Numerical simulation of wetting on vehicle's windshields
Typ
Examensarbete för masterexamen
Program
Publicerad
2022
Författare
Karimi, Armita
Modellbyggare
Tidskriftstitel
ISSN
Volymtitel
Utgivare
Sammanfattning
In this project, the spreading dynamics of a single droplet over surfaces with different
wettability conditions are studied by means of a series of numerical simulations
aiming to model the motion of a rain droplet over vehicles’ windshields. To do so,
a Cahn-Hilliard formulation of the Phase Field (PF) is employed.
The wettability of the surface is modelled by imposing a contact angle. During the
spreading process, the three-phase contact line moves over the surface while the prescribed
contact angle is fulfilled. to successfully remove the well-known contact line
singularity problem, a dynamic contact angle together with a slip velocity boundary
conditions are imposed at the surface.
Given the variety of parameters governing the dynamics of the problem, including
properties of each phase (viscosity, density, etc.) the angle of the windshields, surface
wettability, relative wind velocity, thermo-physical properties (such as ambient
temperature ,cabin temperature) and considering computational costs, the focus of
this study is on the effects of windshields’ angle, relative wind velocity and surface
wettability. To further investigate the problem, several additional simulations have
been performed for selected cases to scrutinize the effects of fluid properties.
Beskrivning
Ämne/nyckelord
phase field method (PFM) , contact line dynamic , interface , diffuse interface (DI) methods