Power plants – Combustion products used as motive fluid – With variable oxidizer control
Patent
1993-12-07
1996-02-13
Thorpe, Timothy S.
Power plants
Combustion products used as motive fluid
With variable oxidizer control
60748, F23R 314
Patent
active
054903785
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND AND SUMMARY OF THE INVENTION
The invention relates to a combustor, and, more particularly, to a gas turbine combustor having, on a head end, particularly of an annular combustion chamber, at least one fuel nozzle and at least one swirl device which can be adjusted as a function of the load for the supply of combustion air. The swirl device has, between profiles of a nozzle-coaxial annular body, radial/tangential apertures which are distributed uniformly along the circumference, and have a cross-section that is constant along its overall length, and into which inwardly extending fingers of a sleeve which can be adjusted with respect to the annular body engage.
In the case of modern combustors and combustion chamber designs for gas turbine engines, a combustion is endeavored that is as low as possible in pollutants, particularly in the primary zone of the combustion chamber. The important pollutants are: CO (carbon monoxide), NO.sub.x (nitrogen monoxide), C.sub.x H.sub.y (non-burned hydrocarbons) as well as C (carbon). It was found that a considerable reduction of all concerned pollutant emissions is achieved at a comparatively low combustion temperature of <1,900.degree. K. in combination with a comparatively high proportion of air compared to the supplied fuel.
In addition, relatively low pollutant emissions require, among other things, a uniform processing of the fuel-air mixture to be supplied to the primary zone as well as a good degree of burn-out. This is particularly true in combination with combustors which operate by means of air support as "low-pressure systems" with a high fuel atomization quality and a partially wall-side (fuel film on sleeve) and aerodynamic fuel evaporation. In this case, local undesirable fuel enrichment which may cause the forming of soot should be avoided, among others.
A combustor of this type for combustion chambers of gas turbine engines is known, for example, from German Patent Document DE-PS 24 42 895. However, without exception, the known combustor has stationary, and therefore non-controllable swirl devices for the fed combustion air. No possibility is therefore indicated in this case to master different operating conditions, such as starting, full load, idling, cruising (stationary), in a manner that is as low in pollutants as possible with respect to the corresponding required variable fuel-air flow rates.
From German Patent Document DE-OS 24 60 740, a two-zone combustion chamber concept is known with a high-temperature first combustion zone which is rich in fuel and has an approximately stoichiometric combustion and with a low-temperature second or main combustion zone which is connected axially behind the first combustion zone, is low in fuel and is therefore as low as possible in pollutants.
In the known case, there are fuel injection nozzles which can only be controlled separately for the respective combustion zones. There is no primary air feeding that can be controlled in consideration of variable operating conditions with a view to a low-pollutant "cold" combustion. Furthermore, in the known case, no swirl devices are provided by which the primary air to be fed is provided with rotational swirls and the fuel-air mixture can be processed in a homogeneous manner and an aerodynamically stable reaction zone can be built up for the combustion. In addition, such a known two-zone combustion concept is high in constructional expenditures and relatively expensive while also requiring a relatively pronounced chamber volume and a large combustion chamber length.
Furthermore, in the interest of a low pollutant combustion, combustion chamber concepts which provide a "variable chamber geometry" in order to supply combustion air and possibly mixed air by way of holes of rows of holes are high in constructional expenditures, technically complex, susceptible to disturbances and expensive. The holes can be controlled in their cross-sections in that tube sections of the flame tube jacket of the combustion chamber can be displaced relative to one another in the a
REFERENCES:
patent: 2655787 (1953-10-01), Brown
patent: 3899881 (1975-08-01), Arvin et al.
patent: 3930368 (1976-01-01), Anderson et al.
patent: 3930369 (1976-01-01), Verdouw
patent: 4263780 (1981-04-01), Stettler
patent: 4534166 (1985-08-01), Kelm et al.
patent: 4726182 (1988-02-01), Barbier et al.
patent: 4754600 (1988-07-01), Barbier et al.
patent: 4825641 (1989-05-01), Mandet et al.
patent: 4842197 (1989-06-01), Simon et al.
patent: 5357743 (1994-10-01), Zarzalis et al.
patent: 5373693 (1994-12-01), Zarzalis et al.
Berger Johann
Simon Burkhard
MTU Motoren - und Turbinen-Union Muenchen GmbH
Thorpe Timothy S.
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