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A method for calculating heat transfer in the laminar flow region of bodies

Description: Report presenting a practical method for determining the chordwise distribution of the rate of heat transfer from the surface of a wing or body of revolution to air. The method is limited to use to the determination of heat transfer fro the forward section of such bodies when the flow is laminar.
Date: December 1942
Creator: Allen, H. Julian & Look, Bonne C.
open access

A method for calculating heat transfer in the laminar flow region of bodies

Description: This report has been prepared to provide a practical method for determining the chordwise distribution of the rate of heat transfer from the surface of a wing or body of revolution to air. The method is limited in use to the determination of heat transfer from the forward section of such bodies when the flow is laminar. A comparison of the calculated average heat-transfer coefficient for the nose section of the wing of a Lockheed 12-A airplane with that experimentally determined shows a satisfa… more
Date: 1943
Creator: Allen, H. Julian & Look, Bonne C.
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The Effect of Compressibility on the Growth of the Laminar Boundary Layer on Low-Drag Wings and Bodies

Description: Report presenting a consideration of the development of the laminar boundary layer in a compressible fluid. Formulas are given for determining the boundary-layer thickness and the boundary-layer Reynolds number, which is a measure of the boundary-layer stability, for airfoils and bodies of revolution.
Date: July 1947
Creator: Allen, H. Julian & Nitzberg, Gerald E.
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The Effect of Compressibility on the Growth of the Laminar Boundary Layer on Low-Drag Wings and Bodies

Description: The development of the laminar boundary layer in a compressible fluid is considered. Formulas are given for determining the boundary-layer thickness and the ratio of the boundary-layer Reynolds number to the body Reynolds number for airfoils and bodies of revolution. It is shown that the effect of compressibility will profoundly alter the Reynolds number corresponding to the upper limit of the range of the low-drag coefficients.
Date: January 1943
Creator: Allen, H. Julian & Nitzberg, Gerald E.
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Characteristics of flow over inclined bodies of revolution

Description: From Summary: "Experimental force, moment, and center-of-pressure variations for a large number of bodies of revolution have been compared with the calculated characteristics based on the approximate theory developed in NACA-RM-A9I26. The bodies varied in fineness ratio from 4.5 to 21.1, from blunt unboattailed bodies to airship hulls, and the experimental results are given for widely varying Mach number ranges of angle of attack. It is shown that the lift and drag characteristics are fairly ac… more
Date: March 5, 1951
Creator: Allen, H. Julian & Perkins, Edward W.
open access

A study of effects of viscosity on flow over slender inclined bodies of revolution

Description: From Summary: "The observed flow field about slender inclined bodies of revolution is compared with the calculated characteristics based upon potential theory. The comparison is instructive in indicating the manner in which the effects of viscosity are manifest. Based on this and other studies, a method is developed to allow for viscous effects on the force and moment characteristics of bodies. The calculated force and moment characteristics of two bodies of high fineness ratio are shown to be … more
Date: 1951
Creator: Allen, H. Julian & Perkins, Edward W.
open access

Wall interference in a two-dimensional-flow wind tunnel with consideration of the effect of compressibility

Description: Report presenting tunnel-wall corrections for an airfoil of finite thickness and camber in a two-dimensional-flow wind tunnel. The theory takes account of the effects of the wake of the airfoil and of the compressibility of the fluid and is based on the assumption that the chord of the airfoil is small in comparison with the height of the tunnel. The theoretical results are compared with the small amount of low-speed experimental data available and agreement is seen to be satisfactory, even for… more
Date: December 1944
Creator: Allen, H. Julian & Vincenti, Walter G.
open access

Wall interference in a two-dimensional-flow wind tunnel, with consideration of the effect of compressibility

Description: From Summary: "Theoretical tunnel-wall corrections are derived for an airfoil of finite thickness and camber in a two-dimensional-flow wind tunnel. The theory takes account of the effects of the wake of the airfoil and of the compressibility of the fluid, and is based upon the assumption that the chord of the airfoil is small in comparison with the height of the tunnel. Consideration is given to the phenomenon of choking at high speeds and its relation to the tunnel-wall corrections. The theore… more
Date: 1944
Creator: Allen, H. Julian & Vincenti, Walter G.
open access

An Experimental Investigation of Several Low-Drag Wing-Nacelle Combinations with Internal Air Flow

Description: From Summary: "The results of an experimental investigation of several low-drag wing-nacelle combinations, incorporating internal air-flow systems, are presented. The external-drag increments due to these nacelles are between one-half and two-thirds of those of conventional nacelle forms. This improvement is accomplished with only minor effects on the lift and moment characteristics of the wing. The procedure employed to determine the external shape of such low-drag nacelles is considered in de… more
Date: March 1945
Creator: Allen, H. Julian; Frick, Charles W. & Erickson, Myles D.
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The interaction of boundary layer and compression shock and its effect upon airfoil pressure distributions

Description: Report presenting an investigation of the mechanism of interaction of compression shock with boundary layer. Shockless pressure distributions at supercritical Mach numbers were found to be accounted for by a marked thickening of the boundary layer for some distance ahead of a shock wave.
Date: April 10, 1947
Creator: Allen, H. Julian; Heaslet, Max A. & Nitzberg, Gerald E.
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Heat of Combustion of the Product Formed by the Reaction of Acetylene and Diborane (LFPL-CZ-3)

Description: The heat of combustion of the product formed by the reaction acetylene and diborane was found to be 20,100 +/- 100 Btu per pound for the reaction of liquid fuel to gaseous carbon dioxide, gaseous water, and solid boric oxide. The measurements were made in a Parr oxygen-bomb calorimeter, and chemical analyses both of the sample and of the combustion products indicated combustion in the bomb calorimeter to have been 97 percent complete. The estimated net heat of combustion for complete combustion… more
Date: October 24, 1957
Creator: Allen, Harrison, Jr. & Tannenbaum, Stanley
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Chemical and Physical Properties of Modified Hi-Cal-2

Description: Memorandum presenting some physical and chemical properties of a sample of modified Hi-Cal-2. Some of the results obtained include chemical analysis, heat of combustion, density, freezing point, self-ignition temperature, flash point, oxygen stability, water stability test, infrared spectrum, and vapor pressure and decomposition are provided.
Date: December 1955
Creator: Allen, Harrison, Jr.; McDonald, Glen E. & Pusanski, Barbara J.
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Visualization study of secondary flows in turbine rotor tip regions

Description: Report presenting a visualization study using smoke to see the secondary-flow phenomena in the rotor-blade tip region of a low-speed turbine. Measurements of the factors affecting the flow patterns were recorded from visual observations. Results regarding a general description of the smoke patterns, shroud boundary-layer considerations, transition rotor tip speed, and high-speed-turbine operating conditions are provided.
Date: September 1955
Creator: Allen, Hubert W. & Kofskey, Milton G.
open access

Force and pressure recovery characteristics at supersonic speeds of a conical spike inlet with a bypass discharging from the top or bottom of the diffuser in an axial direction

Description: Force and pressure-recovery characteristics of a nacelle-type conical-spike inlet with a fixed-area bypass located in the top or bottom of the diffuser are presented for flight Mach numbers of 1.6, 1.8, and 2.0 for angles of attack from 0 degrees to 9 degrees. Top or bottom location of the bypass did not have significant effects on diffuser pressure-recovery, bypass mass-flow ratio, or drag coefficient over the range of angles of attack, flight Mach numbers, and stable engine mass-flow ratios i… more
Date: March 23, 1953
Creator: Allen, J. L. & Beke, Andrew
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Force and pressure recovery characteristics at supersonic speeds of a conical spike inlet with bypasses discharging in an axial direction

Description: Report presenting an investigation of an axially symmetric nacelle-type conical spike inlet with two bypasses located in the horizontal plane and on opposite sides of the nacelle in the 8- by 6-foot supersonic tunnel at several Mach numbers and angles of attack. Results regarding the performance with open bypasses and with closed bypasses are provided.
Date: January 30, 1953
Creator: Allen, J. L. & Beke, Andrew
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Performance comparison at supersonic speeds of inlets spilling excess flow by means of bow shock, conical shock, or bypass

Description: Report presenting a comparison of fixed-geometry, translating-spike, and bypass-inlets on the basis of turbojet- and ramjet-engine performance. Results regarding a comparison of the experimental data and its application to ramjet and turbojet engines are provided.
Date: October 23, 1953
Creator: Allen, J. L. & Beke, Andrew
open access

Performance Characteristics at Mach Numbers to 2.0 of Various Types of Side Inlets Mounted on Fuselage of Proposed Supersonic Airplane 2: Inlets Utilizing Half of a Conical Spike

Description: Report presenting an investigation to determine the performance of twin-scoop side inlets mounted on the fuselage of a proposed supersonic aircraft. The inlets had half of a conical spike as the compression surface and a ram-type boundary-layer-removal system. Results regarding the first inlet and redesigned inlet are provided.
Date: September 4, 1952
Creator: Allen, J. L. & Simon, P. C.
open access

Performance of a blunt-lip side inlet with ramp bleed, bypass, and a long constant-area duct ahead of the engine : Mach number 0.66 and 1.5 to 2.1

Description: Unsteady shock-induced separation of the ramp boundary layer was reduced and stabilized more effectively by external perforations than by external or internal slots. At Mach 2.0 peak total-pressure recovery was increased from 0.802 to 0.89 and stable mass-flow range was increased 185 percent over that for the solid ramp. Peak pressure recovery occurred just before instability. The 7 and one-third-diameter duct ahead of the engine reduced large total-pressure distortions but was not as successfu… more
Date: December 28, 1956
Creator: Allen, John L.
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Performance of a Blunt-lip Side Inlet With Ramp Bleed, Bypass, and a Long Constant-area Duct Ahead of the Engine- Mach Numbers 0.66 and 1.5 to 2.1

Description: Report presenting the performance of a side inlet with a fixed 12 degree two-dimensional compression surface for a range of Mach numbers, angles of attack, and yaw. The effects of several methods of compression-surface boundary-layer removal were investigated as well as a solid ramp.
Date: December 28, 1956
Creator: Allen, John L.
open access

Performance of an Inlet Having a Variable-angle Two-dimensional Compression Surface and a Fixed-geometry Subsonic Diffuser for Application to Reduced Engine Rotative Speeds- Mach Numbers 0.66, 1.5, 1.7, and 2.0

Description: Report presenting the performance of a two-dimensional side inlet with a technique of varying compression-surface angle while retaining a fixed-geometry diffuser at several Mach numbers and zero angle of attack. A 12 degree compression ramp was faired into the diffuser contour in this conventional manner. Results regarding the inlet flow field, application to reduced engine speeds, and a inlet performance with a sudden expansion in the diffuser are provided.
Date: January 30, 1958
Creator: Allen, John L.
open access

Preliminary investigation of effect on performance of dividing conical-spike nose inlets into halves at Mach numbers 1.5 to 2.0

Description: Inserting a splitter plate in the subsonic diffuser caused a pressure-recovery loss of about 1 percent for an inlet with a long nearly constant-area throat section. The loss was due to the increased surface area. Another inlet, which had a comparatively rapid area increase immediately after the throat, experienced pressure-recovery losses of 5 and 6 percent at Mach numbers of 1.8 and 2.0, respectively, and about 1 percent at Mach 1.5.
Date: December 19, 1955
Creator: Allen, John L.
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