An ultra-compact and high-efficiency racemic lobe mixing exhaust system structure

Abstract

The invention relates to the technical field of mixed air exhaust systems, in particular to an ultra-compact and high-mixing-efficiency air exhaust system structure adopting a de-swirl lobe mixer. The ultra-compact and high-mixing-efficiency air exhaust system structure adopting the de-swirl lobe mixer is especially suitable for a high-performance aviation gas turbine fan engine. The ultra-compact and high-mixing-efficiency air exhaust system structure adopting the de-swirl lobe mixer comprises the de-swirl lobe mixer with an inlet flow angle, a central cone with a bump and a mixing spray tube; a plurality of wing type reinforcing rib connecting structures are arranged between the de-swirl lobe mixer and the central cone; the lower ends of wing type reinforcing ribs are fixedly connected to the central cone with the bump; the upper ends of the wing type reinforcing ribs are fixedly connected to a de-swirl lobe trough; a trough lobe is a specially-shaped blade structure; the specially-shaped blade has an inlet flow angle; the side wall of the lobe mixer is subjected to concave sector cutting processing; and distances between the front edges of the lower ends of the reinforcing ribs to bump slope of the central cone are 0-3 times chord length of the reinforcing ribs. The ultra-compact and high-mixing-efficiency air exhaust system structure adopting the de-swirl lobe mixer has a plurality of advantages of being high in mixing efficiency, strong in pre-whirling resistance, compact in structure, high in reliability, low in processing and maintaining cost, and the like.

Description

technical field [0001] The invention relates to the technical field of mixed exhaust systems, in particular to an ultra-compact and high-mixing-efficiency racemic lobe mixed exhaust system structure, which is especially suitable for high-performance aviation gas turbofan engines. Background technique [0002] An important characteristic difference of various types of small and medium bypass ratio aviation gas turbofan engines is the difference in the type of exhaust system components, which is different from the large bypass ratio aeroengine, which adopts the separate exhaust structure of internal and external bypass jets without pre-mixing Compared with the aero-engine exhaust system, the small and medium ducts use the mixed exhaust system in which the internal and external jets are pre-mixed in the tail nozzle. [0003] Annular mixed exhaust system is the first mixed exhaust type used, such as F100-PW-129 adopts simple annular mixed exhaust type, the advantages of this mix...

AI Technical Summary

Problems solved by technology

However, the lobe mixer also inevitably has some disadvantages mentioned above. It has a certain anti-pre-swirl ability, but the tolerance to the upstream pre-swirl is very limited, and the outlet airflow angle of the low-pressure turbine exceeding 10° will be As a result, flow separation occurs on the surface of the lobe, and a recirculation zone appears downstream of the central cone, which greatly increases the total pressure loss and thrust loss, which in turn increases the difficulty of matching the lobe mixer with the low-pressure turbine, especially with the high-load low-pressure turbine. match

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