The Pulsed Thermocouple for Gas Turbine Application

1977 ◽  
Vol 99 (1) ◽  
pp. 1-10 ◽  
Author(s):  
D. Kretschmer ◽  
J. Odgers ◽  
A. F. Schlader
Keyword(s):  
Exact Solution ◽  
Temperature Distribution ◽  
Gas Turbine ◽  
Temperature Rise ◽  
Measurement Accuracy ◽  
Gas Analysis ◽  
Gas Turbine Combustor ◽  
Analogue Circuit ◽  
Good Repeatability ◽  
Better Than

A mechanically pulsed suction thermocouple has been developed. The gas to be measured is sucked through a sonic orifice, thus eliminating the influence of the velocity inside the combustor. The signal from the thermocouple is processed by an analogue circuit. Contrary to the usual approach to the problem of dynamic temperature measurements (i.e., the attempt to find an exact solution to the extrapolation of the temperature rise curve) in this work, a calibration of the probe was done. This calibration showed very little scatter and a good repeatability. The overall measurement accuracy was better than ±1 percent. As a test of application, a partial survey of the temperature distribution within an aircraft gas turbine combustor was done. A satisfactory agreement was observed between temperatures measured by the thermocouple and those determined from gas analysis. In this test the pulse thermocouple proved to be a reliable and fast tool for the measurement of local gas temperatures.

Acoustic Control of Dilution-Air Mixing in a Gas Turbine Combustor

1982 ◽  
Author(s):  
P. J. Vermeulen ◽  
J. Odgers ◽  
V. Ramesh
Keyword(s):  
Temperature Distribution ◽  
Temperature Profile ◽  
Gas Turbine ◽  
Exit Plane ◽  
Gas Turbine Combustor ◽  
Acoustic Control ◽  
Air Mixing ◽  
Air Flows ◽  
Plane Temperature ◽  
Load Conditions

A small combustor of normal design employing acoustic control of the dilution-air flows has been successfully tested up to “half-load” conditions. It has been shown that this technique can be used to selectively and progressively control the exit plane temperature distribution, and the ability to trim the temperature profile has been convincingly demonstrated. The acoustic driver power requirements were minimal indicating that driver power at “full-load” will not be excessive. The nature of the acoustically modulated dilution-air flows has been clearly establish to the design of combustors such that a desired exit plane temperature distribution may be achieved.

Parametric Simulation of Turbulent Reacting Flow and Emissions in a Lean Premixed Reverse Flow Type Gas Turbine Combustor

2011 ◽  
Vol 134 (2) ◽  
Author(s):  
Daero Joung ◽  
Kang Y. Huh ◽  
Yunho An
Keyword(s):  
Temperature Distribution ◽  
Gas Turbine ◽  
Reverse Flow ◽  
Physical Models ◽  
Pollutant Emissions ◽  
Reacting Flow ◽  
Outlet Temperature ◽  
Operating Pressure ◽  
Gas Turbine Combustor ◽  
Fuel Ratio

This paper describes simulation of a small stationary gas turbine combustor of a reverse flow, semi-silo type for power generation. The premixed coherent flame model (PCFM) is applied for partially premixed methane/air with an imposed downstream flame area density (FAD) to avoid flashback and incomplete combustion. Physical models are validated against the measurements of outlet temperature, product gas composition, and NO emission at the low operating pressure. Parametric study is performed to investigate the effect of load and pilot/total (P/T) fuel ratio on mixing characteristics and the resulting temperature distribution and pollutant emissions. As the P/T fuel ratio increases, the high temperature region over 1900 K enhances reaction of the mixture from the main nozzle in the primary mixing zone. For low P/T ratios, the pilot stream dilutes the mixture, on the contrary, to suppress reaction with an increasing height of the lifted flame. The NO is associated with the unmixedness as well as the mean temperature level and tends to increase with increasing load and P/T ratio. The high operating pressure does not affect overall velocity and temperature distribution, while it tends to increase NO and liner temperature under the given boundary conditions.

Improvement of the Outlet Temperature Distribution of a Dual-Fuel Gas Turbine Combustor by a Simplified CFD Model

2012 ◽  
Author(s):  
Paolo Gobbato ◽  
Andrea Lazzaretto ◽  
Massimo Masi
Keyword(s):  
Gas Turbine ◽  
Dual Fuel ◽  
Outlet Section ◽  
Outlet Temperature ◽  
Computational Domain ◽  
Gas Turbine Combustor ◽  
Fuel Gas ◽  
Turbine Inlet ◽  
Primary Zone ◽  
Better Than

The mixing process within the dilution zone noticeably affects the temperature field in the outlet section of a gas turbine combustor. In fact, dilution jets lower the temperature of the hot flow exiting the primary zone establishing suitable temperature profile and pattern factor at the combustor outlet. Thus, the dilution zone design has a significant impact on performance and durability of the turbine. In this study, a dual-fuel gas turbine combustor is investigated by a commercial finite-volume CFD code. The computational domain extends from the compressor discharge to the gas turbine inlet and it is meshed with a coarse grid since it was originally conceived for thermoacoustic analysis. The model has been already validated throughout measurements acquired during full scale isothermal and reactive tests. On the basis of the results of reactive simulations, several solutions of the dilution zone are designed to improve the uniformity of radial and circumferential temperature at the turbine inlet. The designed configurations feature number, arrangement and diameter of dilution holes which differ from the commercial configuration providing four identical dilution holes equally spaced. Advantages and drawbacks of each dilution zone layout are supported by results of numerical calculations. The results suggest that the solutions featuring two dilution holes perform better than the actual layout.

Evaluation of a Particulate Sampling Methodology From a Gas Turbine Exhaust Using Real-Time Size and Number Analysis at Simulated Aircraft Conditions

2010 ◽  
Author(s):  
Yura A. Sevcenco ◽  
Andrew P. Crayford ◽  
Richard Marsh ◽  
Philip J. Bowen ◽  
Michael N. Miller ◽  
...  
Keyword(s):  
Particulate Matter ◽  
Gas Turbine ◽  
Steel Sample ◽  
Gas Analysis ◽  
Operating Conditions ◽  
Stainless Steel Sample ◽  
Flow State ◽  
Gas Turbine Combustor ◽  
Transport Losses ◽  
Gas Turbine Exhaust

Two differential mobility spectrometers (DMS 500) were used to measure particulate size distributions and particulate matter losses in the exhaust of a simulated gas turbine combustor test rig. The rig is a stable gas turbine combustor simulator providing particles of physicochemical properties analogous to real aircraft engines. The rig ran at three operating conditions, giving a range of organic to elemental carbon distributions, allowing different aerosol compositions to be formed for comparison and analysis of transport losses. Smoke number from a recognised filter stain method and gas analysis of the exhaust were also taken to prove representative engine conditions. The two instruments were separated by 10m of heated stainless steel sample line and a range of transitional to turbulent flow rates from 19L/min to 64L/min were utilised for the comparative analysis. The aerosols showed measureable transport losses dependant on organic fraction, while flow rate showed substantial effects dependent on the flow state within the line. Comparisons made to the particle transport loss model from United Technologies Research Center show agreement in trend losses relative to size distribution of the particulate matter, but with losses being higher than predicted.

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