Development of a Mathematical Model for the Flow of the Working Fluid in the Gaps of a Brush Seal and Adjacent Cavities of Bypass Turbojet Engines
Authors: Zagorodnikov S.A., Siluyanova M.V., Trunova E.A.
Published in issue: #6(174)/2026
Category: Aviation and Rocket-Space Engineering | Chapter: Thermal, Electric Jet Engines, and Power Plants of Aircrafts
Leaks of the working fluid through the gaps between the movable and fixed elements of gas turbine engines reduce their efficiency by 0.5–1.5%. Brush seals provide higher airtightness compared to traditional labyrinth structures. However, the design of such seals is complicated by the complex nature of the flow through the porous structure of the package and the influence of adjacent cavities on the distribution of flow parameters. The paper presents a mathematical model of the air flow in the gaps of a brush seal and adjacent cavities of a turbojet two-circuit engine. The model is based on the representation of a package of bristles as an anisotropic porous medium. The numerical implementation is performed by the finite volume method using the k-ε turbulence model. A parametric analysis of the effect of the radial gap, the thickness of the package, the packing density of the bristles and their angle of inclination on the leakage rate is carried out. It was found that reducing the gap from 0.10 to 0.05 mm reduces consumption by 34.6%, and increasing the packing density from 500 to 800 pcs/mm2 by 42.0%. Pressure and velocity distributions along the seal are constructed, and zones of maximum gradients are identified. It has been shown that brush seals provide a 30–40% reduction in leakage compared to three-prong labyrinth analogues. The results are applicable in the design of sealing assemblies of aircraft engines.
EDN WUIYVO
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