Performance Characteristics of Brush Seals for Limited-Life Engines

1993 ◽  
Vol 115 (2) ◽  
pp. 390-396 ◽  
Author(s):  
R. E. Chupp ◽  
C. A. Dowler
Keyword(s):  
Gas Turbine ◽  
Engine Performance ◽  
Performance Characteristics ◽  
Turbine Engines ◽  
Gas Turbine Engines ◽  
Labyrinth Seals ◽  
Performance Improvements ◽  
Limited Life ◽  
In Series ◽  
Brush Seals

Brush seals are potential replacements for air-to-air labyrinth seals in gas turbine engines. An investigation has been conducted to determine the performance characteristics of brush seals for application in limited-life gas turbine engines. An elevated temperature, rotating test rig was designed and built to test labyrinth and brush seals in simulated subsonic and supersonic engine conditions. Results from initial tests for subsonic applications demonstrated that brush seals exhibit appreciably lower leakage compared to labyrinth seals, and thus offer significant engine performance improvements. Performance results have been obtained showing the effect of various brush seal parameters, including: initial interference, backplate gap, and multiple brush seals in series.

scholarly journals Performance Characteristics of Brush Seals for Limited-Life Engines

1991 ◽  
Author(s):  
Raymond E. Chupp ◽  
Constance A. Dowler
Keyword(s):  
Gas Turbine ◽  
Engine Performance ◽  
Performance Characteristics ◽  
Turbine Engines ◽  
Gas Turbine Engines ◽  
Labyrinth Seals ◽  
Performance Improvements ◽  
Limited Life ◽  
In Series ◽  
Brush Seals

Brush seals are potential replacements for air-to-air labyrinth seals in gas turbine engines. An investigation has been conducted to determine the performance characteristics of brush seals for application in limited-life gas turbine engines. An elevated temperature, rotating test rig was designed and built to test labyrinth and brush seals in simulated subsonic and supersonic engine conditions. Results from initial tests for subsonic applications demonstrated that brush seals exhibit appreciably lower leakage compared to labyrinth seals, and thus offer significant engine performance improvements. Performance results have been obtained showing the effect of various brush seal parameters including: initial interference, backplate gap and multiple brush seals in series.

Design, Development and Application of Vehicle Gas Turbine Engines

1966 ◽  
Vol 181 (1) ◽  
pp. 149-172
Author(s):  
P. A. Phillips ◽  
Peter Spear
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
Low Cost ◽  
Engine Performance ◽  
Turbine Engines ◽  
Gas Turbine Engines ◽  
Design Development ◽  
Turbine Engine ◽  
Wide Range ◽  
Cycle Temperature

After briefly summarizing worldwide automotive gas turbine activity, the paper analyses the power plant requirements of a wide range of vehicle applications in order to formulate the design criteria for acceptable vehicle gas turbines. Ample data are available on the thermodynamic merits of various gas turbine cycles; however, the low cost of its piston engine competitor tends to eliminate all but the simplest cycles from vehicle gas turbine considerations. In order to improve the part load fuel economy, some complexity is inevitable, but this is limited to the addition of a glass ceramic regenerator in the 150 b.h.p. engine which is described in some detail. The alternative further complications necessary to achieve satisfactory vehicle response at various power/weight ratios are examined. Further improvement in engine performance will come by increasing the maximum cycle temperature. This can be achieved at lower cost by the extension of the use of ceramics. The paper is intended to stimulate the design application of the gas turbine engine.

On-Line Detergent Washing: Reducing the Environmental Effects on the LCAC Gas Turbine Engines

1992 ◽  
Author(s):  
Jeffrey S. Patterson ◽  
Soren K. Spring
Keyword(s):  
Gas Turbine ◽  
Systems Engineering ◽  
Present Method ◽  
Engine Performance ◽  
Turbine Engines ◽  
Harsh Environment ◽  
Gas Turbine Engines ◽  
Test Results ◽  
On Line ◽  
Air Cushion

The Landing Craft Air Cushion (LCAC) gas turbine engines operate in an extremely harsh environment and are exposed to excessive amounts of foreign contaminants. The present method of crank washing is effective when properly performed, but is labor intensive and increases craft downtime. Naval Ship Systems Engineering Station (NAVSSES) designed and installed a prototype on-line detergent wash system which reduced maintenance and craft downtime. Initial test results indicated that the system reduced engine performance degradation and corrosion.

Component Integration and Loss Sources in 3 – 5 kW Gas Turbines

2005 ◽  
Author(s):  
M. A. Monroe ◽  
A. H. Epstein ◽  
H. Kumakura ◽  
K. Isomura
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
Large Scale ◽  
Engine Performance ◽  
Turbine Engines ◽  
Gas Turbine Engines ◽  
Flow Distortion ◽  
Thermal Isolation ◽  
Component Integration ◽  
Measured Efficiency

The performance of a regenerated gas turbine generator in the 3–5 kW power range has been analyzed to understand why its measured efficiency was on the order of 6% rather than the 20% suggested by consideration of its components’ efficiencies as measured on rigs. This research suggests that this discrepancy can be primarily attributed to heat and fluid leaks not normally considered in the analysis of large gas turbine engines because they are not as important at large scale. In particular, fluid leaks among the components and heat leakage from the hot section into the compressor flow path contributed the largest debits to the engine performance. Such factors can become more important as the engine size is reduced. Other non-ideal effects reducing engine performance include temperature flow distortion at the entrance to both the compressor and turbine. A cycle calculation including all of the above effects matched measured engine data. It suggests that relatively simple changes such as thermal isolation and leak sealing can increase both power output and efficiency of this engine, over 225% in the latter case. The validity of this analysis was demonstrated on an engine in which partial thermal isolation and improved sealing resulted in a more than 40% increase in engine output power.

scholarly journals Study on the Influence of Air Bleeds on the Behaviour and on the Performance of Gas Turbine Engines

1991 ◽  
Author(s):  
Giovanni Torella
Keyword(s):  
Gas Turbine ◽  
Fault Simulation ◽  
Engine Performance ◽  
Thermodynamic Characteristics ◽  
Computer Programs ◽  
Turbine Engines ◽  
Gas Turbine Engines ◽  
Design Codes ◽  
Design Point ◽  
Air System

The influence of air system an engine performance and behaviour is considered. A method based on the polytropic efficiency concept has been developed in order to calculate the thermodynamic characteristics of air bleed. This method has been included in the “Design Point” and “Off Design” codes of different configuration engines. The paper shows the wide applications of the programs for several calculations. Moreover the results of the faults of air system are shown by both diagnostic and fault simulation computer programs.

scholarly journals Aircraft Gas Turbine Engine Testing

2019 ◽  
pp. 39-44
Author(s):  
Stanislav Fábry ◽  
Miroslav Spodniak ◽  
Peter Gašparovič ◽  
Peter Koščák
Keyword(s):  
Gas Turbine ◽  
Engine Performance ◽  
Turbine Engines ◽  
Gas Turbine Engines ◽  
Test Cycle ◽  
Turbine Engine ◽  
Testing Sequence ◽  
Prerequisite Knowledge ◽  
Engine Testing ◽  
Special Factors

The paper deals with testing of aircraft gas turbine engines. The main goal of the research is to propose and design testing sequence for a new or rebuilt engine. All factors and circumstances are described, including surroundings of the engine under test. Prerequisite knowledge is introduced, including the theory of testing, description of test beds, the methods of measurement of engine parameters and special factors that affect engine performance. Some examples of real testing facilities are mentioned. The result of the work is a proposal of test cycle, that can be modified according to engine purpose and specification.

scholarly journals МЕТОД РАСЧЕТА ТЕРМОГАЗОДИНАМИЧЕСКИХ ПАРАМЕТРОВ ТУРБОВАЛЬНОГО ГТД НА ОСНОВЕ ПОВЕНЦОВОГО ОПИСАНИЯ ЛОПАТОЧНЫХ МАШИН. ЧАСТЬ 1. ОСНОВНЫЕ УРАВНЕНИЯ

2018 ◽  
pp. 48-58
Author(s):  
Людмила Георгиевна Бойко ◽  
Олег Владимирович Кислов ◽  
Наталия Владимировна Пижанкова
Keyword(s):  
Gas Turbine ◽  
Flow Rate ◽  
Pressure Ratio ◽  
Turbine Engines ◽  
Geometrical Parameters ◽  
Gas Turbine Engines ◽  
Balance Equations ◽  
Wide Range ◽  
In Series ◽  
Multistage Compressor

Gas turbine engines processes mathematic simulations are widely used in different steps of its living cycle. All engine simulations may be divided into different difficulty levels: higher simulation level allows doing a more pre­cise description of physical processes in main units of gas turbine engines and their elements. It gives the oppor­tunity for getting better arrangement of calculation results and experimental data, reduce the quality of factors, which are traditionally used in determine engine operational characteristics with 1-level models.The purpose of the article is to describe the thermogasdynamic parameters and maintenance perfomances cal­culation method, which based on second level mathematic simulation. Its main feature is blade-to-blade turbomachines description (multistage compressor and multistage cooling gas turbine), which allows to take into account blade and flow path geometrical parameters. Their changing during the gas turbine engine design and de­velopment processes influence its performances: thrust, fuel consumption, efficiency as functions of values of flow rate, rotational speed, engine entrance conditions and so on. All these dependences could be defined by using proposed calculation method.In distinction from methods which are noted, this method allows to concede compressor or turbine incidence angles, drag values, pressure ratio, surge margin in design and off-design  engine regimes. The opportunity to take into account by-passing and air bleeding from compressor blade channels and their engine parameters influence is very important also.The article includes calculation method main points, block-scheme, equations system, which gives the opportunity of alignment the engine units and their elements in wide range of state working regimes. Set of equations consists of flow rate balance equations through the stages of multistage compressor and turbine, combustion chamber and connected channels. Also system includes power balance equations, by-passing, air bleeding from compressor stages channels, its admission into the cooling turbine stages and ac­counts their thermodynamic parameters. Compressors and turbines maps parameters are calculated with main turbomachinery theory lows and semi-empirical dependences.This article is the first in series of articles, which considers this problem

Problems and Use of the Scaling Factors in the Numerical Simulation of Jet Engines

1990 ◽  
Author(s):  
G. Torella
Keyword(s):  
Numerical Simulation ◽  
Trend Analysis ◽  
Gas Turbine ◽  
Engine Performance ◽  
Turbine Engines ◽  
Gas Turbine Engines ◽  
Jet Engines ◽  
Scaling Factors ◽  
Operational Life

The possibility of the use of scaling factors in the calculations and in the simulation of gas turbine engines have been considered. Application of this technique to the simulation of trend analysis, the evaluation of the component maps shifting during the operational life of the engine and the calculation of matrices of influence have been presented. Moreover, some problems related to the use of scaling factors have been studied and their effects on the engine performance have been presented.

Utilisation of Bio-Fuels in Aviation Gas-Turbine Engines: An Experimental and Theoretical Evaluation

2009 ◽  
Author(s):  
Jason Cromarty ◽  
Sylvester Abanteriba
Keyword(s):  
Gas Turbine ◽  
Engine Performance ◽  
Theoretical Modelling ◽  
Turbine Engines ◽  
Mustard Seed ◽  
Gas Turbine Engines ◽  
Fuel Production ◽  
Theoretical Evaluation ◽  
Technical Issues ◽  
Blend Ratios

An experimental and theoretical investigation was undertaken to identify and evaluate the key technical issues surrounding the ‘drop-in’ utilisation of alternative bio-fuels in aviation gas-turbine propulsion systems. Region-suitable biofuels were identified and suitability evaluated based on the following three criteria: ‘drop-in’ capability, environmental and economic sustainability and industrialisation prospects. Bio-fuel engine performance will be evaluated based on the specific fuel consumption, specific thrust, nature and quantity of emissions through theoretical modelling. This paper outlines a variety of different bio-fuel type options that were investigated. By using engineering and scientific methodology the fuels were evaluated to verify their suitability for gas-turbine aviation use. The eventual bio-fuel selected for further evaluation was a locally produced mustard seed oil derivative bio-fuel which was blended at various blend ratios with standard Jet A-1 turbine fuel. Verification testing processes for future investigation are detailed. In addition to engine performance evaluation endeavours, this paper also seeks to address and offer recommendations in the areas of bio-fuel production, transport, storage, certification and emissions.

Predicting the Ultimate Performance of Advanced Power Cycles Based on Very High Temperature Gas Turbine Engines

1993 ◽  
Author(s):  
Paolo Chiesa ◽  
Stefano Consonni ◽  
Giovanni Lozza ◽  
Ennio Macchi
Keyword(s):  
Gas Turbine ◽  
Large Scale ◽  
Computer Code ◽  
Turbine Engines ◽  
Gas Turbine Engines ◽  
Gas Temperature ◽  
Clear Trend ◽  
Performance Improvements ◽  
Future Technology ◽  
The Impact

It is well known that the history of gas turbine engines has been characterized by a very clear trend toward higher and higher operating temperatures, a growth which in the past 40 years has progressed at the impressive pace of approximately 13°C/year. Expected improvements in blade cooling techniques and advancements in materials indicate that this tendency is going to last for long time, leading to firing temperatures of over 1500°C within the next two decades. This paper investigates the impact of such temperature increase on optimal cycle arrangements and on ultimate performance improvements achievable by future advanced gas/steam cycles for large-scale power generation. Performance predictions have been carried out by a modified, improved version of a computer code originally devised and calibrated for “1990 state-of-the-art” gas/steam cycles. The range of performances to be expected in the next decades has been delimited by considering various scenarios of cooling technology and materials, including the extreme situations of adiabatic expansion and stoichiometric combustion. The results of parametric thermodynamic analyses of several cycle configurations are presented for a number of technological scenarios, including cycles with intercooling and reheat. A specific section discusses how the optimum configuration of the bottoming steam cycle changes to keep up with exhaust gas temperature increases. Calculations show that, under plausible assumptions on future technology advancements, within two decades the proper selection of plant configuration and operating parameters can yield net efficiencies of over 60%.

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