Improvements to the Performance of a Prototype Pulse, Pressure-Gain, Gas Turbine Combustor

1990 ◽  
Vol 112 (1) ◽  
pp. 67-72 ◽  
Author(s):  
J. A. C. Kentfield ◽  
L. C. V. Fernandes
Keyword(s):  
Secondary Flow ◽  
Gas Turbine ◽  
Pulse Pressure ◽  
Path Length ◽  
Flow Path ◽  
Maximum Pressure ◽  
Gas Turbine Combustor ◽  
Flow Passage ◽  
Delivery Pressure ◽  
Flow Path Length

A description is given of a simple, prototype, pulse, pressure-gain combustor for a gas turbine. The work reported was targeted at alleviating problems previously observed with the prototype combustor. These were related to irreversibilities, causing a performance deficiency, in the secondary flow passage. The work consisted of investigating experimentally the effect of tuning the secondary-flow path length, adding a flow restrictor at the combining-cone entry station, and redesigning the combining cone itself. The overall result was to eradicate the previously noted performance deficiency, thereby increasing the maximum pressure gain obtained in the gas turbine from 1.6 to 4.0 percent of the compressor absolute delivery pressure.

scholarly journals Improvements to the Performance of a Prototype Pulse, Pressure Gain, Gas-Turbine Combustor

1989 ◽  
Author(s):  
J. A. C. Kentfield ◽  
L. C. V. Fernandes
Keyword(s):  
Secondary Flow ◽  
Gas Turbine ◽  
Pulse Pressure ◽  
Path Length ◽  
Flow Path ◽  
Maximum Pressure ◽  
Gas Turbine Combustor ◽  
Flow Passage ◽  
Delivery Pressure ◽  
Flow Path Length

A description is given of a simple, prototype, pulse, pressure-gain, combustor for a gas turbine. The work reported was targeted at alleviating problems previously observed with the prototype combustor. These were related to irreversibilities, causing a performance deficiency, in the secondary flow passage. The work consisted of investigating experimentally the effect of tuning the secondary-flow path-length, adding a flow restrictor at the combining-cone entry station and redesigning the combining-cone itself. The overall result was to eradicate the previously noted performance deficiency thereby increasing the maximum pressure-gain obtained in the gas turbine from 1.6% to 4.0% of the compressor absolute delivery pressure.

Characteristics of Volcanic Ash in a Gas Turbine Combustor and Nozzle Guide Vanes

2018 ◽  
Vol 140 (7) ◽  
Author(s):  
Lei-Yong Jiang ◽  
Yinghua Han ◽  
Prakash Patnaik
Keyword(s):  
Gas Turbine ◽  
Volcanic Ash ◽  
Inlet Temperature ◽  
Gas Turbine Combustor ◽  
Flow Passage ◽  
Guide Vanes ◽  
Cooling Flow ◽  
Cooling Passage ◽  
Nozzle Guide ◽  
Nozzle Guide Vanes

To understand the physics of volcanic ash impact on gas turbine hot-components and develop much-needed tools for engine design and fleet management, the behaviors of volcanic ash in a gas turbine combustor and nozzle guide vanes (NGV) have been numerically investigated. High-fidelity numerical models are generated, and volcanic ash sample, physical, and thermal properties are identified. A simple critical particle viscosity—critical wall temperature model is proposed and implemented in all simulations to account for ash particles bouncing off or sticking on metal walls. The results indicate that due to the particle inertia and combustor geometry, the volcanic ash concentration in the NGV cooling passage generally increases with ash size and density, and is less sensitive to inlet velocity. It can reach three times as high as that at the air inlet for the engine conditions and ash properties investigated. More importantly, a large number of the ash particles entering the NGV cooling chamber are trapped in the cooling flow passage for all four turbine inlet temperature conditions. This may reveal another volcanic ash damage mechanism originated from engine cooling flow passage. Finally, some suggestions are recommended for further research and development in this challenging field. To the best of our knowledge, it is the first study on detailed ash behaviors inside practical gas turbine hot-components in the open literature.

Research on Longitudinal Slope of Highway Based on Control by Flow Path Length

2012 ◽  
Vol 178-181 ◽  
pp. 1672-1675
Author(s):  
Zhuo Zhang ◽  
Jian Ping Gao
Keyword(s):  
Linear Regression ◽  
Path Length ◽  
Flow Path ◽  
Regression Method ◽  
Linear Regression Method ◽  
Mechanical Theory ◽  
Multiple Linear Regression Method ◽  
Straight Line ◽  
Longitudinal Slope ◽  
Flow Path Length

Flow path on the highway is longer, driving exits the more dangerous. Based on the mechanical theory, the calculation models of the flow path length in different sections were built by FDM and multiple linear regression method. The flow path length of different section and different longitudinal slope was studied. The results show that: in addition to straight line and circle curve, when the number of lane is more than 4 and longitudinal slope is greater than 4%, the flow path length at other sections almost exceeded the prescribed value. Made the flow path length as control index, the amendment value on the maximum longitudinal slope of highway is proposed.

Experimental Analysis of Combustion in Gas Turbine

2019 ◽  
Author(s):  
M. S. N. Murthy ◽  
Subhash Kumar ◽  
Sheshadri Sreedhara
Keyword(s):  
Gas Turbine ◽  
Flow Rate ◽  
Experimental Analysis ◽  
Air Flow ◽  
Measuring System ◽  
Maximum Pressure ◽  
Gear Pump ◽  
Air Flow Rate ◽  
Gas Turbine Combustor ◽  
Turbine Engine

Abstract This paper presents the methodology and results of an experimental analysis of combustion in a gas turbine combustor. The experimental setup is designed to imitate the conditions of a working gas turbine engine (GT), using an actual gas turbine combustor. Air is supplied by a heavy-duty air compressor at a maximum pressure of 7 bar to the combustor through an air pipe catering to the developing length. The air flow rate is measured using an ASME standard Venturimeter along with a manometer. The air flow rate and pressure are controlled by a combination of air outlet valve placed before developing length and by a throttle orifice in the exhaust duct at combustor outlet. Diesel fuel used in the experiments is provided at required atomizing pressure by a gear pump. Mass flow rate and pressure of fuel is controlled by combination of valves and varying the speed of gear pump using a variable speed electric motor. Combustion is initiated in a conventional pilot ignition unit using a spark plug and fuel burner. Fuel flow rate is measured accurately using a unique catch and time measuring system at the inlet of the gear pump.

Thermal Behavior of Radial Foil Bearings Supporting an Oil-Free Gas Turbine: Design of the Cooling Flow Passage and Modeling of the Thermal System

2017 ◽  
Vol 139 (6) ◽  
Author(s):  
Donghyun Lee ◽  
Hyungsoo Lim ◽  
Bumseog Choi ◽  
Byungok Kim ◽  
Junyoung Park ◽  
...  
Keyword(s):  
Secondary Flow ◽  
Gas Turbine ◽  
Air Flow ◽  
Successful Implementation ◽  
Flow Passage ◽  
Foil Bearings ◽  
Operation Speed ◽  
Bearing Sleeve ◽  
Cooling Air Flow ◽  
Cooling Air

Gas foil bearings (GFBs) have many noticeable advantages over the conventional rigid gas bearings, such as frictional damping of the compliance structure and tolerance to the rotor misalignment, so they have been successfully adopted as the key element that makes possible oil-free turbomachinery. As the adoption of the GFB increases, one of the critical elements for its successful implementation is thermal management. Even though heat generation inside the GFB is small due to the low viscosity of the lubricant, many researchers have reported that the system might fail without an appropriate cooling mechanism. The objective of the current research is to demonstrate the reliability of GFBs installed in the hot section of a micro-gas turbine (MGT). For the cooling of the GFBs, we designed a secondary flow passage and thermohydrodynamic (THD) analysis has been done for temperature prediction. In the analysis, the 3D THD model for the radial GFB extended to include the surrounding structure, such as the plenum, chamber, and the rotor in the solution domain by solving global mass and energy balance equations. In the MGT, the pressurized air discharged from the compressor wheel was used as the cooling air source, and it was injected into the plenum between two radial GFBs. We monitored the pressure and temperature of the cooling air along the secondary flow passage during the MGT operation. No thermal instability occurred up to the maximum operation speed of 43,000 rpm. The test results also showed that the pressure drop between the main reservoir and the plenum increases with an increasing operation speed, which indicated an increased cooling air flow into the plenum. The plenum and bearing sleeve temperature was maintained close to the cooling air source temperature for the entire speed due to a sufficient cooling air flow into the bearing. In addition, the direct injection of the cooling air from the main stream lowered the bearing sleeve temperature by 5–20 °C over the injection through the reservoirs. The predicted plenum and bearing sleeve temperatures with the developed THD model show good agreement with the test data.

scholarly journals Further Development of an Improved Pulse, Pressure Gain, Gas-Turbine Combustor

1990 ◽  
Author(s):  
J. A. C. Kentfield ◽  
L. C. V. Fernandes
Keyword(s):  
Secondary Flow ◽  
Steady Flow ◽  
Gas Turbine ◽  
Pulse Pressure ◽  
Gas Turbines ◽  
Gas Generator ◽  
Pulse Combustor ◽  
Analytical Work ◽  
Further Development ◽  
Flow Duct

Further development work is described, which included both theoretical analysis and experimental testing, of an improved prototype, valveless, pulse, pressure gain, combustor for gas turbines. The analytical work involved the application to the non-steady flow in the combustor secondary flow duct of the method-of-characteristics as used for one-space dimensional, time dependent, compressible flows. Gas temperatures in the secondary flow duct were measured experimentally as were the pressure gain, due to the pulse combustor, and the overall efficiencies of the gas generator type gas-turbine with both the conventional steady flow combustor and the alternative pulse, pressure gain, combustor. It was concluded that the analytical work confirmed earlier experimental findings showing the benefits of restricting the secondary flow duct exit area. It was also concluded that the use of the pulse combustor resulted in a maximum improvement of 27% in the thermal efficiency of the small, low pressure-ratio, educational, gas generator turbo-machine.

Numerical Investigation of Flow and Heat Transfer in Gas Turbine Serpentine Passage Cooling and Comparison With Experimental Data

2013 ◽  
Author(s):  
S. Kathiravan ◽  
Roberto De Prosperis ◽  
Alessandro Ciani
Keyword(s):  
Heat Transfer ◽  
Secondary Flow ◽  
Gas Turbine ◽  
Turbine Blade ◽  
Physical Phenomenon ◽  
Flow Path ◽  
Heat Transfer Analysis ◽  
Gas Turbine Blade ◽  
Cooling Flow ◽  
The Impact

Due to recent advancements made in computational technology, CFD tools are capable of accurately capturing complex physical phenomenon. The proposed novel CFD methodology improves the prediction reliability and capability of Gas Turbine Blade heat transfer and secondary flow behaviour. This paper discusses a robust CFD based methodology to validate the complex gas turbine blade cooling design using detailed 3D flow & conjugate heat transfer analysis. Both primary and secondary flow domains along with blade metal are considered in one single integrated CFD model. This will capture the coupled heat transfer and tip vortices mixing effects and hence accurately predict the secondary cooling flow. The secondary flow path geometry consists of serpentine passages with turbulator features in the flow path to improve the effective heat transfer. Several sensitivity studies were performed using the above model to understand the impact of turbulator fillets, tip hole coating thickness, domain interface and suitably accounted for in the full scale simulation. The numerical simulation results were extensively validated with GE industrial Frame5 gas turbine prototype test thermocouple data and thermal profiles (span-wise) obtained from metallographic images. This novel method gives a thorough understanding of flow-thermal physics involved in serpentine cooling and helps to optimize effective cooling flow usage.

Sign in / Sign up

Export Citation Format

Share Document