Study on Heat Transfer Characteristics of Brush-Type Sealing Labyrinth

Peiqi Zhou; Xin Li; Heshun Wang; Weibing Zhu

doi:10.6911/WSRJ.202602_12(2).0010

Authors

Peiqi Zhou
Xin Li
Heshun Wang
Weibing Zhu

DOI:

https://doi.org/10.6911/WSRJ.202602_12(2).0010

Keywords:

Brush sealing, Labyrinth sealing, Interlocking teeth, Heat transfer characteristics

Abstract

This study addresses the significant deviation between actual heat consumption rates and design values caused by inter-stage air leakage in a power plant steam turbine's staggered-tooth labyrinth seal system. Focusing on retrofitting existing labyrinth seals, we implemented brush seals at specific stator sealing tooth positions based on field operational data. The proposed hybrid system demonstrates that maximum temperature serves as the primary thermal performance metric for evaluating structural and operational parameters. Key findings include: 1) Positive correlations exist between brush wire diameter, bundle thickness, brush ring inner diameter, temperature, and rotational speed with maximum temperature, while negative correlations are observed for brush arrangement angle, front/rear plate height, brush ring outer diameter, sealing clearance, and pressure differential. Labyrinth tooth clearance has minimal impact. 2) Temperature variations primarily result from frictional heat generation and leakage variations caused by parameter adjustments.

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