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Investigation of Air Flow in Open-Throat Wind Tunnels

Description: "Tests were conducted on the 6-inch wind tunnel of the National Advisory Committee for Aeronautics to form a part of a research on open-throat wind tunnels. The primary object of this part of the research was to study a type of air pulsation which has been encountered in open-throat tunnels, and to find the most satisfactory means of eliminating such pulsations. In order to do this it was necessary to study the effects of different variable on all of the important characteristics of the tunnel"… more
Date: September 26, 1928
Creator: Jacobs, Eastman N.
open access

Experimental and analytical determination of the motion of hydraulically operated valve stems in oil engine injection systems

Description: This research on the pressure variations in the injection system of the N.A.C.A. Spray Photography Equipment and on the effects of these variations on the motion of the timing valve stem was undertaken in connection with the study of fuel injection systems for high-speed oil engines. The methods of analysis of the pressure variations and the general equation for the motion of the spring-loaded stem for the timing valve are applicable to a spring-loaded automatic injection valve, and in general … more
Date: December 26, 1928
Creator: Gelalles, A. G. & Rothrock, A. M.
open access

The NACA Apparatus for Studying the Formation and Combustion of Fuel Sprays and the Results From Preliminary Tests

Description: "This report describes the apparatus as designed and constructed at the Langley Memorial Aeronautical Laboratory, for studying the formation and combustion of fuel sprays under conditions closely simulating those occurring in a high-speed compression-ignition engine. The apparatus consists of a single-cylinder modified test engine, a fuel-injection system so designed that a single charge of fuel can be injected into the combustion chamber of the engine, an electric driving motor, and a high-spe… more
Date: August 26, 1931
Creator: Rothrock, A. M.
open access

The drag of two streamline bodies as affected by protuberances and appendages

Description: This report presents the results of wind tunnel tests of two airship models conducted to determine the drag coefficients at zero pitch, and the effect of fins and cars and of flat and streamlined protuberances located at various positions along the hull. During the investigation the stern of one model was rounded off to produce a blunter shape. The extreme range of the Reynolds number based on the over-all length of the models was from 1,300,000 to 33,000,000. At large values of the Reynolds nu… more
Date: September 26, 1932
Creator: Abbott, Ira H.
open access

Tests of Nacelle-Propeller Combinations in Various Positions with Reference to Wings 5: Clark Y Biplane Cellule - NACA Cowled Nacelle - Tractor Propeller

Description: "This report is the fifth of a series giving the results obtained from wind tunnel tests on the interference drag and propulsive efficiency of nacelle-propeller-wing combinations. This report gives results of tests of an NACA cowled air-cooled engine nacelle with tractor propeller located in 12 positions with reference to a Clark Y biplane cellule" (p. 603).
Date: January 26, 1934
Creator: Valentine, E. Floyd
open access

Heat transfer from finned metal cylinders in an air stream

Description: This report presents the results of tests made to supply design information for the construction of metal fins for the cooling of heated cylindrical surfaces by an air stream. A method is given for determining fin dimensions for a maximum heat transfer with the expenditure of a given amount of material for a variety of conditions of air flow and metals.
Date: April 26, 1934
Creator: Biermann, Arnold E. & Pinkel, Benjamin
open access

The effect of baffles on the temperature distribution and heat-transfer coefficients of finned cylinders

Description: This report presents the results of an investigation to determine the effect of baffles on the temperature distribution and the heat-transfer coefficient of finned cylinders. The tests were conducted in a 30-inch wind tunnel on electrically heated cylinders with fins of 0.25 and 0.31 inch pitch. The results of these tests showed that the use of integral baffles gave a reduction of 31.9 percent in the rear wall temperatures and an increase of 54.2 percent in the heat transfer coefficient as comp… more
Date: September 26, 1934
Creator: Schey, Oscar W. & Rollin, Vern G.
open access

Effects of air-fuel spray and flame formation in a compression-ignition engine

Description: "High-speed motion pictures were taken at the rate of 2,500 frames per second of the fuel spray and flame formation in the combustion chamber of the NACA combustion apparatus. The compression ratio was 13.2 and the speed 1,500 revolutions per minute. An optical indicator was used to record the time-pressure relationship in the combustion chamber. The air-fuel ratio was varied from 10.4 to 365. The results showed that as the air-fuel ratio was increased definite stratification of the charge occu… more
Date: August 26, 1935
Creator: Rothrock, A. M. & Waldron, C. D.
open access

Comparative Flight and Full-Scale Wind-Tunnel Measurements of the Maximum Lift of an Airplane

Description: "Determinations of the power-off maximum lift of a Fairchild 22 airplane were made in the NACA full-scale wind tunnel and in flight. The results from the two types of test were in satisfactory agreement. It was found that, when the airplane was rotated positively in pitch through the angle of stall at rates of the order of 0.1 degree per second, the maximum lift coefficient was considerably higher than that obtained in the standard tests, in which the forces are measured with the angles of atta… more
Date: October 26, 1937
Creator: Silverstein, Abe; Katzoff, S. & Hootman, James A.
open access

The Transition Phase in the Take-Off of an Airplane

Description: Report presents the results of an investigation to determine the character and importance of the transition phase between the ground run and steady climb in the take-off of an airplane and the effects of various factors on this phase and on the air-borne part of the take-off as a whole. The information was obtained from a series of step-by-step integrations, which defined the motion of the airplane during the transition and which were based on data derived from actual take-off tests of a Vervil… more
Date: October 26, 1937
Creator: Wetmore, J. W.
open access

Determination of boundary-layer transition on three symmetrical airfoils in the NACA full-scale wind tunnel

Description: For the purpose of studying the transition from laminar to turbulent flow, boundary-layer measurements were made in the NACA full-scale wind tunnel on three symmetrical airfoils of NACA 0009, 0012, and 0018 sections. The effects of variations in lift coefficient, Reynolds number, and airfoil thickness on transition were investigated. Air speed in the boundary layer was measured by total-head tubes and by hot wires; a comparison of transition as indicated by the two techniques was obtained. The … more
Date: May 26, 1938
Creator: Silverstein, Abe & Becker, John V.
open access

Grinding machines

Description: This report provides the definition of grinding and discusses different processes, types, and operations of grinding.
Date: November 26, 1940
Creator: United States. Army. Air Corps.

Newsmap. Monday, October 26, 1942 : week of October 16 to October 23

Description: Front: Text describes action on various war fronts: Solomons -- New Guinea -- Aleutians -- Russia -- Shipping -- Mediterranean -- Yugoslavia -- Western Europe. Large world map is keyed to text and illustrates time zones around the world. Inset maps show Southwest Pacific -- Stalingrad. Includes photographs: Airport on Guadalcanal Island -- Somewhere in India [field artillery pieces and Gen. Stillwell's troops wearing German-type coal scuttle helmet] -- Supplies for Russia [Arctic convoy att… more
Date: October 26, 1942
Creator: [United States.] Army Orientation Course.
open access

Circumventing chloride ion trouble Columbia River water

Description: This report contains data acquired during sampling of the Columbia River water on March 26, 1945. Topics of discussion include; the elevation of chlorine levels from 4 ppm to 20 ppm, what steps should be taken to remediate the problem, and the various processes that were taken into consideration for the clean up of this chlorine. Separation processes considered include; ion exchange, distillation, precipitation, heat exchange, and recirculation through a cooling tower.
Date: March 26, 1943
Creator: Worthington, H.

Newsmap. Monday, April 26, 1943 : week of April 16 to April 23 : 189th week of the war, 71st week of U.S. participation

Description: Text describes action on various war fronts: Tunisia, Raid on Japan, Southwest Pacific, Italy, Air offensive, Russia, Aleutians. Large world map is keyed to text. Shows United Nations countries, Axis and Axis occupied areas, countries with Axis relations broken, and neutral countries. Inset maps show Italy, Sardinia, and northern Tunisia; Axis held areas in Tunisia; Nazi held areas around the Sea of Azov. Back: Fox Holes: Dig!..Or Die! Photographs and illustrations describing proper fox hol… more
Date: April 26, 1943
Creator: [United States.] Army Orientation Course.

Newsmap. Monday, July 26, 1943 : week of July 15 to July 22, 202nd week of the war, 84th week of U.S. participation

Description: Front: Text describes action on various war fronts: Sicily, Rome, Russia, New Guinea, Solomons, Paramushiru. Maps: Rome, Sicily, North Pacific Ocean. Inset maps: Italy and surrounding islands, Paramushiru. Photographs: Central railroad station and San Lorenzo yards in Rome; Escort Carrier B; Depth bomb bounces off side of submarine as another bomb drops into the water; Submarine sinks within 28 minutes; Junkers-52 Transport is reused as an office for an advanced U.S. Army Air Force Base. … more
Date: July 26, 1943
Creator: [United States.] Army Orientation Course.
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