were used to construct models using effective stress, effective strain, and pressure as parameters to predict the behavior of the material under various stress conditions. A prediction of the occurrence of fracture in the folded plate was possible using the computer results and the pressure dependent model. As better …
The Analog Simulation Of Heat Transfer Devices For The Smoothing Of A Fluctuating Fluid Temperature, Le Thai Son
The Analog Simulation Of Heat Transfer Devices For The Smoothing Of A Fluctuating Fluid Temperature, Le Thai Son
Masters Theses
"Equations are written to describe a heat exchanger with electrical energy input and also a large tank system which can have electrical energy input. The output temperatures were sampled and fedback to define the energy input to the two systems. These systems were simulated on an analog computer and the ability of the two systems to smooth a fluctuating temperature input was tested. The testing of the systems included trying different types of controllers in the control system as well as different size tanks for the tank system. A satisfactory smoothing of the output temperature was demonstrated after some modifications"--Abstract, …
Test 1117: International Farmall 766 Diesel 16-Speed (Chassis S/N 2490180u009000 And Up), Nebraska Tractor Test Lab
Test 1117: International Farmall 766 Diesel 16-Speed (Chassis S/N 2490180u009000 And Up), Nebraska Tractor Test Lab
Nebraska Tractor Tests
EXPLANATION OF TEST REPORT
GENERAL CONDITIONS
East tractor is a production model equipped for common usage. Power consuming accessories can be disconnected only when it is convenient for the operator to do so in practice. Additional weight can be added as ballast if the manufacturer regularly supplies it for sale. The static tire loads and the inflation pressures muse conform to recommendations in the Tire Standards published by the Society of Automotive Engineers.
PREPARATION FOR PERFORMANCE RUNS
The engine crank case is drained and refilled with a measured amount of new oil conforming to specifications in the operator’s manual. The …
Test 1114: Case 2470 Diesel, Nebraska Tractor Test Lab
Test 1114: Case 2470 Diesel, Nebraska Tractor Test Lab
Nebraska Tractor Tests
EXPLANATION OF TEST REPORT
GENERAL CONDITIONS
East tractor is a production model equipped for common usage. Power consuming accessories can be disconnected only when it is convenient for the operator to do so in practice. Additional weight can be added as ballast if the manufacturer regularly supplies it for sale. The static tire loads and the inflation pressures muse conform to recommendations in the Tire Standards published by the Society of Automotive Engineers.
PREPARATION FOR PERFORMANCE RUNS
The engine crank case is drained and refilled with a measured amount of new oil conforming to specifications in the operator’s manual. The …
Test 1092: Duetz D130 06 Diesel, Nebraska Tractor Test Lab
Test 1092: Duetz D130 06 Diesel, Nebraska Tractor Test Lab
Nebraska Tractor Tests
EXPLANATION OF TEST REPORT
GENERAL CONDITIONS
East tractor is a production model equipped for common usage. Power consuming accessories can be disconnected only when it is convenient for the operator to do so in practice. Additional weight can be added as ballast if the manufacturer regularly supplies it for sale. The static tire loads and the inflation pressures muse conform to recommendations in the Tire Standards published by the Society of Automotive Engineers.
PREPARATION FOR PERFORMANCE RUNS
The engine crank case is drained and refilled with a measured amount of new oil conforming to specifications in the operator’s manual. The …
Test 1109: Long U-550 And U-560 Diesel (Also Utb U-550 Diesel), Nebraska Tractor Test Lab
Test 1109: Long U-550 And U-560 Diesel (Also Utb U-550 Diesel), Nebraska Tractor Test Lab
Nebraska Tractor Tests
EXPLANATION OF TEST REPORT
GENERAL CONDITIONS
East tractor is a production model equipped for common usage. Power consuming accessories can be disconnected only when it is convenient for the operator to do so in practice. Additional weight can be added as ballast if the manufacturer regularly supplies it for sale. The static tire loads and the inflation pressures muse conform to recommendations in the Tire Standards published by the Society of Automotive Engineers.
PREPARATION FOR PERFORMANCE RUNS
The engine crank case is drained and refilled with a measured amount of new oil conforming to specifications in the operator’s manual. The …
Test 1095: International Farmall 966 Hydro Diesel, Nebraska Tractor Test Lab
Test 1095: International Farmall 966 Hydro Diesel, Nebraska Tractor Test Lab
Nebraska Tractor Tests
EXPLANATION OF TEST REPORT
GENERAL CONDITIONS
East tractor is a production model equipped for common usage. Power consuming accessories can be disconnected only when it is convenient for the operator to do so in practice. Additional weight can be added as ballast if the manufacturer regularly supplies it for sale. The static tire loads and the inflation pressures muse conform to recommendations in the Tire Standards published by the Society of Automotive Engineers.
PREPARATION FOR PERFORMANCE RUNS
The engine crank case is drained and refilled with a measured amount of new oil conforming to specifications in the operator’s manual. The …
An Engineering Analysis Of Fluid Amplifiers And Development Of An Air Velocity Sensor, Gian Sagar Aneja
An Engineering Analysis Of Fluid Amplifiers And Development Of An Air Velocity Sensor, Gian Sagar Aneja
Masters Theses
"Fluidics, the new control technique finds its use amongst the conventional electronics and pneumatics due to some of its impressive features. Selected literature about bistable and proportional amplifiers has been presented for better understanding of the element behavior. Sensors; typical applications of fluidics have been described separately. An air flow velocity sensor has been set-up. Basically it consists of a cylinder placed across the air flow that sheds vortices in the wake due to 'Von Karman Vortex Street' phenomenon. The frequency of vortices gives a measure of velocity. The velocities obtained from the sensor have been compared to the ones …
The Steady-State Response Of A Fluid-Filled Beam Near Resonance, Niranjan Jayantibhai Patel
The Steady-State Response Of A Fluid-Filled Beam Near Resonance, Niranjan Jayantibhai Patel
Masters Theses
"In this report the steady-state near-resonant vibration of a hollow fluid-filled beam is considered. The energy dissipation caused by the beam-fluid interaction is approximated by introducing a viscous damping force into the Bernoulli-Euler beam equation. A theoretical expression is developed for the displacement of the hollow beam by solving this modified Bernoulli-Euler beam equation. Tests are made using a cantilevered fluid-filled box to simulate a unit of beam-fluid length. The band-width technique is used to determine the incremental viscous damping coefficient from test data. A variety of fluids are used in the box to determine the effect of the fluid …
Wind Tunnel Modeling Of The Atmospheric Boundary Layer, Sreemanth Pagadala
Wind Tunnel Modeling Of The Atmospheric Boundary Layer, Sreemanth Pagadala
Masters Theses
"The importance of simulating atmospheric flows in wind tunnels has been well established. Experiments were conducted in the Modified Aerodynamic Wind Tunnel to determine the suitability of this wind tunnel for simulating atmospheric flows and the degree to which various aspects of modeling could be fulfilled. A temperature profile to simulate the inversion aloft was generated inside the test section, and then an appropriate velocity profile was built in by means of screen mesh arrangements. The turbulence characteristics of the flow were measured. The validity of the temperature, velocity and turbulence fields were examined. It was found that while the …
Investigation Of A New Type Of Cloud Condensation Nuclei Counter: The Thermal Quench Chamber, Donald Arthur Hess
Investigation Of A New Type Of Cloud Condensation Nuclei Counter: The Thermal Quench Chamber, Donald Arthur Hess
Masters Theses
"The design and development of a new type of cloud condensation nuclei counter was undertaken to provide a new laboratory and field instrument that operates on a different theoretical basis than the thermal diffusion chamber now being used by meteorologists and other scientists. In the new instrument the test aerosol is pumped through a tube where it is first humidified and then cooled at constant pressure to create a supersaturation, causing water vapor to condense upon the nuclei in the aerosol sample. The concentration of cloud condensation nuclei is then determined by counting the water drops. The control of temperature …
Transient Cooling Of A Sphere Due To Boiling, Salil K. Banerjee
Transient Cooling Of A Sphere Due To Boiling, Salil K. Banerjee
Masters Theses
"The time - dependent surface temperature is determined for a sphere subjected to cooling by boiling. One dimensional heat transfer is considered and the solid is assumed to be homogeneous, isotropic and opaque to thermal radiation and to have temperature independent physical properties. The initial temperature of the sphere and the coolant are assumed to be uniform and arbitrary. The boiling heat transfer coefficient at the surface of a sphere is a strong function of the surface temperature thus resulting in an extremely nonlinear transient heat conduction problem. As a practical application of the problem, the process of quenching has …
A Practical Approach To The Exhaust Silencing Of A Pneumatic Rock Drill, Morton Gary Barth
A Practical Approach To The Exhaust Silencing Of A Pneumatic Rock Drill, Morton Gary Barth
Masters Theses
"One-third octave spectrum analyses of the exhaust noise produced by a medium sized pneumatic rock drill were obtained during free recriprocation to determine the most troublesome bands of noise. Noise reduction techniques were then used to design exhaust mufflers which would reduce the level of the exhaust noise to an acceptable level with a minimum increase in back pressure. The prototype mufflers evaluated included an expansion chamber, a resonator, and various modified expansion chambers. One of the modified expansion chambers tested provided very good attenuation reducing the exhaust noise from 113 dBA to 87 dBA at the operator's ear position. …
Application Of Transmission Matrices To Describe Transverse Vibrations Of Non-Uniform Bernoulli-Euler Beams, Dean Irle Parker
Application Of Transmission Matrices To Describe Transverse Vibrations Of Non-Uniform Bernoulli-Euler Beams, Dean Irle Parker
Masters Theses
"This report investigates the application of transmission Matrices to determine natural frequencies of non-uniform Bernoulli-Euler beams. The classes of non-uniform beams considered includes: truncated wedges, truncated cones, and truncated rectangular pyramids. Two transmission matrices were derived from solutions to the Bernoulli-Euler equation. One was an exact closed form solution which was applicable for the above classes of beams excluding uniform and nearly uniform beams. The second solution was an approximate one limited to the use for nearly uniform beams, but which does give the correct solution to the uniform beam in the limiting case. The transmission matrix has two advantages: …
Drift Velocity Measurements Of Various Materials Floating On Water Waves, Paul Keith Scherrer
Drift Velocity Measurements Of Various Materials Floating On Water Waves, Paul Keith Scherrer
Masters Theses
"A study was conducted to determine the affects of deep water gravity waves on oil lenses and surface floats. The experiment was conducted in a wave tank equipped with a mechanical wave generator. The data obtained consisted of the measured velocities of oil lenses and thin plastic floats under the action of a variety of wave conditions. It was found that waves do cause a movement of the oil lenses and surface floats, and their velocity was found to be greater than the surface drift predicted by Stokes' theory of mass transport by waves in a single component fluid. For …
On The Complex Index Of Refraction For Liquids, Juan Guillermo Ochoa Sierra
On The Complex Index Of Refraction For Liquids, Juan Guillermo Ochoa Sierra
Masters Theses
"Methods for determining the optical constants, the real and the imaginary part of the complex index of refraction, for weakly and strongly absorbing liquids are reviewed and evaluated. Both reflection and transmission methods were considered and preliminary steps are taken for determining the optical constants for both water and oil in the visible region (0.45 - 0.65 microns) of the spectrum. A low resolution spectrometer was used and the transmission measurements through fuel oil, number 1 through 6, and crude oil were performed. The imaginary part of the complex index of refraction was deduced from the above measurements and appears …
Feasibility Study Of Using A Steam Power System In A Small Garden Tractor, Niranjan Kumar Doshi
Feasibility Study Of Using A Steam Power System In A Small Garden Tractor, Niranjan Kumar Doshi
Masters Theses
"This thesis is a feasibility study of using a steam power system in a small garden tractor. The relative advantages of steam power are discussed and compared with the characteristics of internal combustion engines. A monotube boiler is designed where steam is generated in stacked tube spirals. The boiler generates 225 lbs/hr of dry saturated steam at 500 psia, which corresponds to an engine output of 20 IHpage A rotary positive displacement engine is employed to expand the steam to 16 psia. A rotor instead of a piston eliminates the conventional connecting rod and crank shaft. The engine developes 15 …
Design And Test An Operational Amplifier Speed Transducer, Tung-Ming Huang
Design And Test An Operational Amplifier Speed Transducer, Tung-Ming Huang
Masters Theses
"This thesis describes the design of an angular speed transducer. The purpose of this device is to provide a D.C. voltage which is proportional to the angular speed of a rotating shaft at any instant. The speed of the shaft is defined from a magnetic pickup monitoring a gear or similar device attached to the end of the shaft of a piece of rotating equipment. The signal from the magnetic pickup is modified and compared to a frequency generated in the feedback loop of the speed transducer and the error is sent to an integral type controller. The output of …
Analysis Of A Substitute For The Impact Damper To Damp Near-Resonant Mechanical Vibrations, Nguyen Khanh Van
Analysis Of A Substitute For The Impact Damper To Damp Near-Resonant Mechanical Vibrations, Nguyen Khanh Van
Masters Theses
"This report investigates a substitute for the impact damper which, although highly effective in reducing vibration amplitudes of near-resonant mechanical systems, in operation causes often unacceptable intensive noise. The present damper consists of a piston free to move in a cylinder, at either end of which is a ball valve set to open at a preset pressure, and in the middle along its length an intake port. An approximate analytical study is made to determine the conditions for the existence of "noiseless periodic operation" of the damper, periodic operation without the occurence of impacts. This approach is based on the …
Design Of A Torsional Vibration Machine, Prafulchandra Pragjibhai Desai
Design Of A Torsional Vibration Machine, Prafulchandra Pragjibhai Desai
Masters Theses
"In this thesis the design of the major components of a torsional vibration machine is presented. The machine is a torsional vibration actuator which will deliver a mean output angular velocity with a superimposed harmonic component. This type of motion can be used to study the torsional vibration characteristics of models representing crankshafts, gear trains, torsional dampers, and other systems. The primary machine elements of the actuator are a power source, flywheel, and a Hooke's joint. The power source consists of a D.C. shunt motor and a drive transmission using 3 V-belts. Through the use of a Hooke's joint, approximate …
The Effects Of Intense Sound Levels And Steady Flow On The Propagation Of Plane-Waves In Air, Wuu Hao
The Effects Of Intense Sound Levels And Steady Flow On The Propagation Of Plane-Waves In Air, Wuu Hao
Masters Theses
"This thesis is a theoretical investigation of the effects of intense sound levels and steady flow on the propagation of plane-waves in tubes of constant diameter. The analysis is limited to a study of the change of wave profile due to the intense sound levels, and steady flow. However, corrections for effects of viscous and heat conduction losses at tube walls are also presented. To simplify the analysis, the problem is treated by considering the steady flow and finite-amplitude-sound wave effects separately. For finite-amplitude sound only, two approaches are evaluated. The first uses small perturbations to derive a finite-amplitude wave …
Force Analysis Of Involute Spur Gears, Janakkumar Girjashanker Dave
Force Analysis Of Involute Spur Gears, Janakkumar Girjashanker Dave
Masters Theses
"This study is devoted to the fundamental action which occurs between spur gears with involute tooth profiles when power is transmitted at a constant angular velocity ratio. Various aspects of the interaction between two mating teeth are considered. Analytic expressions for the variation of the force transmitted between two teeth are derived. Two cases are considered which include and exclude the effects of sliding friction between the teeth. The parametric equations of the involute curves for two mating teeth are derived in terms of body-fixed coordinates. Analytical expressions for Hertz compressive stresses in the teeth were also obtained. The same …
A Study Of Plane Wave Filter Analysis With Flow, Thomas Valle Huber
A Study Of Plane Wave Filter Analysis With Flow, Thomas Valle Huber
Masters Theses
"The purpose of this investigation is to determine the effect of slow steady flow on the reflection and transmission characteristics of acoustic filters.
A standing wave tube and transmission tube apparatus, designed and built by a previous investigator, was modified to accept slow steady flow. Reflection characteristics were determined from measurements made on the inlet side of the filters investigated. These data along with measurements taken with the transmission tube apparatus were used to determine transmission characteristics. The calculations were simplified by terminating the filters anechoically. The filters used in this investigation were an expansion chamber, an automobile type muffler …