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Glatt, L.

Publications and source records attributed to Glatt, L..

Generalized Advanced Propeller Analysis System (GAPAS). Volume 2: Computer program user manual

The Generalized Advanced Propeller Analysis System (GAPAS) computer code is described. GAPAS was developed to analyze advanced technology multi-bladed propellers which operate on aircraft with speeds up to Mach 0.8 and altitudes up to 40,000 feet. GAPAS includes technology for analyzing aerodynamic, structural, and acoustic performance of propellers. The computer code was developed for the CDC 7600 computer and is currently available for industrial use on the NASA Langley computer. A description of all the analytical models incorporated in GAPAS is included. Sample calculations are also described as well as users requirements for modifying the analysis system. Computer system core requirements and running times are also discussed.

Glatt, L.

The development of a generalized advanced propeller analysis system

A Generalized Advanced Propeller Analysis System (GAPAS) is being developed to provide both an optimized design and a performance evaluation capability. The technology areas incorporated in GAPAS include propeller aerodynamic performance, airfoil loading, acoustics, structural analysis and aeroelasticity. The propeller analyses include the most advanced, fully-developed technologies in a modular but unified system. The program will treat multi-bladed propellers having straight or swept blades operating on aircraft at speeds to Mach 0.8 and altitudes to 40,000 feet. The purpose of this paper is twofold. First, it will introduce the GAPAS program to the general industry; and second, since the GAPAS program will be made available for general applications, it is also intended to be a status report on the development stage of the program.

Glatt, L.

Aircraft HO sub x and NO sub x emission effects on stratospheric ozone and temperature

A simplified two-dimensional steady-state photochemical model of the atmosphere was developed. The model was used to study the effect on the thermal and chemical structure of the atmosphere of two types of pollution cases: (1) injection of NOx and HOx from a hypothetical fleet of supersonic and subsonic aircraft and (2) injection of HOx from a hypothetical fleet of liquid-fueled hydrogen aircraft. The results are discussed with regard to stratospheric perturbations in ozone, water vapor and temperature.

Glatt, L.