CN102116487B

CN102116487B - Method for reducing emission of CO when biofuel is combusted in aircraft remodeling biofuel combustor

Info

Publication number: CN102116487B
Application number: CN2009102445070A
Authority: CN
Inventors: 袁怡祥; 谭春青; 郭宝亭
Original assignee: Institute of Engineering Thermophysics of CAS
Current assignee: Institute of Engineering Thermophysics of CAS
Priority date: 2009-12-30
Filing date: 2009-12-30
Publication date: 2012-07-11
Anticipated expiration: 2029-12-30
Also published as: CN102116487A

Abstract

The invention discloses a method for reducing emission of tail gas CO when biofuel is combusted in an aircraft remodeling landtype combustor. The method comprises the following steps of: keeping the hole area of the combustion liner of the original combustor of an aircraft unchanged; keeping the gross area of all main combustion holes and the positions of all the main combustion holes in the direction of the axis of the main combustion holes unchanged, and increasing the number of the main combustion holes and reducing the area of each main combustion hole; and translating the positions of mixing holes downstream along the axis to the position close to the throat of the combustion liner. In the method, only the hole positions of the wall of the combustion liner and the related hole areas are changed, and the method does not depend on the working pressure and temperature of the combustor; and the method is simple, is low in cost, and is particularly suitable for reducing the emission of CO when the biofule is combusted in the aircraft remodeling landtype combustor of which the combustion liner wall is provided with the main combustion holes and the mixing holes, and is also used for other various combustors of which the combustion liner wall is provided with the main combustion holes and the mixing holes.

Description

A kind of plane remodeling bio-fuel combustion chamber reduces the method for CO discharging

Technical field

The present invention relates to the method that a kind of plane remodeling bio-fuel combustion chamber reduces the CO discharging.

Background technology

Bio-fuel is to derive from living beings (mainly being plant) through the oxygenated fuel that pyrolysis, gasification, ester exchange reaction, fermentation, alcoholysis or the like method obtains, to use in civilian, industrial occasions gradually, and civil aviaton's power is also at some bio-fuel on probation.Ground gas turbine can with bio-fuel comprise methyl alcohol, ethanol, biodiesel, pyrolysis oil, gasification tar, pyrolysis gas, biogas gasification or the like.Find all at present that with under the constant power CO discharging that boat remodeling ground gas turbine produces during for fuel with the bio-fuel and exceeds standard when being fuel with aviation kerosine or diesel oil greatly.For example Canadian Orenda Aerospace company experimentizes on the GT2500 gas turbine; Fuel used have Dynamotive bio oil, Ensyn bio oil, ethanol biodiesel, diesel oil; Fuel is preheating to 70 ℃, oepration at full load, and the result shows nitrogen oxide NO _xDischarge less, but the CO discharging discharging when then being diesel oil far above fuel.

In theory, at high temperature, catch fire, under the prerequisite that smooth combustion is secure, the oxygen that contains in the biological oxygenated fuel has reduced the needs of fuel to the oxygen in the combustion air, might promote the OH base to generate, thereby promote burning, reduces CO, UHC discharging.This favorable factor might surpass the unfavorable factor that biological oxygenated fuel latent heat of vaporization increase, viscosity increase etc. bring under some operating mode.On the other hand,, cause ignition temperature to reduce, and then influenced, make the imperfect combustion product to increase the highstrung chemical reaction velocity of temperature because many biological oxygenated fuel latent heats of vaporization are bigger than corresponding hydrocarbon fuel.Along with the change of operating mode and chamber structure, this adverse effect might surpass fuel and contain the favorable factor that oxygen brings, thereby possibly cause CO and UHC to increase.Therefore, contain the burning of oxygen bio oil in the combustion chamber, both might increase the discharging of CO, also might reduce the discharging of CO, not being both of the internal structure of this and combustion chamber flame drum, air current composition mode is closely related, and should according to circumstances make a concrete analysis of.And the design feature of general plane combustion chamber flame drum is: have primary holes (or being secondary pore, secondary discharge orifice), blending hole, a large amount of air film aperture on the wall; Primary holes and blending hole can be brought the multiply air-flow of intense impact, obstruction, cooling effect; And the cold airflow that primary holes is come in gets into the nucleus-primary zone of burning; It is more to make that the combustion chamber mean temperature descends, thereby the OH that generates is not enough, and the control of combustion reaction simultaneously step OH+CO-CO ₂Reaction rate is slack-off along with the reduction of this zone leveling temperature levels for+H, thereby has hindered with retardation the course of reaction of CO, makes not complete reaction of CO, result cause the CO of combustion tail gas to discharge and increases.

Summary of the invention

The purpose of this invention is to provide the method that a kind of plane remodeling bio-fuel combustion chamber reduces the CO discharging,

For realizing above-mentioned purpose; The present invention reduces the method that reduces the CO discharging when boat changes land gas turbine burning bio-fuel through perforate number, size and the relative position that changes on the flame combustion chamber tube wall surface, to reach the effect that increases efficiency of combustion, energy-saving and emission-reduction.

For realizing above-mentioned purpose; Plane remodeling bio-fuel provided by the invention combustion chamber reduces the technical scheme of CO discharging; It is the area that increases the number of plane combustion chamber flame drum primary holes and dwindle each primary holes; And keep the plane combustion chamber flame drum primary holes gross area constant, and keep the position on each primary holes axis direction of living in; The position of blending hole along axis to moving near burner inner liner reducing position.More excellent: the number of primary holes is 1.5～3 times of former primary holes; The position of blending hole along axis to moving to 1 centimetre to 10 centimetres away from burner inner liner reducing position axial line distance place be.

Method of the present invention does not rely on the operating pressure and the temperature of combustion chamber; Simple and clear, the operation easily of this method; Head of combustion chamber needn't design again, so this method cost is low, and is reliable; Reduce the discharging of CO when being specially adapted to plane remodeling land that the flame combustion chamber tube wall surface has primary holes and a blending hole, also can be used for tubular, rectangle, endless tube shape, annular and other all kinds combustion chambers that other burner inner liner walls have primary holes and blending hole with the burning bio-fuel.

Description of drawings

Fig. 1 is the known combustion chamber flame drum sketch map of plane.

Fig. 2 is a plane remodeling after-burner burner inner liner sketch map of the present invention.

The specific embodiment

Technical scheme of the present invention is: keep the former combustion chamber flame drum perforated area of plane constant; Keep the gross area of each primary holes (or claiming secondary pore) and the invariant position on the axis direction of living in; The number that increases primary holes is to dwindle the area of each primary holes; Make the central combustion zone receive the damp impacts of cold airflow like this, make the fuel combustion completeness increase.

Above-mentioned measure meeting makes the reflux area length in primary zone increase to some extent; Make this regional temperature level secure with the burning required time; Under the situation of size that keeps blending hole on the former flame combustion chamber tube wall surface of plane and invariable number; Move to the position of blending hole downstream near burner inner liner reducing position along axis, like this, further reduced the impact of cold airflow the combustion zone.

Below in conjunction with Fig. 1, Fig. 2 to recently describing realization of the present invention:

Fig. 1 is the known combustion chamber flame drum profile of a plane sketch map; Enclose primary holes A (or being secondary pore) along offering one on the sectional position 1 of axis direction among Fig. 1; Enclosing blending hole B along offering one on the sectional position 2 of axis direction, the combustion chamber air-flow becomes combustion tail gas discharge combustion chamber behind process burner inner liner reducing position, figure axis 4.

Fig. 2 is a plane remodeling after-burner burner inner liner profile sketch map.The present invention implements corrective measure to Fig. 1 and has just obtained Fig. 2.

Implementation process is following: the former combustion chamber flame drum perforated area of plane is constant among maintenance Fig. 1; Keep the gross area of each primary holes A (or secondary pore) and the invariant position on the axis direction of living in, increase the number of primary holes A and dwindle the area of each primary holes A.Comparison diagram 1 can be found out with Fig. 2; The number of primary holes A among Fig. 2 is more than the number of the primary holes A among Fig. 1; But the area of each primary holes A is then less than the area of the primary holes A among Fig. 1 among Fig. 2, and the gross area of the primary holes A among Fig. 2 equates with the area of primary holes A among Fig. 1.The number of more satisfactory primary holes A is increased to 1.5～3 times of the former primary holes number in plane combustion chamber; Make the central combustion zone receive the damp impacts of cold airflow like this; Make important free radical OH in the combustion reaction not by extinguishing, make the degree that reacts completely of CO and other free radicals increase.

After this measure of enforcement; The reflux area length in primary zone (being the distance between primary holes A and the blending hole B) increases to some extent; For making this regional temperature level secure with the burning required time; Under the situation of size that keeps blending hole B on the former flame combustion chamber tube wall surface of plane and invariable number, move to the position of blending hole B downstream near (Fig. 2 is along on the burner inner liner wall at 3 places, sectional position of axis direction) near the burner inner liner reducing position along axis.Comparison diagram 1 can be found out with Fig. 2; The number of blending hole B among blending hole B number among Fig. 2 and Fig. 1 is identical; And area equates; Just blending hole B is nearer apart from the reducing position among Fig. 2, and the axis centre position of more satisfactory blending hole is 1-10 centimetre apart from the axis centre position distance of burner inner liner reducing.These measures have reduced the impact of the cold airflow of primary holes and blending hole entering to burning, and go on foot through the pass key control that influences inner combustion-gas flow tissue of burner inner liner and burning transient response, thereby reach the purpose of the discharging of CO when reducing the burning bio-fuel.

Claims

1. a plane remodeling bio-fuel combustion chamber reduces the method that CO discharges; It is characterized in that: increase the number of plane combustion chamber flame drum primary holes and dwindle the area of each primary holes; And keep the plane combustion chamber flame drum primary holes gross area constant, and keep the position on each primary holes axis direction of living in; The position of blending hole along axis to moving near burner inner liner reducing position.

2. reduce the method for CO discharging according to the said plane remodeling of claim 1 bio-fuel combustion chamber, it is characterized in that: the number of primary holes increases by 1.5～3 times.

3. reduce the method for CO discharging according to the said plane of claim 1 remodeling bio-fuel combustion chamber, it is characterized in that: the position of blending hole along axis to moving to from 1 centimetre to 10 centimetres axial line distance place, the former combustion chamber flame drum reducing of plane position.