THERMAL SCIENCE

International Scientific Journal

Thermal Science - Online First

Yan Pin

,

Xiaoyuan Wen

,

Xiaodan Hu

,

Shuo Cheng

,

Shuna Qi

,

Zhuhai Zhong

,

Pengfei Han

,

Cun Wang

,

Wei Jiang

online first only

Investigation of enhanced heat transfer in hollow blade by diamond-inspired structure for dehumidification in steam turbine

ABSTRACT
Wet steam erosion plays a pivotal role in influencing the efficient and safe operation of steam turbines. The dehumidification technique, which combines hollow blade heating and purging, exhibits significant performance in the low-pressure, long-blade stages. However, the hollow structure has a pronounced impact on blade strength and often results in low heat transfer efficiency. In this study, we introduce a turbulence generator inspired by the diamond lattice bonding to modify the internal channel structure of hollow long blades. This diamond-inspired structure aims to enhance turbulence within the blades, thereby increasing surface area and heat transfer coefficients, ultimately reducing erosion caused by secondary water droplets on downstream blades. Our findings indicate that incorporating a diamond-inspired structure as a framework within the conventional slot cavity blades results in a notable temperature increase on the blade surfaces. Specifically, at 100% rated flow conditions, the average blade surface temperature rises from 352K to 357K. The diamond-inspired structure enhances heat transfer without significantly compromising the blades' power output. Furthermore, reducing the bond length from 30mm to 20mm leads to an additional temperature increase from 357K to 359K. This suggests that a denser diamond lattice structure is more favorable for heating the stator blades.
KEYWORDS
heat transfer, dehumidification, steam turbine, Diamond-inspired Structure
PAPER SUBMITTED: 2024-08-12
PAPER REVISED: 2024-11-05
PAPER ACCEPTED: 2024-11-06
PUBLISHED ONLINE: 2024-12-07
DOI REFERENCE: https://doi.org/10.2298/TSCI240812265P
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Investigation of enhanced heat transfer in hollow blade by diamond-inspired structure for dehumidification in steam turbine