The present disclosure relates to a duct and, more particularly, to a rectilinear duct with stress relief.
Gas turbine engines, such as those which power modern military aircraft, include a compressor section to pressurize a supply of air, a combustor section to burn a hydrocarbon fuel in the presence of the pressurized air, and a turbine section to extract energy from the resultant combustion gases and generate thrust. An augmentor section, or “afterburner”, may be located downstream of the turbine section to selectively increase thrust.
In some buried engine arrangements, an exhaust duct downstream of the augmentor may be at least partially rectilinear in cross-section A rectangular shaped duct exposed to hot gases may result in relatively high corner stresses.
A duct liner according to one disclosed non-limiting embodiment of the present disclosure includes a corner flanked by a pair of keyhole slots.
A further embodiment of the present disclosure includes, wherein each of the pair of keyhole slots are displaced from the corner.
A further embodiment of any of the foregoing embodiments of the present disclosure includes, wherein each of the pair of keyhole slots extend parallel to the corner.
A further embodiment of any of the foregoing embodiments of the present disclosure includes, wherein each of the pair of keyhole slots extend through a flange
A further embodiment of any of the foregoing embodiments of the present disclosure includes, wherein each of the pair of keyhole slots are linear.
A further embodiment of any of the foregoing embodiments of the present disclosure includes, wherein each of the pair of keyhole slots includes a circular end.
An exhaust duct assembly according to another disclosed non-limiting embodiment of the present disclosure includes an impingement liner received within the duct; and a duct liner received within the impingement liner, the duct liner with a multiple of corners, each of the corners flanked by a pair of keyhole slots.
A further embodiment of any of the foregoing embodiments of the present disclosure includes, wherein each of the pair of keyhole slots are displaced from the corner.
A further embodiment of any of the foregoing embodiments of the present disclosure includes, wherein each of the pair of keyhole slots extend parallel to the corner.
A further embodiment of any of the foregoing embodiments of the present disclosure includes, wherein each of the pair of keyhole slots extend through a duct liner flange of the duct liner.
A further embodiment of any of the foregoing embodiments of the present disclosure includes, wherein the duct liner flange abuts an impingement liner flange of the impingement liner.
A further embodiment of any of the foregoing embodiments of the present disclosure includes a gasket between the duct liner flange and the impingement liner flange.
A further embodiment of any of the foregoing embodiments of the present disclosure includes, wherein the duct liner flange abuts a bulkhead.
A further embodiment of any of the foregoing embodiments of the present disclosure includes, wherein the bulkhead is defined by a gas turbine engine.
A further embodiment of any of the foregoing embodiments of the present disclosure includes, wherein the bulkhead is defined by a Hot Acoustic Rig.
A further embodiment of any of the foregoing embodiments of the present disclosure includes, wherein each of said pair of keyhole slots includes a circular end.
A further embodiment of any of the foregoing embodiments of the present disclosure includes, wherein said circular end is displaced from each corner by 2.5 times a diameter of said circular end.
The foregoing features and elements may be combined in various combinations without exclusivity, unless expressly indicated otherwise. These features and elements as well as the operation of the invention will become more apparent in light of the following description and the accompanying drawings. It should be understood, however, the following description and drawings are intended to be exemplary in nature and non-limiting.
Various features will become apparent to those skilled in the art from the following detailed description of the disclosed non-limiting embodiment. The drawings that accompany the detailed description can be briefly described as follows:
The exhaust duct section 32 may be generally rectilinear in cross-section (also shown in
With reference to
With reference to
The pairs of keyhole slots 86 minimize the accumulation of thermal strain through controlled deformation as the duct liner flange 80 cannot otherwise carry a bending load at the corners 84. That is, the pairs of keyhole slots 86 which flank each corner 84 permit controlled moment to minimize the accumulation of thermal strain.
It should be understood that like reference numerals identify corresponding or similar elements throughout the several drawings. It should also be understood that although a particular component arrangement is disclosed in the illustrated embodiment, other arrangements will benefit herefrom.
Although the different non-limiting embodiments have specific illustrated components, the embodiments of this invention are not limited to those particular combinations.
It is possible to use some of the components or features from any of the non-limiting embodiments in combination with features or components from any of the other non-limiting embodiments.
Although particular step sequences are shown, described, and claimed, it should be understood that steps may be performed in any order, separated or combined unless otherwise indicated and will still benefit from the present disclosure.
The foregoing description is exemplary rather than defined by the limitations within. Various non-limiting embodiments are disclosed herein, however, one of ordinary skill in the art would recognize that various modifications and variations in light of the above teachings will fall within the scope of the appended claims. It is therefore to be understood that within the scope of the appended claims, the disclosure may be practiced other than as specifically described. For that reason the appended claims should be studied to determine true scope and content.
This application claims priority to U.S. Patent Appln. No. 61/765,208 filed Feb. 15, 2013.
Number | Date | Country | |
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61765208 | Feb 2013 | US |