Background technology
At present; along with energy scarcity and the whole world are to the attention of environmental protection problem; the requirement of various countries to gas-turbine combustion chamber discharge and efficiency of combustion is more and more stricter; General Requirements gas turbine is between 50% and above loading zone; combustion chamber discharge can maintain reduced levels, keeps higher efficiency of combustion simultaneously.In order to reach the object of low emission, premixed combustion technology is widely adopted.Therefore, need to realize the device that fuel and air are pre-mixed, i.e. fuel-air blender, and form the fuel-air mixture mixing and have certain speed type at mixer outlet place, and then enter in burner inner liner and participate in burning.
Because the mode of fuel with premixed flame in combustion chamber ejected from fuel-air blender is burnt, for reaching extremely low disposal of pollutants, flame is operated near flammable border, add that the fuel-air mixture body effluxvelocity that blender ejects is larger, the stable of flame is more difficult, in prior art solution normally centerbody axial length be less than the length of fuel-air blender outside wall surface, fuel-air mixture body is first expanded to the central area in centerbody head end wall downstream when annular premixed channel flows out, in the formation recirculating zone, central area in centerbody head end wall downstream, then expansion further in the inherent burner inner liner of burner inner liner is entered, and then in burner inner liner, form larger recirculation zone, stablizing for flame, but these two recirculation zone are subject to the influence of other air-flows in burner inner liner, flame is existed can not stablize or the risk of poor stability.
In order to improve the stability of flame, in existing patent document (CN1704574), have employed the manufacture shock air contrary with main flow flow direction near mixer outlet centerbody to flow, form recirculation eddy current, decrease the air capacity be ejected in recirculating zone, thus effluxvelocity near reduction mixer outlet, improve flame holding.And the structure processing connections such as this blender internal layer baffle plate wait comparatively complicated, and be not easy to maintain and replace, and recycle eddy current and be not easy to control, be likely difficult to solve steady fiery problem.
Therefore, for above deficiency, need a kind of stability contributing to improving flame, structure is simple, not space-constrained fuel-air blender and gas turbine.
Summary of the invention
(1) technical problem that will solve
The technical problem to be solved in the present invention there is provided a kind of fuel-air blender and gas turbine, and this fuel-air blender can realize the stability contributing to improving flame, and structure is simple, and not by the restriction in space.
(2) technical scheme
In order to solve the problems of the technologies described above, the invention provides a kind of fuel-air blender, it comprises centerbody, annular wall and swirl-flow devices, described annular wall is coaxially arranged on the periphery of centerbody, between annular wall and centerbody, form hybrid channel, described swirl-flow devices is positioned on hybrid channel and the front end of close centerbody; The end of described centerbody is provided with centerbody head end wall, the end of described annular wall is provided with annular wall end wall, be enclosed to form by the tube chamber ring wall that liquidates the tube chamber that liquidates between described centerbody head end wall and annular wall end wall, described in the tube chamber ring wall that liquidates be provided with the airflow hole that liquidates be communicated with described hybrid channel.
Wherein, described in liquidate on tube chamber ring wall and at least offer the airflow hole that liquidates for a pair, and the axial line of the airflow hole that liquidates of each centering is identical.
Wherein, described in the airflow hole that liquidates be straight hole, described in the liquidate hole shape of airflow hole be circular or oval or rectangle.
Wherein, described centerbody head end wall is provided with centerbody head end wall spray-hole, and described annular wall end wall is provided with annular wall end wall spray-hole.
Wherein, described centerbody head end wall spray-hole and annular wall end wall spray-hole are straight hole or inclined hole.
Wherein, the diameter of described centerbody head end wall is not less than the diameter of centerbody.
Wherein, the axial location of described centerbody head end wall is in the axial range of annular wall.
Wherein, described swirl-flow devices comprises the swirl vane that centrally body circumference is arranged, and described swirl vane is provided with teasehole, and described centerbody is provided with the fuel channel be communicated with teasehole.
The present invention also provides a kind of gas turbine, and it comprises described fuel-air blender.
(3) beneficial effect
Technique scheme of the present invention has following beneficial effect: the invention provides a kind of fuel-air blender, the fuel-air mixture ejected from opposed jets hole has larger momentum, paired opposed jets, after impacting mutually, realizes the mixing uniformity improving fuel air mixture further; And, in limited physical space, also can form local return district by the circumferential zones between the region of upstream, opposed jets hole and opposed jets hole, thus contribute to the stability improving flame; This fuel-air mixer structure is simple, easily realizes, and not by the restriction of combustion chamber miscellaneous part, the problem such as not to mate.
Detailed description of the invention
Below in conjunction with drawings and Examples, embodiments of the present invention are described in further detail.Following examples for illustration of the present invention, but can not be used for limiting the scope of the invention.
In describing the invention, except as otherwise noted, the implication of " multiple " is two or more; Term " on ", D score, "left", "right", " interior ", " outward ", " front end ", " rear end ", " head ", the orientation of the instruction such as " afterbody " or position relationship be based on orientation shown in the drawings or position relationship, only the present invention for convenience of description and simplified characterization, instead of indicate or imply that the device of indication or element must have specific orientation, with specific azimuth configuration and operation, therefore can not be interpreted as limitation of the present invention.In addition, term " first ", " second ", " the 3rd " etc. only for describing object, and can not be interpreted as instruction or hint relative importance.
In describing the invention, it should be noted that, unless otherwise clearly defined and limited, term " is connected ", " connection " should be interpreted broadly, such as, can be fixedly connected with, also can be removably connect, or connect integratedly; Can be mechanical connection, also can be electrical connection; Can be directly be connected, also indirectly can be connected by intermediary.For the ordinary skill in the art, concrete condition above-mentioned term concrete meaning in the present invention can be understood.
As Figure 1-3, the fuel-air blender described in the present embodiment, it comprises centerbody 1, annular wall 2 and swirl-flow devices 3, and annular wall 2 is coaxially arranged on the periphery of centerbody 1, forms hybrid channel 16 between annular wall 2 and centerbody 1.Swirl-flow devices 3 is positioned on the hybrid channel 16 and front end of close centerbody 1, that is, between centerbody 1 and annular wall 2, for the formation of eddy flow; The end of centerbody 1 is provided with centerbody head end wall 4, and accordingly, the end of annular wall 2 is provided with annular wall end wall 7.And, be enclosed to form by the tube chamber ring wall 8 that liquidates the tube chamber 6 that liquidates between centerbody head end wall 4 and annular wall end wall 7, that is, liquidate tube chamber ring wall 8 between centerbody head end wall 4 and annular wall end wall 7.The tube chamber 6 that liquidates formed is the chamber structure of open at one end shape, and its shape is not limited to certain particular form.At the airflow hole 9 that liquidates tube chamber ring wall 8 being provided with and being communicated with hybrid channel 16 that liquidates.
During use, the fuel-air mixture ejected from opposed jets hole 9 has larger momentum, and paired opposed jets, after impacting mutually, can further improve the mixing uniformity of fuel air mixture; And, in limited physical space, also can form local return district by the circumferential zones between the region of upstream, opposed jets hole 9 and opposed jets hole 9, contribute to the stability improving flame.
As shown in Figure 2, at least offer the airflow hole 9 that liquidates for a pair liquidating on tube chamber ring wall 8, and the axial line of the airflow hole 9 that liquidates of each centering is identical, thus can opposed jets be formed.
Further, airflow hole 9 is liquidated for straight hole.Such as, and the hole shape (cross section) of the airflow hole 9 that liquidates is circular or oval or rectangle, certainly, also can select the airflow hole 9 that liquidates of other hole shapes according to actual needs: pentagon etc.
The centerbody head end wall 4 of the present embodiment is provided with centerbody head end wall spray-hole 5, and meanwhile, annular wall end wall 7 is provided with annular wall end wall spray-hole 10.Wherein, centerbody head end wall spray-hole 5 is for being communicated with centerbody inner passage and liquidating tube chamber 6, and annular wall end wall spray-hole 10 is for being communicated with the ignition zone of hybrid channel 16 and burner inner liner.Certainly, centerbody head end wall spray-hole 5 also can be multiple with the form of annular wall end wall spray-hole 10, such as: straight hole or inclined hole.Wherein, straight hole is the through hole offered vertically, and inclined hole is the through hole offered with the direction vector of radial direction vertically.In addition, also for the tangential hole for making fuel be rotated through, certainly, the hole of other types can also be can be, such as, bellmouth etc.
Further, the diameter of centerbody head end wall 4 is not less than the diameter of centerbody 1.When the diameter of centerbody head end wall 4 is greater than the diameter of centerbody 1, and the radial space exceeded is when enough offering centerbody head end wall spray-hole 5, centerbody head end wall spray-hole 5 can spray a small amount of fuel-air mixture and enter the tube chamber 6 that liquidates, and most of fuel-air mixture is then by spraying in the tube chamber 6 that liquidates at the airflow hole 9 that liquidates that tube chamber ring wall 8 is offered in pairs that liquidates.
And the axial location of this centerbody head end wall 4 is in the axial range of annular wall 2, that is, centerbody head end wall 4 is within the coated scope of annular wall 2.
In the present embodiment, swirl-flow devices 3 comprises the swirl vane 11 that centrally body 1 circumference is arranged, and swirl vane 11 is provided with teasehole 12, centerbody 1 is provided with the fuel channel 13 be communicated with teasehole 12, for hybrid channel 16 transfer the fuel.
The present invention also provides a kind of gas turbine, and it comprises fuel-air blender, and this fuel-air mixer application is in the combustion chamber of gas turbine.
Operation principle of the present invention is as follows: first, extraneous air enters the hybrid channel 16 between centerbody 1 and annular wall 2 through the air-flow that swirl-flow devices 3 forms rotational flow, fuel enters the swirl vane 11 of hollow from fuel channel 13, and spray in hybrid channel 16 from the teasehole 12 that swirl vane 11 is arranged, air and the position of fuel residing for swirl-flow devices 3 start mixing, and flow through the axial location of the centerbody head end wall 4 of centerbody 1 end until annular wall end wall 7.
Afterwards, part of fuel air Mixture is directly injected into into burner inner liner by the annular wall end wall spray-hole 10 that annular wall end wall 7 is offered, and, centerbody head end wall spray-hole 5 can spray a small amount of fuel-air mixture and enter the tube chamber 6 that liquidates, and most of fuel-air mixture is by spraying in the tube chamber 6 that liquidates at the airflow hole 9 that liquidates that tube chamber ring wall 8 is offered in pairs that liquidates, the air-flow 14 that liquidates of large momentum impacts (as shown in Figure 3) mutually, except the mixing uniformity of fuel air mixture can be improved further, also the circumferential zones between the region and opposed jets hole of upstream, opposed jets hole is formed recirculating zone 15 (as shown in Figure 3) in the chamber that liquidates locally, this will contribute to the stability improving flame.
Simultaneously, the fuel-air mixture that the annular wall end wall spray-hole 10 that annular wall end wall 7 is offered sprays can cool annular wall end wall 7, the centerbody head end wall spray-hole 5 that centerbody head end wall 4 is offered can cool centerbody head end wall 4, and the air-flow of centerbody head end wall spray-hole 5 can not have obvious destruction to ensure stable recirculation zone to neighbouring recirculating zone.
To sum up, the invention provides a kind of fuel-air blender, the fuel-air mixture ejected from opposed jets hole has larger momentum, and paired opposed jets, after impacting mutually, realizes the mixing uniformity improving fuel air mixture further; And, in limited physical space, also can form local return district by the circumferential zones between the region of upstream, opposed jets hole and opposed jets hole, thus contribute to the stability improving flame; This fuel-air mixer structure is simple, easily realizes, and not by the restriction of combustion chamber miscellaneous part, the problem such as not to mate.
Embodiments of the invention provide in order to example with for the purpose of describing, and are not exhaustively or limit the invention to disclosed form.Many modifications and variations are apparent for the ordinary skill in the art.Selecting and describing embodiment is in order to principle of the present invention and practical application are better described, and enables those of ordinary skill in the art understand the present invention thus design the various embodiments with various amendment being suitable for special-purpose.