States

The effects of engine speed and mixture temperature on the knocking characteristics of several fuels (open access)

The effects of engine speed and mixture temperature on the knocking characteristics of several fuels

Six 100-octane and two 87-octane aviation engine fuels were tested in a modified C.F.R. variable-compression engine at 1,500, 2,000 and 2,500 rpm. The mixture temperature was raised from 50 to 300 F in approximately 50 degree steps and, at each temperature, the compression ratio was adjusted to give incipient knock as shown by a cathode ray indicator. The results are presented in tabular form. The results are analyzed on the assumption that the conditions which determine whether a given fuel will knock are the maximum values of density and temperature reached by the burning gases. A maximum permissible density factor, proportional to the maximum density of the burning gases just prior to incipient knock, and the temperature of the burning gases at that time were computed for each of the test conditions. Values of the density factors were plotted against the corresponding end-gas temperatures for the three engine speeds and also against engine speed for several and end-gas temperatures. The maximum permissible density factor varied only slightly with engine speed but decreased rapidly with an increase in the end-gas temperature. The effect of changing the mixture temperature was different for fuels of different types. The results emphasize the desirability of …
Date: July 1940
Creator: Lee, Dana W.
Object Type: Report
System: The UNT Digital Library
Apple Growing East of the Mississippi River. (open access)

Apple Growing East of the Mississippi River.

Describes the various factors that should be taken into consideration when developing and maintaining apple orchards, including: types of soil, climate conditions, the selecting and handling of young trees, the use of fertilizers, methods of pruning and spraying, and methods of repelling pests.
Date: July 1940
Creator: Gould, H. P.
Object Type: Book
System: The UNT Digital Library
Production of Peppers (open access)

Production of Peppers

Describes the characteristics of peppers, lists the different varieties, and the steps necessary to successfully produce quality peppers.
Date: July 1940
Creator: Beattie, James H. (James Herbert), b. 1882; Doolittle, S. P. (Sears Polydore), 1890-1961; Beattie, W. R. (William Renwick), b. 1870 & Magruder, Roy, 1900-
Object Type: Book
System: The UNT Digital Library
Heat Transfer Tests of a Steel Cylinder Barrel With Aluminum Fins With Improved Bonding Between Steel Barrel and Aluminum Base (open access)

Heat Transfer Tests of a Steel Cylinder Barrel With Aluminum Fins With Improved Bonding Between Steel Barrel and Aluminum Base

Report presenting testing of a steel cylinder barrel with aluminum fins in order to evaluate the effect of using preformed aluminum fins on a steel barrel or aluminum barrel. Results regarding the heat-transfer tests and physical tests are provided.
Date: July 1940
Creator: Ellerbrock, Herman H., Jr.
Object Type: Report
System: The UNT Digital Library
Experimental Investigation to Determine the Relative Magnitude of Vertical and Horizontal Gusts in the Atmosphere (open access)

Experimental Investigation to Determine the Relative Magnitude of Vertical and Horizontal Gusts in the Atmosphere

Report presenting an investigation to obtain data on the vertical and horizontal gusts in the atmosphere by reworking accelerometers and airspeed records from past investigations of vertical gusts. The results indicate that the vertical and horizontal gusts are of about equal intensity in the atmosphere.
Date: July 1940
Creator: Donely, Philip
Object Type: Report
System: The UNT Digital Library
Monthly Report of the Attorney General of the State of Texas, Volume 2, Number 6, June 1940 (open access)

Monthly Report of the Attorney General of the State of Texas, Volume 2, Number 6, June 1940

Monthly report documenting orders, opinions, and other legal statements issued by the Office of the Attorney General in Texas.
Date: July 1940
Creator: Texas. Attorney-General's Office.
Object Type: Report
System: The Portal to Texas History
Preparing Wool for Market. (open access)

Preparing Wool for Market.

Provides instructions for shearing a sheep and preparing the wool for market.
Date: July 1940
Creator: Buck, Warner M. (Warner Mays), 1892-
Object Type: Book
System: The UNT Digital Library
U.S. Graded and Stamped Meat. (open access)

U.S. Graded and Stamped Meat.

Describes the official grades for beef, lamb and mutton, and veal and calf. Provides charts of meat cuts.
Date: July 1940
Creator: United States. Agricultural Marketing Service.
Object Type: Book
System: The UNT Digital Library
Propeller analysis from experimental data (open access)

Propeller analysis from experimental data

The operation of the propeller is analyzed by the use of the distribution of forces along the radius, combined with theoretical equations. The data were obtained in the NACA 20-foot wind tunnel on a 4-foot-diameter, two-blade propeller, operating in front of four body shapes, ranging from a small shaft to support the propeller to conventional NACA cowling. A method of estimating the axial and the rotational energy in the wake as a fractional part of the propeller power is given. A knowledge of the total thrust and torque is necessary for the estimation.
Date: July 19, 1940
Creator: Stickle, George W. & Crigler, John L.
Object Type: Report
System: The UNT Digital Library
A high-speed motion-picture study of normal combustion, knock and preignition in a spark-ignition engines (open access)

A high-speed motion-picture study of normal combustion, knock and preignition in a spark-ignition engines

Combustion in a spark-ignition engine was investigated by means of the NACA high-speed motion-picture cameras. This camera is operated at a speed of 40,000 photographs a second and therefore makes possible the study of changes that take place in the intervals as short as 0.000025 second. When the motion pictures are projected at the normal speed of 16 frames a second, any rate of movement shown is slowed down 2500 times. Photographs are presented of normal combustion, of combustion from preignitions, and of knock both with and without preignition. The photographs of combustion show that knock may be preceded by a period of exothermic reaction in the end zone that persists for a time interval of as much as 0.0006 second. The knock takes place in 0.00005 second or less.
Date: July 24, 1940
Creator: Rothrock, A. M.; Spencer, R. C. & Miller, Cearcy D.
Object Type: Report
System: The UNT Digital Library
New Equipment for Testing the Fatigue Strength of Riveted and Welded Joints (open access)

New Equipment for Testing the Fatigue Strength of Riveted and Welded Joints

"The mechanical and electrical construction of a new experimental instrument for fatigue testing riveted and welded joints is described. This experimental device has the advantage of being able to stress, even with comparatively low magnetic exciter force, structural components in alternate bending by resonance vibrations up to incipient fatigue failure (p .1)".
Date: July 1940
Creator: Müller, W.
Object Type: Report
System: The UNT Digital Library
Experimental Results With Airfoils Tested in the High-Speed Tunnel at Guidonia (open access)

Experimental Results With Airfoils Tested in the High-Speed Tunnel at Guidonia

The results are presented of a triple series of tests using force measurements, pressure-distribution measurements, and air flow photographs on airfoil sections suitably selected so that comparison could be made between the experimental and theoretical results. The comparison with existing theory is followed by a discussion of the divergences found, and an attempt is made to find their explanation.
Date: July 1940
Creator: Ferri, Antonio
Object Type: Report
System: The UNT Digital Library
Experiments on Ball and Roller Bearings Under Conditions of High Speed and Small Oil Supply (open access)

Experiments on Ball and Roller Bearings Under Conditions of High Speed and Small Oil Supply

This report describes a testing machine on which 35 millimeter bearings (bore) can be run at speeds of the order of 21,000 rpm, while the following factors are recorded: 1) oil circulation through bearing and oil temperature. 2) maximum temperature of outer bearing ring, 3) radial and axial load on bearing, 4) radial, axial, and angular clearance of bearing, 5) power consumption of bearing. The experiments show that the lubrication was most reliable and oil consumption lowest when the oil was introduced through a hole in the outer or inner ring of the bearing.
Date: July 1940
Creator: Getzlaff, Günter
Object Type: Report
System: The UNT Digital Library
Texas Business Review, Volume 14, Issue 6, July 1940 (open access)

Texas Business Review, Volume 14, Issue 6, July 1940

Newsletter of the University of Texas Bureau of Business Research outlining statistics and research related to business in Texas.
Date: July 27, 1940
Creator: University of Texas. Bureau of Business Research.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History