Purpose

The sandy environment is one of the typical environments in which helicopters operate. Air-sand two-phase flow in sandy environments may be an important factor affecting flight safety. Taking a typical example, this paper aims to investigate the aerodynamic and rotor trim characteristics of the UH-60 helicopter in sandy environments.

Design/methodology/approach

A computational study is conducted to simulate the air-sand flow over airfoils based on the Euler–Lagrange framework. The simulation uses the S-A turbulence model and the two-way momentum coupling methodology. Additionally, the trim characteristics of the UH-60 rotor are calculated based on the isolated rotor trim algorithm.

Findings

The simulation results show that air-sand flow significantly affects the aerodynamic characteristics of the SC1095 airfoil and the SC1094R8 airfoil. The presence of sand particles leads to a decrease in lift and an increase in drag. The calculation results of the UH-60 helicopter rotor indicate that the thrust decreases and the torque increases in the sandy environment. To maintain a steady forward flight in sandy environments, it is necessary to increase the collective pitch and the longitudinal cyclic pitch.

Originality/value

In this paper, the aerodynamic characteristics of airfoils and the trim characteristics in the air-sand flow of the UH-60 helicopter are discussed, which might be a new view to analyse the impact of sandy environments on helicopter safety and manoeuvring.

中文翻译：

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沙地环境下直升机翼型气动特性及旋翼配平

目的

沙地环境是直升机运行的典型环境之一。沙质环境中的气沙两相流可能是影响飞行安全的重要因素。本文以典型实例为基础，研究UH-60直升机在沙地环境下的气动和旋翼配平特性。

设计/方法论/途径

基于欧拉-拉格朗日框架进行计算研究来模拟翼型上的空气-沙流。模拟采用 SA 湍流模型和双向动量耦合方法。此外，UH-60 转子的配平特性是根据孤立转子配平算法计算的。

发现

仿真结果表明，气砂流动显着影响SC1095翼型和SC1094R8翼型的气动特性。沙粒的存在会导致升力降低和阻力增加。UH-60直升机旋翼的计算结果表明，在沙地环境下，推力减小，扭矩增大。为了在沙地环境中保持稳定的向前飞行，需要增加集体螺距和纵向循环螺距。

原创性/价值

本文讨论了UH-60直升机翼型的气动特性和风沙流中的配平特性，为分析沙地环境对直升机安全和操纵的影响提供了新的视角。