Serial/Series Title

Equilibrium Operating Performance of Axial-Flow Turbojet Engines by Means of Idealized Analysis (open access)

Equilibrium Operating Performance of Axial-Flow Turbojet Engines by Means of Idealized Analysis

"A method of predicting equilibrium operating performance of turbojet engines has been developed, with the assumption of simple model processes for the components. Results of the analysis are plotted in terms of dimensionless parameters comprising critical engine dimensions and over-all operating variables. This investigation was made of an engine in which the ratio of axial inlet-air velocity to compressor-tip velocity is constant, which approximates turbojet engines with axial-flow compressors" (p. 673).
Date: February 25, 1949
Creator: Sanders, John C. & Chapin, Edward C.
System: The UNT Digital Library
Intercooler cooling-air weight flow and pressure drop for minimum drag loss (open access)

Intercooler cooling-air weight flow and pressure drop for minimum drag loss

An analysis has been made of the drag losses in airplane flight of cross-flow plate and tubular intercoolers to determine the cooling-air weight flow and pressure drop that give a minimum drag loss for any given cooling effectiveness and, thus, a maximum power-plant net gain due to charge-air cooling. The drag losses considered in this analysis are those due to (1) the extra drag imposed on the airplane by the weight of the intercooler, its duct, and its supports and (2) the drag sustained by the cooling air in flowing through the intercooler and its duct. The investigation covers a range of conditions of altitude, airspeed, lift-drag ratio, supercharger-pressure ratio, and supercharger adiabatic efficiency. The optimum values of cooling air pressure drop and weight flow ratio are tabulated. Curves are presented to illustrate the results of the analysis.
Date: February 25, 1944
Creator: Reuter, J. George & Valerino, Michael F.
System: The UNT Digital Library
The effect of blade-section thickness ratio on the aerodynamic characteristics of related full-scale propellers at Mach numbers up to 0.65 (open access)

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

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
System: The UNT Digital Library
General algebraic method applied to control analysis of complex engine types (open access)

General algebraic method applied to control analysis of complex engine types

"A general algebraic method of attack on the problem of controlling gas-turbine engines having any number of independent variables was utilized employing operational functions to describe the assumed linear characteristics for the engine, the control, and the other units in the system. Matrices were used to describe the various units of the system, to form a combined system showing all effects, and to form a single condensed matrix showing the principal effects. This method directly led to the conditions on the control system for noninteraction so that any setting disturbance would affect only its corresponding controlled variable" (p. 581).
Date: April 25, 1949
Creator: Boksenbom, Aaron S. & Hood, Richard
System: The UNT Digital Library
Flight measurements of the lateral control characteristics of narrow-chord ailerons on the trailing edge of a full-span slotted flap (open access)

Flight measurements of the lateral control characteristics of narrow-chord ailerons on the trailing edge of a full-span slotted flap

From Summary: "Results are presented of light tests made to determine the effect of flap deflection on the lateral control characteristics of a modified Brewster F2A-2 airplane equipped with partial-span narrow-chord ailerons on the trailing edge of a full-span NACA slotted flap. The investigation included determination of the rolling and yawing characteristics of the airplane in abrupt aileron rolls with the slotted flap at various settings ranging from 0 degree to about 40 degrees. The results showed that the effectiveness of the ailerons was greatly reduced at flap deflections greater than about 20 degrees. For flap deflections up to about 20 degrees, the aileron effectiveness was about the same as with flaps retracted, but the adverse yawing velocity developed in the abrupt aileron rolls was somewhat increased."
Date: October 25, 1946
Creator: Sawyer, Richard H.
System: The UNT Digital Library