Valveless-Gas-Turbine Combustors With Pressure Gain

1958 ◽  
Author(s):  
Carroll D. Porter
Keyword(s):  
Steady Flow ◽  
Gas Turbine ◽  
Total Pressure ◽  
High Efficiency ◽  
Combustion Products ◽  
Efficiency Gain ◽  
Developmental Problems ◽  
Gas Turbine Combustors ◽  
Turbine Inlet ◽  
Gas Turbine Compressor

A valveless combustor has been developed which has been tested at one to three atmospheres of pressure. It discharged combustion products at practical turbine-inlet temperatures and at a total pressure above that of the inlet. Developmental problems encountered and results are discussed. The smooth combustor cycle, a phased system of combustor tubes and pulsation traps, achieves steady flow at the inlet and outlet of the combustor system to preserve the high efficiency of today’s turbines and compressors. The combustor will soon be tested on a gas-turbine compressor to verify efficiency gain estimates.

The ultra-high efficiency gas turbine engine, UHEGT, Part II: A numerical study on reducing the stator blade surface temperature by indexing fuel injectors and using film cooling

2020 ◽  
pp. 095765092097353
Author(s):  
Seyed M Ghoreyshi ◽  
Meinhard T Schobeiri
Keyword(s):  
Surface Temperature ◽  
Gas Turbine ◽  
Film Cooling ◽  
Total Pressure ◽  
High Efficiency ◽  
Combustion Process ◽  
Blade Surface ◽  
Turbine Engine ◽  
Fuel Injectors ◽  
Stator Blade

In the Ultra-High Efficiency Gas Turbine Engine, UHEGT (introduced in our previous studies) the combustion process is no longer contained in isolation between the compressor and turbine, rather distributed within the axial gaps before each stator row. This technology substantially increases the thermal efficiency of the engine cycle to above 45%, increases power output, and reduces turbine inlet temperature. Since the combustion process is brought into the turbine stages in UHEGT, the stator blades are exposed to high-temperature gases and can be overheated. To address this issue and reduce the temperature on the stator blade surface, two different approaches are investigated in this paper. The first is indexing (clocking) of the fuel injectors (cylindrical tubes extended from hub to shroud), in which the positions of the injectors are adjusted relative to each other and the stator blades. The second is film cooling, in which cooling holes are placed on the blade surface to bring down the temperature via coolant injection. Four configurations are designed and studied via computational fluid dynamics (CFD) to evaluate the effectiveness of the two approaches. Stator blade surface temperature (as the main objective function) along with other performance parameters such as temperature non-uniformity at rotor inlet, total pressure loss over the injectors, and total power production by rotor are evaluated for all configurations. The results show that indexing presents the most promising approach in reducing the stator blade surface temperature while producing the least amount of total pressure loss.

Assessment of the Operational Performance of Fischer-Tropsch Synthetic-Paraffinic Kerosene in a T63 Gas Turbine Compared to Conventional Jet A-1 Fuel

2009 ◽  
Author(s):  
Nigel Bester ◽  
Andy Yates
Keyword(s):  
Gas Turbine ◽  
Thermal Loading ◽  
Flame Temperature ◽  
Combustion Products ◽  
Combustion Efficiency ◽  
Efficiency Gain ◽  
Engine Efficiency ◽  
Exit Temperature ◽  
The Impact ◽  
Combustor Liner

The performance implications of operating on Synthetic-Paraffinic Kerosene (SPK) were investigated using a RR-Allison T63-A-700 Model 250-C18 B gas turbine and compared to conventional Jet A-1. The SPK was aromatic–free and possessed a greater hydrogen/carbon ratio than petroleum derived Jet A-1. The variation in aromatic content had several implications with respect to soot and NOx emissions. Reduced aromatics also implied a reduction in the radiative heat transfer to the combustor liner. A simple model was used to explore the effect of H/C ratio on the adiabatic flame temperature, the combustor exit temperature and the engine efficiency via the impact on the gas properties and these were compared to the experimental data. It was found that operation with SPK changed directionally toward improving energy extraction via a turbine and an overall efficiency gain of about 1.2% was attained with operation on SPK through increased combustion efficiency, a reduction in liner pressure loss and an improvement in the combustion products properties. A modified combustion liner was fitted to enable the thermal loading on the combustor liner to be investigated and the expected trend with the SPK fuel was confirmed and quantified.

Recirculation Effects in Gas Turbine Combustors

1975 ◽  
Vol 97 (4) ◽  
pp. 527-530 ◽  
Author(s):  
R. Kollrack ◽  
L. D. Aceto
Keyword(s):  
Thermal Effect ◽  
Gas Turbine ◽  
Residence Time ◽  
General Result ◽  
Bluff Body ◽  
Combustion Products ◽  
Inlet Temperature ◽  
Gas Turbine Combustors ◽  
End Products ◽  
Temperature Levels

An evaluation of the effects caused by recirculation of hot final combustion products into unburned or partially burned fuel/air mixtures indicates that the thermal effect predominates the combustion activity. Dilution and the introduction of active radicals produce lesser results. Internal recirculation, such as produced by swirl or bluff body stabilization, differs from external recirculation by the temperature levels of the recirculant and its composition. The net effect of recirculation is to simulate a longer residence time and/or an effective higher inlet temperature. As a general result, the end products are closer to equilibrium, specifically the CO levels are lower and the NO levels higher.

Field Experience With Gas Turbine Inlet Air Filtration

1981 ◽  
Author(s):  
M. K. Pulimood
Keyword(s):  
Gas Turbine ◽  
Field Experience ◽  
High Efficiency ◽  
Axial Compressor ◽  
Dust Particles ◽  
Air Filtration ◽  
Gas Generator ◽  
Performance Loss ◽  
Second Stage ◽  
Turbine Inlet

This paper outlines the field experience gained from the modular retrofitting of four gas turbine inlet systems with a second stage high efficiency media filter to reduce gas turbine fouling conditions. The original gas turbine inlet systems were furnished with inertial filters. Within a few thousand hours of operation considerable gas turbine performance loss had occurred. Field inspection revealed excessive fouling of the gas generator axial compressor sections, and crusty dust particle build up within the gas turbine internals and thermocouples. A second-stage high efficiency media filter was retrofitted, to capture the fine dust particles that passed through the inertial filters. Follow-up inspection of the two-stage filter systems, after about 8000 hr of operation, disclosed little indication of the engine fouling conditions that were present prior to the retrofitting.

scholarly journals Pulsating Combustion Applied to a Small Gas Turbine

1985 ◽  
Author(s):  
J. A. C. Kentfield ◽  
P. Yerneni
Keyword(s):  
Steady Flow ◽  
Gas Turbine ◽  
Stagnation Pressure ◽  
Combustion System ◽  
Gas Generator ◽  
Future Developments ◽  
Turbine Inlet ◽  
Generator Type ◽  
Improved Performance ◽  
To Receive

A description is given of, what is believed to be the first test ever made of a gas turbine in which a valveless pulsed combustor replaced the conventional steady flow combustor. It is explained that the main incentive for using a pulsed combustor in a gas turbine is to achieve a net stagnation pressure gain between the compressor outlet and the turbine inlet. Brief descriptions are given of the pulsed combustor and the adaptation of the small gas turbine, which was of the gas generator type, to receive the pulsating combustion system. Results are presented which show that the gas turbine operated successfully using the pulsed combustor and that a very small net stagnation-pressure gain was achieved. An indication is given of possible future developments which should result in improved performance.

Detection and Localization of Fouling in a Gas Turbine Compressor From Aerothermodynamic Measurements

2004 ◽  
Author(s):  
Knox T. Millsaps ◽  
Jon Baker ◽  
Jeffrey S. Patterson
Keyword(s):  
Gas Turbine ◽  
Mass Flow ◽  
Total Pressure ◽  
Axial Flow ◽  
Pressure Losses ◽  
Sensitive Parameter ◽  
Influence Coefficients ◽  
Gas Turbine Compressor ◽  
Detection And Localization ◽  
The Impact

This paper presents a new method for condition assessment of axial flow compressors that provides a tool for specifying the magnitude and location of degradation due to fouling. A simple, meanline, stage-stacking analysis is developed, which includes the impact of blade roughness on the mass flow, work coefficient, and efficiency. The performance of a baseline, three-stage compressor with hydrodynamically smooth blades is calculated. Using the baseline geometry, the influence of roughness of the blade surfaces in the front, middle and rear stages are calculated. Empirical data for the increased total pressure losses and greater turning deviation that occurs due to rough blades are used. This analysis indicates that airfoil fouling in different stages, produce characteristic aerothermodynamic signatures, and hence the faults can be localized by the magnitudes of the various influence coefficients. This analysis also predicts that the most sensitive parameter for predicting fouling in the front stages is the percentage change in mass flow and the most sensitive parameter for predicting fouling in the rear stages is the adiabatic efficiency.

scholarly journals Advantages of Air Conditioning and Supercharging an LM6000 Gas Turbine Inlet

1994 ◽  
Author(s):  
Donald A. Kolp ◽  
Harold A. Guidotti ◽  
William M. Flye
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
High Efficiency ◽  
Performance Enhancement ◽  
Heat Rate ◽  
Inlet Temperature ◽  
Factors Affecting ◽  
Subsequent Performance ◽  
Turbine Inlet ◽  
New Generation

Of all the external factors affecting a gas turbine, inlet pressure and temperature have the greatest impact on performance. The effect of inlet temperature variations is especially pronounced in the new generation of high-efficiency gas turbines typified by the 40 MW GE LM6000. A reduction of 50 F (28 C) in inlet temperature can result in a 30% increase in power and a 4.5% improvement in heat rate. An elevation increase to 5000 feet (1524 meters) above sea level decreases turbine output 17%; conversely supercharging can increase output more than 20%. This paper addresses various means of heating, cooling and supercharging LM6000 inlet air. An economic model is developed and sample cases are cited to illustrate the optimization of gas turbine inlet systems, taking into account site conditions, incremental equipment cost and subsequent performance enhancement.

Investigation of Choking and Combustion Products' Swirling Frequency Effects on Gas Turbine Compressor Blade Fractures

2013 ◽  
Vol 135 (6) ◽  
Author(s):  
E. Poursaeidi ◽  
M. Arablu ◽  
M. A. Yahya Meymandi ◽  
M. R. Mohammadi Arhani
Keyword(s):  
Mach Number ◽  
Combustion Chamber ◽  
Gas Turbine ◽  
3D Models ◽  
Combustion Products ◽  
Critical Conditions ◽  
Engine Operation ◽  
Mach Number Distribution ◽  
Combustion Flow ◽  
Gas Turbine Compressor

Premature fracture failure of blades occurred in four of a refinery's gas turbine compressors. In order to evaluate the probability of combustion instability's effects on failure of the blades; i.e., choking and chamber resonance problems, 3D models of the combustion chamber structure and combustion flow were studied with finite element and computation fluid dynamics codes, respectively. Comparison of results of combustion chamber natural frequencies with combustion swirl frequency showed that the chamber structure is not under resonance. In order to verify probability of choking, the combustion product flow's Mach number was studied. Results of the Mach number distribution showed that the flow is subsonic in the transition piece area but, due to existence of supersonic flow conditions near the swirl vanes it may become supersonic in some critical conditions. Thus, it is suggested to operators that, for avoiding choking probabilities, it is better that engine operation be maintained close to optimum design conditions. Results of simulations showed that the fracture of the blades is not due to combustion problems.

Advantages of Air Conditioning and Supercharging an LM6000 Gas Turbine Inlet

1995 ◽  
Vol 117 (3) ◽  
pp. 513-527 ◽  
Author(s):  
D. A. Kolp ◽  
W. M. Flye ◽  
H. A. Guidotti
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
High Efficiency ◽  
Performance Enhancement ◽  
Heat Rate ◽  
Inlet Temperature ◽  
Factors Affecting ◽  
Subsequent Performance ◽  
Turbine Inlet ◽  
Percent Improvement

Of all the external factors affecting a gas turbine, inlet pressure and temperature have the greatest impact on performance. The effect of inlet temperature variations is especially pronounced in the new generation of high-efficiency gas turbines typified by the 40 MW GE LM6000. A reduction of 50°F (28°C) in inlet temperature can result in a 30 percent increase in power and a 4.5 percent improvement in heat rate. An elevation increase to 5000 ft (1524 m) above sea level decreases turbine output 17 percent; conversely supercharging can increase output more than 20 percent. This paper addresses various means of heating, cooling and supercharging LM6000 inlet air. An economic model is developed and sample cases are cited to illustrate the optimization of gas turbine inlet systems, taking into account site conditions, incremental equipment cost and subsequent performance enhancement.

Accelerated Deterioration by Saltwater Ingestion in Gas Turbine Intake Air Filters

2010 ◽  
Author(s):  
Olaf Brekke ◽  
Lars E. Bakken
Keyword(s):  
Gas Turbine ◽  
Experimental Test ◽  
High Efficiency ◽  
Test Methods ◽  
Operational Performance ◽  
Air Filtration ◽  
Test Rig ◽  
Test Program ◽  
Turbine Inlet ◽  
Different Levels

There is currently no international standard for evaluating and documenting the performance of the complete gas turbine intake air system in offshore applications. Several suppliers document the performance of their filters in accordance with applicable Heating, Ventilation, and Air Conditioning (HVAC) air-filtration standards for general ventilation. These standards fail to address the offshore-specific challenges related to salt removal and moist and wet operation and cannot be used to accurately predict operational performance or life. It is therefore desirable to develop suitable test methods and standards that can be used to better predict operational performance and life before filters and complete inlet air systems are put into operation offshore. An experimental test rig has been built in the laboratory at the Norwegian University of Science and Technology (NTNU) in order to increase understanding of the fundamentals related to gas turbine inlet air filtration. This paper presents the results from an experimental test program where the test rig was used to evaluate the effect of accelerated deterioration of high-efficiency filter elements for gas turbine inlet air filtration. High-efficiency filter elements from different suppliers were deteriorated by ingesting a saltwater solution. The performance of the filters exposed to accelerated deterioration was evaluated for different levels of contamination and compared to the performance of filter elements that have accumulated comparable amounts of contaminants in offshore operation.

Sign in / Sign up

Export Citation Format

Share Document