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Test 1130: Deutz D 13006 Diesel, Nebraska Tractor Test Lab
Test 1130: Deutz D 13006 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 1133: Massey-Ferguson 1085 Diesel, Nebraska Tractor Test Lab
Test 1133: Massey-Ferguson 1085 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 1134: Massey-Ferguson 1155 Diesel, Nebraska Tractor Test Lab
Test 1134: Massey-Ferguson 1155 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 1136: David Brown 995 Diesel (Also Case 995 Diesel) 12-Speed, Nebraska Tractor Test Lab
Test 1136: David Brown 995 Diesel (Also Case 995 Diesel) 12-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 …
Test 1139: Belarus Mtz 80 Diesel, Nebraska Tractor Test Lab
Test 1139: Belarus Mtz 80 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 1146: John Deere 830 Diesel, Nebraska Tractor Test Lab
Test 1146: John Deere 830 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 1149: Case 870 Manual Diesel, Nebraska Tractor Test Lab
Test 1149: Case 870 Manual 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 1150: Case 870 Power Shift Diesel, Nebraska Tractor Test Lab
Test 1150: Case 870 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 …
Test 1151: International 666 And 686 Diesel, Nebraska Tractor Test Lab
Test 1151: International 666 And 686 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 1155: International Hydro 666, 70 And 86 Diesel, Nebraska Tractor Test Lab
Test 1155: International Hydro 666, 70 And 86 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 …
Nucleate Pool Boiling Of Refrigerant-Oil Mixtures From Tubes, R. L. Dougherty
Nucleate Pool Boiling Of Refrigerant-Oil Mixtures From Tubes, R. L. Dougherty
Masters Theses
"This experimental investigation was conducted to provide design heat transfer data for applications involving the nucleate pool boiling of Refrigerants 11 and 113 from the external surfaces of tubes. Tests were conducted with 0.625-in. o.d. and 1.125-in. o.d. commercial copper tubing; at 1 and 2 atmospheres pressure; and with refrigerant-oil compositions from 0 to 10 percent oil by weight. Results show that each of these parameters can affect the heat transfer coefficient"--Abstract, page ii.
Linear Stability Of Non-Parallel Flow In The Entrance Region Of Ducts, Francis Chung-Ti Shen
Linear Stability Of Non-Parallel Flow In The Entrance Region Of Ducts, Francis Chung-Ti Shen
Doctoral Dissertations
"An investigation is made of the linear stability of the developing flow of an incompressible fluid in the entrance region of annular ducts, circular tubes, and parallel-plate channels. Small axisymmetric disturbances for annular duct and tube flows and small two-dimensional disturbances for channel flow are considered in the analysis. In formulating the stability problems, account is taken of the transverse velocity component of the mainflow. This results in the modified Orr-Sommerfeld equations, one for annular duct and tube flows and the other for channel flow. The mainflow velocity fields utilized in the stability analysis are those from the solutions of …
Rock Fragmentation By Subsurface Thermal Inclusions - A Finite Element Study, Mahendrakumar Ramkrishna Patel
Rock Fragmentation By Subsurface Thermal Inclusions - A Finite Element Study, Mahendrakumar Ramkrishna Patel
Doctoral Dissertations
"Although rock tunneling machines are being used extensively with performance and cost advantages over traditional drill and blast methods, their usefulness for hard rock excavation is far from being practical due mainly to the inability of present day mechanical cutters to penetrate these rocks economically. Among various novel techniques that are being investigated, internal heating methods seem to be the most promising. This investigation is concerned with a feasibility study of thermal rock fragmentation using heat to create in-depth thermal inclusions.
The three-dimensional problem of in situ rock fragmentation involves parallel rows of equidistant holes drilled to a constant depth. …
Numerical Simulation Of Heat, Mass, And Momentum Transfer In An Atmospheric Boundary Layer, Darrell W. Pepper
Numerical Simulation Of Heat, Mass, And Momentum Transfer In An Atmospheric Boundary Layer, Darrell W. Pepper
Doctoral Dissertations
"Considerable interest has developed in recent years to understand transport phenomena in thermally stratified boundary layers. More complete knowledge in this field is needed to improve the prediction of the diffusion of air pollutants in the lower atmosphere as well as in forecasting air-water circulation for weather conditions.
The atmospheric boundary layer is modeled using the equations of continuity, momentum, energy, and concentration. Closure of this set of partial differential equations is hindered by the turbulence terms. Using turbulence kinetic energy, the system of equations is closed by internally determining the exchange coefficients of heat, mass, and momentum along with …
A Study Of The Dynamic Loading Of Hydrodynamically Lubricated Journal Bearings, Nader Khorzad
A Study Of The Dynamic Loading Of Hydrodynamically Lubricated Journal Bearings, Nader Khorzad
Doctoral Dissertations
"The analytical and experimental investigation presented here examined the response of a full journal bearing to a unidirectional dynamic load. Frequency response of the bearing at different eccentricity ratios was investigated. It was concluded that the response of the bearing varies with eccentricity. The experimental data obtained was compared to an analytical model which considered inertial, damping, and elastic characteristics of the lubricant film. An investigation of film pressure revealed that the pressure due to journal center acceleration is smaller than the hydrodynamic and squeeze-film pressures"--Abstract, page 1.
Experimental Analysis Of V-Belt Tensile Loads, John Mark Wiesehan
Experimental Analysis Of V-Belt Tensile Loads, John Mark Wiesehan
Masters Theses
"An experimental investigation was conducted to determine the magnitude of v-belt stresses in automotive drive situations. A constant tension belt test apparatus was designed and fabricated using a variable speed cradled D.C. motor for power and two automotive alternators for absorption.
Free span stresses on the dynamic torque loaded belt drive were determined from the equations governing a pivoted drive system. Centrifugal stress was determined by a theoretical analysis of belt motion. Bending stresses were obtained from a static test employing strain gages mounted on the top of belts with exposed cord layers. The variation in load stress around the …
Interior Noise In Military Helicopters, Charles E. Perez Jr.
Interior Noise In Military Helicopters, Charles E. Perez Jr.
Masters Theses
"The Temporary Threshold Shift (TTS) or temporary hearing loss caused by excessive interior noise in military helicopters results in a critical degradation of the acoustically unprotected infantryman's ability to detect the existence or the approach of the enemy by hearing under combat conditions. The overall problem of noise reduction in helicopters consists of: (1) identifying the various noise sources, and (2) employing appropriate noise control techniques. Identification of the source is accomplished by the frequency correlation of 1/10-octave band analysis of the interior sound levels measured within the helicopter cabin with near-field sound generated by the sound sources. Reduction of …
Analysis Of Interferometric Holography In Temperature Measurement, Allan James Reifel
Analysis Of Interferometric Holography In Temperature Measurement, Allan James Reifel
Masters Theses
"An experimental investigation was conducted to evaluate the accuracy and sensitivity of a laser holographic interferometer. Interference fringe patterns of a free convection boundary layer on the surface of a vertical test plate were produced. The plate was heated and designed to produce a linear temperature distribution along its surface.
A thermocouple probe was used to map the temperatures in the boundary layer and these values were compared to temperatures obtained from fringe patterns. Data photographs of the holograms were used in the analysis. The number of fringes obtained were compared to predictions of the Gladstone-Dale Law.
High quality fringe …
A Digital Simulation Of A Single Articulated Rotor Helicopter, Joseph William Klahs Jr.
A Digital Simulation Of A Single Articulated Rotor Helicopter, Joseph William Klahs Jr.
Masters Theses
"The investigation was concerned with the development of a complete digital computer simulation of a single articulated rotor helicopter. The simulation program was executed on an IBM model 360-50 digital computer.
The main rotor was analyzed by the consideration of a continuous rigid blade at six azimuth stations, while the airframe aerodynamics were treated in the conventional manner. The differential equations of motion of the airframe were solved in a step-wise fashion by approximating time dependent functions with cubic interpolation polynomials.
The study concluded that there was strong evidence that suggested the possibility of treating main rotor flapping as a …
Approximate Normal Mode Method To Determine The Response Of Certain Nondiagonalizabel Vibratory Systems, Jayaram Seshadri
Approximate Normal Mode Method To Determine The Response Of Certain Nondiagonalizabel Vibratory Systems, Jayaram Seshadri
Masters Theses
"An approximate normal mode method is developed which permits certain normally nondiagonalizable, nonconservative systems to be solved by superposition of uncoupled coordinates.
An approximate solution for a nonproportionally damped, multi-degree of freedom system is obtained by using a perturbation technique. The system is then reduced to a proportionally damped system by means of a modification to the damping factor so that the effect of the off-diagonal terms of the modal damping matrix is included. This modification produces a damping matrix that can be diagonalized by the normal mode technique. An approximate criterion is used for the determination of the modified …
Transient State Analysis Of Separated Flow Around A Sphere, Ching-Liang Lin
Transient State Analysis Of Separated Flow Around A Sphere, Ching-Liang Lin
Doctoral Dissertations
"Transient state solution of the Navier Stokes equation was obtained for incompressible flow around a sphere accelerating from zero initial velocity to its terminal free falling velocity. By assuming rotational symmetry around the axis in the falling direction, the Navier Stokes equation and the continuity equation were simplified in terms of vorticity and stream function. The instantaneous acceleration of the falling sphere was calculated by considering the difference between the gravitational force and the drag force in a transient state. The governing partial differential equations were non-dimensionalized. A set of implicit finite difference equations was developed. In order to obtain …
Stability Of The Developing Laminar Flow In A Circular Tube, Lung-Mau Huang
Stability Of The Developing Laminar Flow In A Circular Tube, Lung-Mau Huang
Doctoral Dissertations
"An investigation is made of the linear stability of the developing laminar flow of an incompressible fluid in the entrance region of a circular tube. Both axisymmetric and non-axisymmetric small disturbances are considered in the analysis. The stability characteristics of the fully developed flow are also re-examined. The main flow velocity distribution used in the stability analysis is that from the solution of the linearized momentum equation. The governing equations for the disturbances and the boundary conditions constitute an eigenvalue problem which is solved by a direct numerical integration scheme along with an iteration technique. The solution starts with a …
Methods For Predicting The Influence Of Intense Sound, Steady Flow, And Elevated Temperature On The Acoustic Performance Of Automotive Exhaust System Components, Richard Chuka Oboka
Methods For Predicting The Influence Of Intense Sound, Steady Flow, And Elevated Temperature On The Acoustic Performance Of Automotive Exhaust System Components, Richard Chuka Oboka
Doctoral Dissertations
"The principal objective of this investigation was to study the feasibility of developing laboratory techniques for automobile-exhaust muffler design in order to reduce the amount of on-vehicle trial-and-error testing currently required. The investigation included (1) improving the capability of existing laboratory equipment to simulate the conditions in automobile exhaust (i.e., high-amplitude pressure waves, steady flow, and elevated temperature), and (2) theoretical and experimental studies of typical acoustic elements (side-branch resonators, expansion chambers, louvered tubes) used in muffler design. The sound fields used for these studies included pure tones, single pulses (tone bursts), random noise, and simulated automobile exhaust noise.
Empirical …
Engineering And Scientific Manpower- A Scarce Resource For The 1970'S, Merl Baker
Engineering And Scientific Manpower- A Scarce Resource For The 1970'S, Merl Baker
Mechanical and Aerospace Engineering Faculty Research & Creative Works
No abstract provided.
Breakdown Of The Laminar Flow Regime In Permeable-Walled Ducts, E. M. Sparrow, G. S. Beavers, T. S. Chen, J. R. Lloyd
Breakdown Of The Laminar Flow Regime In Permeable-Walled Ducts, E. M. Sparrow, G. S. Beavers, T. S. Chen, J. R. Lloyd
Mechanical and Aerospace Engineering Faculty Research & Creative Works
The stability of laminar flow in a parallel-plate channel having one permeable bounding wall is investigated by means of linear theory. The analysis lakes account of the coupling of the disturbance, fields in the channel and in the permeable material and of velocity slip at the surface of the permeable wall. Complementary experiments are performed in which the breakdown of the laminar regime in flat rectangular ducts is identified from pressure-drop measurements and from flow visualization studies. The experiments cover the range of slip velocities from 15-30 percent of the mean velocity and, in addition, the case of zero slip …
On The Complex Index Of Refraction Of Bulk Materials, Carol Jeanne Warren
On The Complex Index Of Refraction Of Bulk Materials, Carol Jeanne Warren
Masters Theses
"As a part of the investigation of classical reflectance, it is determined that the hemispherical reflectance for a material with a particular pair of optical constants can be approximated by computing the angular reflectance at sixty degrees, using Fresnel's generalized reflectance formulas.
Reflection methods for the purpose of determining the optical constants of a variety of materials are discussed. The unpolarized reflectance versus angle of incidence technique is used for determination of the optical constants of bulk solids. Restrictions on the simultaneous solution of the Fresnel equations are determined and a computer program is developed to compute values necessary to …
Nebraska Tractor Test 1110 John Deere 4430 Quad -Range Diesel, Nebraska Tractor Test Lab
Nebraska Tractor Test 1110 John Deere 4430 Quad -Range Diesel, Nebraska Tractor Test Lab
Nebraska Tractor Tests
All lest result s were determined from observed data obtained in accordance with SAE and ASAE test code or official Nebraska test procedure. First and second gears were not run as it was necessary to limit the pull in third gear to avoid excessive slippage. Fourth, tenth, eleventh, twelfth, thirteenth, fourteenth , fifteenth and sixteenth gears were not run as test procedure requires only six travel speeds. During maximum drawbar run in 3rd gear the transmission came out of gear twice making it necessary to hold the shift lever in place to complete the run.
Peak Temperature Distribution In Steel Plates During Arc-Welding, Bhanuprakash M. Patel
Peak Temperature Distribution In Steel Plates During Arc-Welding, Bhanuprakash M. Patel
Theses and Dissertations
The welding of steel plays an important role as a major fabricating process in industry. In the field of welding metallurgy, much attention is given to the effects which a welding arc or flame will have on the structure and properties of the metals being joined. The engineer is interested in the intensify and extent of physical changes brought about by the unavoidable heat treatment which accompanies the execution of a weld. In order to gain some quantitative appreciation of the way in which the metallurgical effects of welding depend on welding variables, geometry, and physical properties, considerable attention has …
Rotary Engine Designs Based On A Particular Off-Set Cavity/Rotor System, M. Dean Black
Rotary Engine Designs Based On A Particular Off-Set Cavity/Rotor System, M. Dean Black
Theses and Dissertations
The subject of this thesis is a family of rotary engines, each consisting of a two-tipped rotor turning about an off-center axis within a nearly round cavity.
The Creep And Stress Relaxation Behavior Of Silver Bearing Copper Wire, Alfred Fox
The Creep And Stress Relaxation Behavior Of Silver Bearing Copper Wire, Alfred Fox
Theses
Creep and stress-relaxation experiments were performed on silverless and silver bearing copper in the temperature range 73F to 250F. The creep experiments were conducted at constant load and temperature, the stress-relaxation tests at constant total strain and temperature for a total time period of 1000 hours. The effect of silver addition of up to 0.2 percent w/o (60oz per ton) on the creep and stress-relaxation behavior of spectrographically pure copper (99.999+ Cu) as well as on that of tough pitch and oxygen free coppers of lesser purity was studied. Spectrographically pure copper was found to be much more susceptible to …