scholarly journals American Airlines Experience With Turbojet/Turbofan Engines

1962 ◽  
Author(s):  
K. F. Whatley
Keyword(s):  
First Generation ◽  
Engine Operation ◽  
Turbofan Engines ◽  
Growing Pains ◽  
Commercial Operation ◽  
Improvement Programs ◽  
Thrust Reverser ◽  
Considerable Period ◽  
Engine Reliability ◽  
American Airlines

The turbojet engine JT3C-6 and JT3C-7 entered commercial service on American Airlines Boeing 707/720 Aircraft after a considerable period of experience resulting from military J57 operation. Although the commercial operation uncovered problem areas, the causes were defined and the engine reliability and serviceability responded to various improvement programs. The time between overhauls (TBO) increased from 800 to 2100 hr at a rate unparalled in commercial engine operation. The turbofan is now going through a period of commercial “growing pains.” Problems have resulted from higher thrust, use of new materials, higher temperatures within and outside the engine, complexities of a fan air-thrust reverser, and so on. The airframe and engine manufacturers have defined these problems and together with the commercial operators are engaged in programs to insure performance and reliability compatible with the tremendous success of the first generation JT3C-6 and JT3C-7 turbojets.

scholarly journals Two-Stage Selection in Slash Pine Produces Good Gains in Fusiform Rust Resistance

1996 ◽  
Vol 20 (3) ◽  
pp. 143-147 ◽  
Author(s):  
Earl R. Sluder
Keyword(s):  
Combining Ability ◽  
Rust Resistance ◽  
First Generation ◽  
Diallel Cross ◽  
Slash Pine ◽  
Breeding Value ◽  
Rust Disease ◽  
Fusiform Rust ◽  
Improvement Programs ◽  
Half Diallel

Abstract The best 6 of 21 progeny-tested first-generation slash pine selections were crossed in a half diallel to study inheritance patterns of their superior fusiform rust resistance (5 trees) and height (1 tree). Their six first-test progenies were duplicated and included in the study. These two groups of progenies, along with two commercial check lots, were planted on an Upper Coastal Plain and a Flatwoods site in Georgia. At age 10 yr, the 15 progenies in the half diallel averaged 23% rust-infected compared with 54% for the check lots. First-test progenies averaged 30% infected. For percentage infection, the six parents differed in general combining ability (GCA) (0.01 > P > 0.001) on both test sites and in specific combining ability (0.05 > P > 0.01) on one site. GCA variation for height was significant (0.05 > P > 0.01) on one site. The parent selected for height had the highest breeding value for height at age 10 yr. These results show that resistance to the fusiform rust disease, a serious problem in management of the species, can be improved in slash pine. These 6 parents and their 15 progenies in the half-diallel cross are a good source of rust resistance genes for use in slash pine improvement programs. South. J. Appl. For. 20(3):143-147.

scholarly journals F-16 turbofan engine monitoring system

2019 ◽  
Vol 177 (2) ◽  
pp. 23-35
Author(s):  
Sławomir SZRAMA
Keyword(s):  
Monitoring System ◽  
Health Management ◽  
Engine Performance ◽  
Turbofan Engine ◽  
Turbofan Engines ◽  
Maintenance System ◽  
Management Concept ◽  
And Performance ◽  
Engine Maintenance ◽  
Engine Reliability

The multirole F-16 is the most advanced aircraft in the Polish Air Forces. It has been equipped with the very modern, sophisticated and advanced turbofan engine F100-PW-229. Due to the fact, that there is only one engine, its reliability, durability, efficiency and performance are the crucial factors for the safety reasons. In the article author researched maintenance system of the F100 turbofan engines, to describe Engine Monitoring System features. Engine Monitoring System (EMS) is the key element in the engine prognostic and health monitoring. The EMS provides engine fault indicators to the pilots and technicians and with the engine performance trending affects the F-16 flight safety risk and enhanced engine maintenance management concept. The main goal of this article was to provide information on the F-16 Engine Monitoring System and its impact on the aircraft airworthiness and F-16 fleet readiness resulting from the engine reliability. It is also an introduction to the F-16 Engine Health Management concept.

Fluidic Injection Thrust Reverser System for High Bypass Ratio Turbofan Engines: Experimental Model

2020 ◽  
Author(s):  
Raghav Kumar ◽  
Pankaj Rajput ◽  
Sunil Kumar
Keyword(s):  
Experimental Model ◽  
Computational Analysis ◽  
Core Flow ◽  
Turbofan Engines ◽  
The Core ◽  
Engine Thrust ◽  
3D Printed ◽  
Heavy Loads ◽  
Thrust Reverser ◽  
Bypass Ratio

Abstract Conventional thrust reversers involve the usage of mechanical blockers which are bulky as they are designed to sustain heavy loads. As a result, they account for 30% of the nacelle weight (excluding the engine core). This added engine weight results in a 0.5%–1% increase in the specific fuel consumption of the aircraft. This paper advances our investigation of “Blockerless Engine Thrust Reversers” and uses it as an inspiration to optimize the system by designing an injection module (depicting an injection as a bleed from the core flow), conducting a computational analysis and demonstrating the viability of the process by building an experimental model of a 1:40 scale of a GE90 - 115B engine. A 3D printed experimental model was built after conducting an extensive parametric analysis. This model is used to demonstrate the viability of the “Fluidic Injection Thrust Reverser” (FITR) qualitatively and quantitatively.

scholarly journals The time of the first transition of the semi-Markov process in the evaluation of diesel engine operation

2011 ◽  
Vol 145 (2) ◽  
pp. 89-98
Author(s):  
Jacek RUDNICKI
Keyword(s):  
Diesel Engine ◽  
Markov Process ◽  
Markov Processes ◽  
Marine Diesel Engine ◽  
Engine Operation ◽  
Marine Diesel ◽  
Semi Markov Process ◽  
Deterioration Process ◽  
Semi Markov Processes ◽  
Engine Reliability

The paper presents the extension of the method discussed in the literature of quantitative evaluation of operation on the example of a marine engine. According to this interpretation, the engine operation can be shown as a physical quantity. In this aspect, based on the main marine diesel engine an evaluation of the usefulness of this index for the description of the engine reliability related properties has been performed. Apart from the generally used reliability indexes, it seems purposeful to consider the engine operation (as well as its functional subsystems) in the evaluative way, so that it could be described by both energy and time. In this aspect, in the analysis the semi-Markov processes theory was used that allowed a description of the concept of the model of the engine deterioration process as a random one. The problem of the time of the first transition of the semi-Markov process to a subset of specified classes of states representing particular technical and reliability-related states of engine was described in detail.

Design Feasibility of Annular Target Thrust Reversers

2012 ◽  
Author(s):  
Enaut Gonzalez-Ruiz ◽  
Tashfeen Mahmood ◽  
Vishal Sethi ◽  
Pericles Pilidis
Keyword(s):  
Engine Performance ◽  
Advisory Council ◽  
The Public ◽  
Turbofan Engines ◽  
Turbine Performance ◽  
Fluent Software ◽  
Cfd Analyses ◽  
Thrust Reverser ◽  
Reverse Thrust ◽  
Bypass Ratio

Concerns for ecological aviation products and the objective of reducing pollutants to meet ACARE (Advisory Council for Aeronautics Research in Europe) targets address, among other initiatives, the necessity of reducing the overall weight of the aircraft. One way of dealing with the problem of aircraft weight is by investigating thrust reversers. Reducing the reverser weight will have favourable effects on fuel consumption and CO2 emissions. This paper discusses the target type thrust reverser concept. This concept was proposed by NASA and has a potential of reducing the reverser weight on future high bypass ratio turbofan engines. A feasibility study of the annular target thrust reverser in terms of engine performance and reverse thrust achieved was carried out. It comprises 2D CFD analyses of the thrust reverser and the effect of the reverser on the engine performance for different deflector configurations. The turbofan engine chosen for this study is CUTS_TF (Cranfield University Twin Spool Turbo Fan) which is similar to the GE90-85B and the information available in the public domain [1] [2] is used for the engine performance analysis along with the gas turbine performance software, GasTurb 10 [3]. CFD analyses were performed using the FLUENT software [4] to investigate the thrust reverser flow dynamics at landing at maximum reverse thrust.

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