Study on flow and heat transfer characteristics of two axial preswirl structures

IF 4.9 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Thermal Sciences Pub Date : 2024-10-10 DOI:10.1016/j.ijthermalsci.2024.109439

Zeyu Wu , Nan Cao , Jiahua Liu , Xiang Luo

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引用次数: 0

Abstract

Turbine blade cooling air is facilitated in part by the pre-swirl system, a crucial part of the aero-engine secondary air system. This article primarily focuses on the pre-swirl angle and the turbine co-rotating cavity in order to improve the pre-swirl system's temperature drop. It also employs the thermochromic liquid crystal test method to investigate the pre-swirl system's temperature drop characteristics and the cavity's cooling effect. The experimental parameters are measured at different flow rates when the rotational Reynolds number is between 2.97 × 10⁶ and 4.23 × 10⁶. The results indicate that within the experimental operating range, for the axial pre-swirl structure, the fluid velocity is fast and the static temperature is significantly reduced after pre-rotation. The higher the rotational Reynolds number, the lower the static temperature of the fluid passing through the receiving hole, and the higher the outlet temperature rise. The tangential velocity of the 15-degree preswirl structure is low, the static temperature of the receiving hole is high, and the average outlet temperature increases. In terms of pressure loss, the higher the rotational Reynolds number, the lower the fluid static pressure. The larger the pre-swirl flow rate, the higher the static pressure inside the cavity. The outlet static pressure of the 15-degree structure is higher than that of the 10-degree structure. The swirl ratio increases with an increasing flow rate. The swirl ratio decreases as the rotational Reynolds number increases. The 15-degree structure's swirl ratio is significantly lower than that of the 10-degree structure. Entropy generation is mostly produced along the trailing edge of the blade and in the vicinity of the wall, and the entropy generation of the 15-degree preswirl structure is higher than that of the 10-degree structure. On the disc's surface, the convective heat transfer coefficient rises with a rising dimensionless flow rate and falls with an increasing rotational Reynolds number.

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两种轴向预漩涡结构的流动和传热特性研究

涡轮叶片冷却空气部分由预漩涡系统提供，预漩涡系统是航空发动机二次空气系统的重要组成部分。本文主要关注预漩涡角度和涡轮共转腔，以改善预漩涡系统的温降。文章还采用热致变色液晶测试方法研究了预漩涡系统的温降特性和空腔的冷却效果。当旋转雷诺数在 2.97 × 106 和 4.23 × 106 之间时，在不同流速下测量了实验参数。结果表明，在实验操作范围内，对于轴向预漩涡结构，预旋转后流体速度很快，静态温度明显降低。旋转雷诺数越大，通过接收孔的流体静态温度越低，出口温升越高。15 度预旋流结构的切向速度低，接收孔的静态温度高，平均出口温度升高。在压力损失方面，旋转雷诺数越高，流体静压越低。预漩涡流量越大，腔内静压越高。15 度结构的出口静压高于 10 度结构。漩涡比随着流速的增加而增大。漩涡比随着旋转雷诺数的增加而减小。15 度结构的漩涡比明显低于 10 度结构。熵的产生主要沿叶片后缘和叶片壁附近产生，15 度预漩涡结构的熵产生量高于 10 度结构。在圆盘表面，对流传热系数随着无量纲流速的增加而上升，随着旋转雷诺数的增加而下降。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

International Journal of Thermal Sciences 工程技术-工程：机械

CiteScore

8.10

自引率

11.10%

发文量

531

审稿时长

55 days

期刊介绍： The International Journal of Thermal Sciences is a journal devoted to the publication of fundamental studies on the physics of transfer processes in general, with an emphasis on thermal aspects and also applied research on various processes, energy systems and the environment. Articles are published in English and French, and are subject to peer review. The fundamental subjects considered within the scope of the journal are: * Heat and relevant mass transfer at all scales (nano, micro and macro) and in all types of material (heterogeneous, composites, biological,...) and fluid flow * Forced, natural or mixed convection in reactive or non-reactive media * Single or multi–phase fluid flow with or without phase change * Near–and far–field radiative heat transfer * Combined modes of heat transfer in complex systems (for example, plasmas, biological, geological,...) * Multiscale modelling The applied research topics include: * Heat exchangers, heat pipes, cooling processes * Transport phenomena taking place in industrial processes (chemical, food and agricultural, metallurgical, space and aeronautical, automobile industries) * Nano–and micro–technology for energy, space, biosystems and devices * Heat transport analysis in advanced systems * Impact of energy–related processes on environment, and emerging energy systems The study of thermophysical properties of materials and fluids, thermal measurement techniques, inverse methods, and the developments of experimental methods are within the scope of the International Journal of Thermal Sciences which also covers the modelling, and numerical methods applied to thermal transfer.