Thrust Nozzles for Supersonic Transport Aircraft

Supersonic transports will require jet-engine thrust nozzles that are highly efficient from take-off to supersonic cruise in order to minimize the direct operating costs. Variable-area ejectors, plug nozzles, and modifications of these basic types have been tested extensively during the past several years. Performance trends for these nozzles are presented with the emphasis on external flow effects. A new ejector which utilizes aerodynamically actuated doors to admit external air into the ejector shroud is discussed.

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A Propulsion Perspective of the Next Generation Supersonic Transport

Volume 2: Aircraft Engine; Marine; Microturbines and Small Turbomachinery ◽

10.1115/91-gt-385 ◽

1991 ◽

Cited By ~ 1

Author(s):

P. D. Feig ◽

S. C. Gilkey

Keyword(s):

Second Generation ◽

Environmental Issues ◽

Air Travel ◽

International Travel ◽

Engine Emissions ◽

Ongoing Research ◽

Transport Aircraft ◽

Supersonic Transport ◽

The Past ◽

Insight Into

There is a growing, worldwide interest in a second generation supersonic transport aircraft. Air travel has tripled in the past 20 years to approximately 1000 billion revenue-passenger-miles per year. By the year 2010, air travel is anticipated to be 2 1/2 times that value, with long-range international travel the fastest growing segment. In order to become a reality, the second generation supersonic transport must be both environmentally acceptable and economically competitive with future subsonic aircraft. Current research is now focused on addressing the major environmental issues of airport noise, engine emissions, and sonic boom. GE is studying a variety of engine and exhaust nozzle concepts and validating the emissions and acoustics technologies needed for this aircraft. In 1990, GE and P&W decided to work together to explore the feasibility of developing a second generation SST propulsion system. This paper provides an insight into our ongoing research and highlights the propulsion system’s influence on the viability of the second generation SST.

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Centre-Body Nozzles for Supersonic Transport Aircraft

Journal of the Royal Aeronautical Society ◽

10.1017/s000192400005644x ◽

1967 ◽

Vol 71 (673) ◽

pp. 14-22

Author(s):

M. V. Herbert

Keyword(s):

Gas Turbine ◽

Test Data ◽

High Efficiency ◽

Pressure Ratio ◽

External Flow ◽

Body Form ◽

Transport Aircraft ◽

Supersonic Transport ◽

Wide Range ◽

Twin Models

SummaryIn a supersonic transport aircraft, the propelling nozzle is required to operate at high efficiency over a wide range of conditions — typically a five to ten-fold variation of exhaust pressure ratio. This paper offers some discussion around the problems of geometry which such requirements entail, and explains the reasons for which a nozzle of centre-body form with parallel outer shroud appears an attractive solution. In support of the claims for this arrangement of nozzle, test data are presented from both single and twin models under representative conditions of external flow. (The tests were made at the National Gas Turbine Establishment between 1960 and 1965.)

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An estimation method for the fuel burn and other performance characteristics of civil transport aircraft during cruise: part 2, determining the aircraft’s characteristic parameters

The Aeronautical Journal ◽

10.1017/aer.2020.124 ◽

2020 ◽

Vol 125 (1284) ◽

pp. 296-340

Author(s):

D.I.A. Poll ◽

U. Schumann

Keyword(s):

Estimation Method ◽

Accurate Method ◽

Characteristic Parameters ◽

Transport Aircraft ◽

The Public ◽

Engine Thrust ◽

Fuel Burn ◽

Burn Rate ◽

Drag Ratio ◽

Independent Parameters

ABSTRACTA simple yet physically comprehensive and accurate method for the estimation of the cruise fuel burn rate of turbofan powered transport aircraft operating in a general atmosphere was developed in part 1. The method is built on previously published work showing that suitable normalisation reduces the governing relations to a set of near-universal curves. However, to apply the method to a specific aircraft, values must be assigned to six independent parameters and the more accurate these values are the more accurate the estimates will be. Unfortunately, some of these parameters rarely appear in the public domain. Consequently, a scheme for their estimation is developed herein using basic aerodynamic theory and data correlations. In addition, the basic method is extended to provide estimates for cruise lift-to-drag ratio, engine thrust and engine overall efficiency. This step requires the introduction of two more independent parameters, increasing the total number from six to eight. An error estimate and sensitivity analysis indicates that, in the aircraft’s normal operating range and using the present results, estimates of fuel burn rate are expected to be in error by no more than 5% in the majority of cases. Initial estimates of the characteristic parameters have been generated for 53 aircraft types and engine combinations and a table is provided.

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A Review of Desiccant Cooling Systems

Journal of Energy Resources Technology ◽

10.1115/1.2905965 ◽

1993 ◽

Vol 115 (1) ◽

pp. 1-8 ◽

Cited By ~ 117

Author(s):

D. G. Waugaman ◽

A. Kini ◽

C. F. Kettleborough

Keyword(s):

Operating Costs ◽

Coefficient Of Performance ◽

Low Grade ◽

Cooling Systems ◽

The Past ◽

Cooling Coils ◽

Conventional Cooling ◽

Commercial Applications ◽

Conventional Systems ◽

Made In

This paper describes recent published design advances that have been made in desiccant cooling systems. In desiccant cooling cycles, the desiccant reduces the humidity of the air by removing moisture from the air. Then the temperature is reduced by other components such as heat exchangers, evaporative coolers, or conventional cooling coils. The main advantage that desiccant cooling systems offer is the capability of using low-grade thermal energy. Desiccant cooling systems for residential and commercial applications are now being used to reduce energy-operating costs. However, the initial costs are comparatively high. The focus of research for the past decade has been to develop desiccant systems with a high coefficient of performance. Recent studies have emphasized computer modeling and hybrid systems that combine desiccant dehumidifiers with conventional systems.

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