Modeling of Droplet Deformation Near the Leading Edge of an Airfoil

Suthyvann Sor; Adelaida García-Magariño

doi:10.2514/1.c033086

Improved Taylor analogy breakup and Clark models for droplet deformation prediction

Proceedings of the Institution of Mechanical Engineers Part G Journal of Aerospace Engineering ◽

10.1177/0954410017736545 ◽

2017 ◽

Vol 233 (2) ◽

pp. 767-775 ◽

Cited By ~ 2

Author(s):

Zhenlong Wu ◽

Benyin Lv ◽

Yihua Cao

Keyword(s):

Leading Edge ◽

Surface Tension Force ◽

Aerodynamic Characteristics ◽

Viscous Force ◽

Pressure Force ◽

Droplet Deformation ◽

Deformation Prediction ◽

Clark Model ◽

Improved Model ◽

Breakup Model

The deformation of rain droplet at the leading edge of a wing is critical to the aerodynamic characteristics of the aircraft under heavy rainfall and icing conditions. This study introduces the improvement of the Taylor analogy breakup and Clark models for prediction of droplet deformation near the leading edge of an airfoil. The slip velocity is considered as time-variant in the improved Taylor analogy breakup model. The viscous force is optimized in the improved Clark model. The prediction results suggest that the Clark models predict better results than the Taylor analogy breakup models. Besides, the improved Clark model has the highest prediction accuracy. However, considering the Clark model is derived based on a two-dimensional model, even the improved model still has some unavoidable deviations from the real situation. In addition, the simplified surface area in the surface tension force and the approximation of the pressure force in the original Clark model are very effective, thus are kept the same in the improved Clark model.

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Rotating Arm-Based Experimental Study on Droplet Behavior in the Shoulder Region of an Aircraft Aerodynamic Surface

International Journal of Aerospace Engineering ◽

10.1155/2017/8390905 ◽

2017 ◽

Vol 2017 ◽

pp. 1-12 ◽

Cited By ~ 3

Author(s):

S. Sor ◽

A. García-Magariño ◽

A. Velazquez

Keyword(s):

Experimental Study ◽

Imaging System ◽

Leading Edge ◽

Base Flow ◽

Particle Image Velocimetry System ◽

Edge Region ◽

Droplet Deformation ◽

Droplet Behavior ◽

Shoulder Region ◽

Set Up

An experimental study has been performed on water droplet deformation in the shoulder region of an airfoil. The experiments have been carried out in a rotating arm facility 2.2 m long and able to rotate up to 400 rpm (90 m/s). A blunt airfoil model (chord length equal to 0.468 m) was placed at the end of the arm. A droplet generator was used to generate a stream of water droplets with an initial diameter of 1000 μm. An imaging system was set up to record the trajectories and deformations of the droplets in three different regions close to the airfoil shoulder. The base flow field was characterized using a particle image velocimetry system. The experiments show that droplet deformation results in the shoulder region of the airfoil are different from those pertaining to the leading edge region. In particular, droplets in the shoulder region tend to rotate to the direction of the incoming airfoil which generates an interference effect between the droplets that make up the stream. These differences have been quantified applying an existing theoretical model specifically developed for the leading edge region to the results obtained in the present study.

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An experimental study of water droplets deformation and collision with airfoil

International Journal of Modern Physics B ◽

10.1142/s0217979220400949 ◽

2020 ◽

Vol 34 (14n16) ◽

pp. 2040094

Author(s):

Wen Li ◽

Bo Miao ◽

Chun-Ling Zhu ◽

Ning Zhao

Keyword(s):

Experimental Study ◽

Weber Number ◽

High Speed ◽

Leading Edge ◽

Deformation Mode ◽

Water Droplets ◽

Droplet Deformation ◽

Naca0012 Airfoil ◽

Droplet Movement ◽

Pass Through

When aircraft pass through the clouds that contain super cooled water droplets during aviation, the droplets collide with the wing surface and ice is formed, which induces a significant threat to aviation safety. Studies on droplet movement in gaseous medium are prerequisite for deicing/anti-icing researches. So, in this work, an experimental study is performed on water droplet deformation as the droplets approach the leading edge of an airfoil. This experiment is carried out in a vertical wind tunnel, with a NACA0012 airfoil model assembled 4.3 m downstream of the droplet generator. The influence of Weber number (ranging from 0.2 to 36) on the deformation of a 2 mm diameter droplet is thoroughly investigated. The results indicate that droplets maintain initial form with Weber number under 10; after that droplet deforms into remarkable bag deformation as Weber number reaches to 19, and bag-stamen deformation mode as Weber number is above 20. This observed correlation between Weber number and deformation mode is validated through comparing with published simulation results. Furthermore, using the high-speed camera, clear images of the droplet structure during the deformation process are taken and are shown in detail in this work.

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