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Wind-tunnel tests of single- and dual-rotating pusher propellers having from three to eight blades

Description: Report presenting tests of 10-foot-diameter, single- and dual-rotating pusher propellers with three to eight blades that were conducted in the 20-foot propeller research tunnel as a continuation of previous investigations of tractor propellers. The propellers were mounted at the rear end of a streamline body in spinners that covered the hubs and part of the shanks. The effects as compared to previous testing differed only in degree of effect size.
Date: February 1942
Creator: Gray, W. H.
Partner: UNT Libraries Government Documents Department

Full-scale wind-tunnel tests of a propeller with the diameter changed by cutting off the blade tips

Description: Tests were conducted in order to determine how the characteristics of a propeller are affected by cutting off the tips. The diameter of a standard 10-foot metal propeller was changed successively to 9 feet 6 inches, 9 feet 0 inches, 8 feet 6 inches, and 8 feet 0 inches. Each propeller thus formed was tested at four pitch settings using an open cockpit fuselage and a D-12 engine. A small loss in propulsive efficiency is indicated. Examples are given showing the application of the results to practical problems.
Date: December 10, 1929
Creator: Wood, Donald H.
Partner: UNT Libraries Government Documents Department

Full-scale tests of metal propellers at high tip speeds

Description: This report describes tests of 10 full-scale metal propellers of several thickness ratios at various tip speeds up to 1,350 feet per second. The results indicate no loss of efficiency up to tip speeds of approximately 1,000 feet per second. Above this tip speed the loss is at a rate of about 10 per cent per 100 feet per second increase relative to the efficiency at the lower speeds for propellers of pitch diameter ratios 0.3 to 0.4. Propellers having sections of small thickness ratio can be run at slightly higher speeds than thick ones before beginning to lose efficiency.
Date: November 5, 1930
Creator: Wood, Donald H.
Partner: UNT Libraries Government Documents Department

Turbine performance characteristics of a python turbine-propeller engine investigated in altitude wind tunnel

Description: Report presenting the performance of the turbine component of a Python turbine-propeller engine with four tail-pipe configurations determined over a range of altitudes, engine speeds, and fuel flows. Results regarding the corrected turbine speed, corrected turbine enthalpy drop, pressure ratio, and efficiency were established on a turbine-characteristic plot.
Date: May 1, 1951
Creator: Farley, John M. & Prince, William R.
Partner: UNT Libraries Government Documents Department

The effect of blade-section thickness ratio on the aerodynamic characteristics of related full-scale propellers at Mach numbers up to 0.65

Description: The results of an investigation of two 10-foot-diameter, two-blade NACA propellers are presented for a range of blade angles from 20 degrees to 55 degrees at airspeeds up to 500 miles per hour. These results are compared with those from previous investigations of five related NACA propellers in order to evaluate the effects of blade-section thickness ratios on propeller aerodynamic characteristics.
Date: April 25, 1949
Creator: Maynard, Julian D. & Steinberg, Seymour
Partner: UNT Libraries Government Documents Department

Investigation of the effect of a tip modification and thermal de-icing air flow on propeller performance

Description: Report presenting aerodynamic testing of 12.208-foot-diameter two-blade hollow steel propellers before and after alteration for thermal de-icing in the 16-foot high-speed tunnel to determine the effect of the alterations on propeller efficiency. The propeller had Clark Y blade sections tested on a 2000-horsepower dynamometer at a range of blade angles and airspeeds. Results regarding accuracy, the effect of the alteration, effect of internal air flow, effect of compressibility, and coefficient of mass flow of de-icing air are provided.
Date: July 1946
Creator: Corson, Blake W., Jr. & Maynard, Julian D.
Partner: UNT Libraries Government Documents Department

The Langley 2,000-horsepower propeller dynamometer and tests at high speed of an NACA 10-(3)(08)-03 two-blade propeller

Description: This paper contains a detailed description of a 2,000-horsepower propeller dynamometer used to make wind-tunnel tests of a two-blade NACA 10-(3)(08)-03 propeller for a range of blade angles from 20 degrees to 55 degrees at airspeeds up to 500 miles per hour. The results of these tests and comparisons with results obtained from a theoretical analysis and from previous tests made in other wind tunnels are presented.
Date: December 1952
Creator: Corson, Blake W., Jr. & Maynard, Julian D.
Partner: UNT Libraries Government Documents Department

The NACA 2000-horsepower propeller dynamometer and tests at high speed of an NACA 10-(3)(08)-03 two-blade propeller

Description: This paper contains a detailed description of a 2,000-horsepower propeller dynamometer used to make wind-tunnel tests of a two-blade NACA 10-(3)(08)-03 propeller for a range of blade angles from 20 degrees to 55 degrees at airspeeds up to 500 miles per hour. The results of these tests and comparisons with results obtained from a theoretical analysis and from previous tests made in other wind tunnels are presented.
Date: July 20, 1948
Creator: Corson, Blake W., Jr. & Maynard, Julian D.
Partner: UNT Libraries Government Documents Department

Wind-tunnel vibration tests of dual-rotating propellers

Description: Report presenting vibration tests of six- and eight-blade tractor and seven- and eight-blade pusher dual-rotating propellers conducted in the 16-foot high-speed tunnel to determine the severity of vibrations excited by blade passages. Measurements of vibratory stresses were made for engine-speed ranges at low, intermediate, and high engine powers. Few vibrations caused by blade passages were detected, and those vibrations were not serious.
Date: September 1943
Creator: Miller, Mason F.
Partner: UNT Libraries Government Documents Department

Considerations of wake-excited vibratory stress in a pusher propeller

Description: Report presenting an equation based on simple blade-element theory and the assumption of a fixed wake pattern is derived and fitted to available data to show the first-order relation between the parameters of propeller operation and intensity of wake-excited periodic force acting on the blades of a pusher propeller. The derived equation indicates that the effect of power coefficient on the intensity of the wake-excited periodic force is small. Limited data also indicates that the wake-excited vibratory stress in a propeller increases with the drag of the body producing the wake.
Date: February 1944
Creator: Corson, Blake W., Jr.
Partner: UNT Libraries Government Documents Department

Wind-tunnel tests of single- and dual-rotating tractor propellers of large blade width

Description: Report presenting tests of 10-foot diameter, single- and dual-rotating tractor propellers with two to eight blades conducted in the 20-foot propeller-research tunnel. The blades were 50 percent wider than those used in previous investigations. Results regarding the effect of dual rotation and effect of solidity are provided.
Date: September 1942
Creator: Biermann, David; Gray, W. H. & Maynard, Julian D.
Partner: UNT Libraries Government Documents Department

Preliminary investigation of the characteristics of a two dimensional wing and propeller with the propeller plane of rotation in the wing-chord plane

Description: Report detailing an investigation of the aerodynamic characteristics of a wing-propeller combination with the propeller rotating in the wing-chord plane of a two-dimensional wing. Total static lift was measured with and without the wing for a 3-foot-diameter propeller, while the effects of a ground plane on the static lift of the wing-propeller combination were measured with a 2-foot-diameter propeller. Results regarding static testing, forward speed tests, and propeller loads are provided.
Date: August 1, 1957
Creator: Hickey, David H.
Partner: UNT Libraries Government Documents Department

Aerodynamic investigation of a four-blade propeller operating through an angle-of-attack range from 0 to 180 degrees

Description: Report presenting an investigation of the aerodynamic characteristics of a four-blade rigid model propeller in the full-scale tunnel for a range of angles of attack, blade angles, and advance ratio. It included a preliminary explanation of vertical descent and a comparison with theory. Results regarding the static thrust and forward flight are provided.
Date: June 1954
Creator: McLemore, H. Clyde & Cannon, Michael D.
Partner: UNT Libraries Government Documents Department

Comparison of full-scale propellers having R.A.F.-6 and Clark Y airfoil sections

Description: In this report the efficiencies of two series of propellers having two types of blade sections are compared. Six full-scale propellers were used, three having R. A. F.-6 and three Clark Y airfoil sections with thickness/chord ratios of 0.06, 0.08, and 0.10. The propellers were tested at five pitch setting, which covered the range ordinarily used in practice. The propellers having the Clark Y sections gave the highest peak efficiency at the low pitch settings. At the high pitch settings, the propellers with R. A. F.-6 sections gave about the same maximum efficiency as the Clark Y propellers and were more efficient for the conditions of climb and take-off.
Date: October 8, 1930
Creator: Freeman, Hugh B.
Partner: UNT Libraries Government Documents Department

Static tests of a shrouded and an unshrouded propeller

Description: Report presenting outdoor static testing made on two high-solidity propellers of different design, one shrouded and the other unshrouded. Three shrouds were tested to determine the effects of shroud length and exit area. Results regarding the action of shroud, results and comparison of propellers, and comparison with theory are provided.
Date: February 9, 1948
Creator: Platt, Robert J., Jr.
Partner: UNT Libraries Government Documents Department

The Characteristics of Two Model Six-Blade Counterrotating Pusher Propellers of Conventional and Improved Aerodynamic Design

Description: Two airfoil plans were used for propeller blades. One is modified Clark Y section designed for structural reliability and the second an NACA 16 airfoil section designed to produce minimum aerodynamic losses. At low air speeds, the propeller designed for aerodynamic effects showed a gain of from 1.5 to 4.0 percent in propulsive efficiency over the conventional type depending on the pitch. Because of the numerous variables involved, the effect of each one on the aerodynamic characteristics of the propellers could not be isolated.
Date: June 1942
Creator: McHugh, James G. & Pepper, Edward
Partner: UNT Libraries Government Documents Department

Tests of 16 related airfoils at high speed

Description: From Summary: "In order to provide information that might lead to the development of better propeller section, 13 related symmetrical airfoils were tested in the NACA high-speed wind tunnel for a study of the effect of thickness form on the aerodynamic characteristics. The thickness-form variables studies were the value of the maximum thickness, the position along the chord at which the maximum thickness occurs, and the value of the leading-edge radius. The tests were conducted through the low angle-of-attack range for speeds extending from 35 percent of that of sound to slightly in excess of the speed at which a compressibility burble, or breakdown of flow, occurs. The corresponding Reynolds number range is 350,000 to 750,000."
Date: April 28, 1934
Creator: Stack, John & von Doenhoff, Albert E.
Partner: UNT Libraries Government Documents Department

Experimental and calculated static characteristics of a two-blade NACA 10-(3)(062)-045 propeller

Description: Report presenting an investigation to determine the static characteristics of a two-blade NACA 10-(3)(062)-045 propeller. Experimental data were obtained for a blade-angle range from -5 degrees to 40 degrees measured at the 0.75 radial station and for tip Mach numbers up to 1.0.
Date: March 12, 1954
Creator: Swihart, John M.
Partner: UNT Libraries Government Documents Department

The influence of blade-width distribution on propeller characteristics

Description: Report presenting combined force and wake survey tests on three-blade model propellers in order to determine the effects of blade-width distribution on constant-speed efficiency characteristics. The most important result is the demonstration that blade-width distribution has a marked influence on the constant-speed efficiency characteristics of propellers.
Date: March 1949
Creator: Reid, Elliott G.
Partner: UNT Libraries Government Documents Department

The effects of hub drag, solidity, dual rotation, and number of blades upon the efficiency of high-pitch propellers

Description: Report presenting an investigation of the effects of hub drag, solidity, dual rotation, and number of blades on the efficiency of high-pitch propellers. Testing occurred with two, three, four, and six-blade single propellers and four and six-blade dual-rotating propellers equipped with spinners and tested at a range of blade angles from 35 to 65 degrees. Results regarding a comparison of the large and small spinners, effects of spinners, comparison of constant-speed propellers, characteristics of constant-speed propellers, effect of solidity and dual rotation, effect of number of blades, and some peculiarities of four-blade propellers are provided.
Date: October 1941
Creator: Reid, Elliott G.
Partner: UNT Libraries Government Documents Department

Wake studies of eight model propellers

Description: Report presenting an investigation of the influences of shank form and pitch distribution on the characteristics of constant-speed propellers as determine from the wakes of eight model propellers. The experiments show that an improvement in efficiency occurs from the substitution of faired shanks for round ones, which is caused by disproportionate local augmentations of thrust and torque. Results regarding a comparison with force tests, method of comparing performance characteristics, effects of shank form, effects of pitch distribution, independence of blade elements, and section lift characteristics are provided.
Date: July 1946
Creator: Reid, Elliott G.
Partner: UNT Libraries Government Documents Department

Measurements of free-space oscillating pressures near a propeller at flight Mach numbers to 0.72

Description: Report presenting a series of measurements at three stations of the oscillating pressures near the propeller at flight Mach numbers up to 0.72. The measurements were made at a single radial station and three axial positions. Results regarding effect of engine speed at constant flight Mach number and power and effect of flight Mach number at constant engine speed and power are provided.
Date: May 1955
Creator: Vogeley, Arthur W. & Kurbjun, Max C.
Partner: UNT Libraries Government Documents Department

Measurements of free-space oscillating pressures near propellers at flight Mach numbers to 0.72

Description: "In the course of a short flight program initiated to check the theory of Garrick and Watkins (NACA rep. 1198), a series of measurements at three stations were made of the oscillating pressures near a tapered-blade plan-form propeller and rectangular-blade plan form propeller at flight Mach numbers up to 0.72. In contradiction to the results for the propeller studied in NACA rep. 1198, the oscillating pressures in the plane ahead of the propeller were found to be higher than those immediately behind the propeller. Factors such as variation in torque and thrust distribution, since the blades of the present investigation were operating above their design forward speed, may account for this contradiction" (p. 999).
Date: July 1, 1958
Creator: Kurbjun, Max C. & Vogeley, Arthur W.
Partner: UNT Libraries Government Documents Department