The Flow of a Compressible Fluid Past a Circular Arc Profile (open access)

The Flow of a Compressible Fluid Past a Circular Arc Profile

"The Ackeret iteration process is utilized to obtain higher approximations than that of Prandtl and Glauert for the flow of a compressible fluid past a circular arc profile. The procedure is to expand the velocity potential in a power series of the camber coefficient. The first two terms of the development correspond to the Prandtl-Glauert approximation and yield the well-known correction to the circulation about the profile" (p. 385).
Date: July 15, 1944
Creator: Kaplan, Carl
System: The UNT Digital Library
Method of Matching Performance of Compressor Systems with that of Aircraft Power Sections (open access)

Method of Matching Performance of Compressor Systems with that of Aircraft Power Sections

"A method is developed of easily determining the performance of a compressor system relative to that of the power section for a given altitude. Because compressors, reciprocating engines, and turbines are essentially flow devices, the performance of each of these power-plant components is presented in terms of similar dimensionless ratios. The pressure and temperature changes resulting from restrictions of the charge-air flow and from heat transfer in the ducts connecting the components of the power plant are also expressed by the same dimensionless ratios and the losses are included in the performance of the compressor" (p. 119).
Date: November 15, 1945
Creator: Bullock, Robert O.; Keetch, Robert C. & Moses, Jason J.
System: The UNT Digital Library
Effects of Small Angles of Sweep and Moderate Amounts of Dihedral on Stalling and Lateral Characteristics of a Wing-Fuselage Combination Equipped With Partial- and Full-Span Double Slotted Flaps (open access)

Effects of Small Angles of Sweep and Moderate Amounts of Dihedral on Stalling and Lateral Characteristics of a Wing-Fuselage Combination Equipped With Partial- and Full-Span Double Slotted Flaps

"Tests of a wing-fuselage combinations incorporating NACA 65-series airfoil sections were conducted in the NACA 19-foot pressure tunnel. The investigation included the tests with flaps neutral and with partial- and full-span double slotted flaps deflected to determine the effects of (1) variations of wing sweep between -4 degrees and 8 degrees on stalling and lateral stability and control characteristics and (2) variations of dihedral between 0 degree and 6.75 degrees on lateral stability characteristics" (p. 467).
Date: April 15, 1944
Creator: Teplitz, Jerome
System: The UNT Digital Library
Application of Theodorsen's theory to propeller design (open access)

Application of Theodorsen's theory to propeller design

A theoretical analysis is presented for obtaining, by use of Theodorsen's propeller theory, the load distribution along a propeller radius to give the optimum propeller efficiency for any design condition. The efficiencies realized by designing for the optimum load distribution are given in graphs, and the optimum efficiency for any design condition may be read directly from the graph without any laborious calculations. Examples are included to illustrate the method of obtaining the optimum load distributions for both single-rotating and dual-rotating propellers.
Date: March 15, 1948
Creator: Crigler, John L.
System: The UNT Digital Library
Analysis of variation of piston temperature with piston dimensions and undercrown cooling (open access)

Analysis of variation of piston temperature with piston dimensions and undercrown cooling

From Summary: "A theoretical analysis is presented that permits estimation of the changes in piston-temperature distribution induced by variations in the crown thickness, the ring-groove-pad thickness, and the undercrown surface heat-transfer coefficient. The analysis consists of the calculation of operating temperatures at various points in the piston body on the basis of the experimentally determined surface heat-transfer coefficients and boundary-region temperatures, as well as arbitrarily selected surface coefficients."
Date: January 15, 1948
Creator: Sanders, J. C. & Schramm, W. B.
System: The UNT Digital Library
Consideration of Dynamic Loads on the Vertical Tail by the Theory of Flat Yawing Maneuvers (open access)

Consideration of Dynamic Loads on the Vertical Tail by the Theory of Flat Yawing Maneuvers

"Dynamic yawing effects on vertical-tail loads are considered by a theory of flat yawing maneuvers. A comparison is shown between computed loads and the loads measured in flight on a fighter airplane. The dynamic effects were investigated on a large flying boat for both an abrupt rudder deflection and sinusoidal rudder deflection" (p. 91).
Date: March 15, 1946
Creator: Boshar, John & Davis, Philip
System: The UNT Digital Library
An Analysis of the Stability of an Airplane With Free Controls (open access)

An Analysis of the Stability of an Airplane With Free Controls

Report presents the results of an investigation made of the essentials to the stability of an airplane with free control surfaces.
Date: August 15, 1940
Creator: Jones, Robert T. & Cohen, Doris
System: The UNT Digital Library
Theoretical lift and damping in roll at supersonic speeds of thin sweptback tapered wings with streamwise tips, subsonic leading edges, and supersonic trailing edges (open access)

Theoretical lift and damping in roll at supersonic speeds of thin sweptback tapered wings with streamwise tips, subsonic leading edges, and supersonic trailing edges

"On the basis of linearized supersonic-flow theory, generalized equations were derived and calculations made for the lift and damping in roll of a limited series of thin sweptback tapered wings. Results are applicable to wings with streamwise tips and for a range of supersonic speeds for which the wing is wholly contained between the Mach cones springing from the wing apex and from the trailing edge of the root section. A further limitation is that the tip Mach lines may not intersect on the wing" (p. 395).
Date: February 15, 1949
Creator: Malvestuto, Frank S., Jr.; Margolis, Kenneth & Ribner, Herbert S.
System: The UNT Digital Library