scholarly journals Investigation of Micro Gas Turbine Systems for High Speed Long Loiter Tactical Unmanned Air Systems

2018 ◽  
Author(s):  
James Large ◽  
Apostolos Pesyridis
Keyword(s):  
Gas Turbine ◽  
Fuel Consumption ◽  
High Speed ◽  
Engine Performance ◽  
Operating Conditions ◽  
Turbine Engine ◽  
Micro Gas Turbine ◽  
Fan Speed ◽  
Relative Design ◽  
Design Simplicity

In this study, the on-going research into the improvement of micro-gas turbine propulsion system performance and the suitability for application as propulsion systems for small tactical UAVs (<600 kg) is investigated. The study is focused around the concept of converting existing micro turbojet engines to turbofan with the use of a continuously variable gearbox, thus maintaining a single spool configuration and relative design simplicity. This is an effort to reduce the initial engine development cost, whilst improving propulsive performance. The BMT 120 KS micro turbojet engine is selected for performance evaluation of the conversion process using gas turbine performance software, GasTurb13. The preliminary design of a matched low-pressure compressor (LPC) for the proposed engine is then performed using meanline calculation methods. According to the analysis carried out, an improvement in the converted micro gas turbine engine performance in terms of thrust and specific fuel consumption is achieved. Furthermore, with the introduction of a CVT gearbox, fan speed operation may be adjusted independently of the core, allowing increased thrust generation or better fuel consumption. Therefore, enabling a wider gamut of operating conditions and enhances the performance and scope of tactical UAV.

scholarly journals Investigation of Micro Gas Turbine Systems for High Speed Long Loiter Tactical Unmanned Air Systems

Aerospace ◽  
2019 ◽  
Vol 6 (5) ◽  
pp. 55 ◽  
Author(s):  
James Large ◽  
Apostolos Pesyridis
Keyword(s):  
Gas Turbine ◽  
Fuel Consumption ◽  
High Speed ◽  
Engine Performance ◽  
Operating Conditions ◽  
Turbine Engine ◽  
Micro Gas Turbine ◽  
Fan Speed ◽  
Relative Design ◽  
Design Simplicity

In this study, the on-going research into the improvement of micro-gas turbine propulsion system performance and the suitability for its application as propulsion systems for small tactical UAVs (<600 kg) is investigated. The study is focused around the concept of converting existing micro turbojet engines into turbofans with the use of a continuously variable gearbox, thus maintaining a single spool configuration and relative design simplicity. This is an effort to reduce the initial engine development cost, whilst improving the propulsive performance. The BMT 120 KS micro turbojet engine is selected for the performance evaluation of the conversion process using the gas turbine performance software GasTurb13. The preliminary design of a matched low-pressure compressor (LPC) for the proposed engine is then performed using meanline calculation methods. According to the analysis that is carried out, an improvement in the converted micro gas turbine engine performance, in terms of thrust and specific fuel consumption is achieved. Furthermore, with the introduction of a CVT gearbox, the fan speed operation may be adjusted independently of the core, allowing an increased thrust generation or better fuel consumption. This therefore enables a wider gamut of operating conditions and enhances the performance and scope of the tactical UAV.

Air-Standard Aerothermodynamic Analysis of Gas Turbine Engines With Wave Rotor Combustion

2009 ◽  
Vol 131 (5) ◽  
Author(s):  
M. R. Nalim ◽  
H. Li ◽  
P. Akbari
Keyword(s):  
Gas Turbine ◽  
Gas Dynamics ◽  
Engine Performance ◽  
Algebraic Model ◽  
Operating Conditions ◽  
State Variables ◽  
Wave Rotor ◽  
Turbine Engine ◽  
Fill Fraction ◽  
Wave Compression

The wave rotor combustor can significantly improve gas turbine engine performance by implementing constant-volume combustion. The periodically open and closed combustor complicates thermodynamic analysis. Key cycle parameters depend on complex gas dynamics. In this study, a consistent air-standard aerothermodynamic model with variable specific heat is established. An algebraic model of the dominant gas dynamics estimates fill fraction and internal wave compression for typical port designs, using a relevant flow Mach number to represent wave amplitudes. Nonlinear equations for thermodynamic state variables are solved numerically by Newton–Raphson iteration. Performance measures and key operating conditions are predicted, and a quasi-one-dimensional computational model is used to evaluate the usefulness of the algebraic model.

Low Cycle Fatigue Counter

1980 ◽  
Vol 52 (6) ◽  
pp. 21-22
Keyword(s):  
Gas Turbine ◽  
High Speed ◽  
Low Cycle Fatigue ◽  
Engine Performance ◽  
Gas Turbine Engine ◽  
Rotating Machinery ◽  
Cycle Fatigue ◽  
Turbine Engine ◽  
On Demand ◽  
Long Life

The modern aircraft gas turbine engine produces power on demand hour upon hour and day in, day out. It is one of the most extensively used types of high‐speed rotating machinery as well as one of the most efficient converters of fuel into thrust. Reliability and long life with minimum maintenance depend on efficient monitoring of engine performance and component status.

Air-Standard Aerothermodynamic Analysis of Gas Turbine Engines With Wave Rotor Combustion

2009 ◽  
Author(s):  
Razi Nalim ◽  
Hongwei Li ◽  
Pezhman Akbari
Keyword(s):  
Gas Turbine ◽  
Gas Dynamics ◽  
Engine Performance ◽  
Algebraic Model ◽  
Operating Conditions ◽  
State Variables ◽  
Wave Rotor ◽  
Turbine Engine ◽  
Compression And Expansion ◽  
Wave Compression

The wave rotor combustor can significantly improve gas turbine engine performance by implementing constant-volume combustion. The periodically open and closed combustor complicates thermodynamic analysis, and key cycle parameters depend on complex gas dynamics. In this study, a consistent air-standard aerothermodynamic model with variable specific heat is established. An algebraic model of the dominant gas dynamics estimates fill fraction and internal wave compression for typical port designs, using a relevant flow Mach number to represent wave amplitudes of compression and expansion. Nonlinear equations for thermodynamic state variables are solved numerically by Newton-Raphson iteration. Performance measures and key operating conditions are predicted, and a quasi-one-dimensional computational model is used to evaluate the usefulness of the algebraic model.

scholarly journals Wave-Rotor-Enhanced Gas Turbine Engines

1997 ◽  
Vol 119 (2) ◽  
pp. 469-477 ◽  
Author(s):  
G. E. Welch ◽  
S. M. Jones ◽  
D. E. Paxson
Keyword(s):  
Gas Turbine ◽  
Fuel Consumption ◽  
Engine Performance ◽  
Specific Fuel Consumption ◽  
Specific Power ◽  
Inlet Temperature ◽  
Wave Rotor ◽  
Performance Levels ◽  
Turbine Engine ◽  
The Impact

The benefits of wave rotor topping in small (300- to 500-kW [400- to 700-hp] class) and intermediate (2000- to 3000-kw [3000- to 4000-hp] class) turboshaft engines, and large (350- to 450-kN [80,000- to 100,000-lbf] class) high-bypass-ratio turbofan engines are evaluated. Wave rotor performance levels are calculated using a one-dimensional design/analysis code. Baseline and wave-rotor-enhanced engine performance levels are obtained from a cycle deck in which the wave rotor is represented as a burner with pressure gain. Wave rotor topping is shown to enhance the specific fuel consumption and specific power of small- and intermediate-sized turboshaft engines significantly. The specific fuel consumption of the wave-rotor-enhanced large turbofan engine can be reduced while it operates at a significantly reduced turbine inlet temperature. The wave-rotor-enhanced engine is shown to behave off-design like a conventional engine. Discussion concerning the impact of the wave rotor/gas turbine engine integration identifies technical challenges.

Measured Effects of Flow Leakage on the Performance of the GT-225 Automotive Gas Turbine Engine

1980 ◽  
Vol 102 (1) ◽  
pp. 14-18 ◽  
Author(s):  
C. C. Matthews
Keyword(s):  
Gas Turbine ◽  
Fuel Consumption ◽  
Engine Performance ◽  
Performance Data ◽  
Inlet Temperature ◽  
Turbine Inlet Temperature ◽  
Cold Surface ◽  
Turbine Engine ◽  
Turbine Inlet ◽  
Hot Surface

A GT-225 regenerative gas turbine engine was used to obtain engine performance data with varied rates of simulated internal leakage. Regenerator hot surface rim and crossarm seal leaks as well as regenerator cold surface seal leaks were simulated. Instrumentation was included in external ducting to measure the leakage rates. Data were taken at three gasifier turbine speeds with turbine inlet temperature held constant by means of the variable power turbine nozzle and also with varied turbine inlet temperatures resulting from operation with the nozzle fixed at the design area. Component performance data were calculated from the engine measurements to determine the loss mechanisms associated with the leakage. The GT-225 was most sensitive to hot surface rim seal leakage, followed closely by the hot surface crossarm seal leakage, and then the cold surface leakage. Performance was degraded much more when turbine inlet temperature was fixed (by about a factor of three for specific fuel consumption) than for the fixed geometry mode. The effects of leakage became less severe as gasifier turbine speed was increased. The engine performance deterioration due simply to the flow bypass is compounded by induced losses in regenerator and compressor performance leading to very large changes in engine performance, e.g., specific fuel consumption increased up to 80 percent and power decreased as much as 40 percent with 8 percent additional leakage.

Design and Performance Measurements of a 6 kW High-Speed Micro Gas Turbine Prototype

2015 ◽  
Author(s):  
Aki Grönman ◽  
Juha Honkatukia ◽  
Petri Sallinen ◽  
Jari Backman ◽  
Antti Uusitalo ◽  
...  
Keyword(s):  
Gas Turbine ◽  
Fuel Consumption ◽  
High Speed ◽  
Weight Ratio ◽  
Good Alternative ◽  
Specific Fuel Consumption ◽  
Performance Measurements ◽  
Jet Engine ◽  
Micro Gas Turbine ◽  
And Performance

Small portable electricity generating systems are suitable in remote locations where the access by vehicles is restricted or not even possible. These kind of places include for example catastrophic areas after earthquakes or tropical cyclones. Such machines can also be used as auxiliary power units in motor or sail boats. Gas turbine based electricity generation systems offer a good alternative for typical engine-generator units which are characterized by lower specific powers. It is suggested that the power to weight ratio of a 6 kW micro gas turbine can be more than eight times higher than that of the corresponding engine-generator unit. The biggest drawback is the higher specific fuel consumption; however, by introducing a recuperator, the specific fuel consumption can be improved. In this article, the design process and experiments of a 6 kW micro gas turbine prototype are described and discussed in detail. The built non-recuperated prototype is based on a commercial, small jet engine originally designed to give thrust to radio controlled model airplanes. The jet nozzle of the jet engine was replaced by an axial power turbine which was directly connected to a small, high speed permanent magnet generator. The experiments showed the potential of the prototype.

Sign in / Sign up

Export Citation Format

Share Document