all these raindrops falling down my window

#All these raindrops falling down my window license#

The conditions needed to dislodge the drop We assume that the car is driven with a constant speed on a straight line (so that it can be considered as an inertial frame of reference) and that we have access to the local wind on the car window (value and direction). Hypothesis: we consider a single drop holding on a car side window. The wetting of the window makes it easier to take some predefined paths (canals), as we can see on the top part on the window. Merging between drops occur, which makes the different paths quite erratic. The drops have different trajectories some of them are going up, other have almost horizontal directions. Picture of rain drops on the side window of a moving car. We finally discuss how our model could be used as a basis to study a whole population of drops on a car window, where the geometry of the car, surface treatment and drop merging play crucial roles. Experimental results are then provided and enable us to validate the models and explain the different regimes observed on a car window. We first present our method to model the dynamics of a drop undergoing gravity, drag forces and capillarity forces (due to the interaction of the drop with the surface). In this paper, we will focus on the trajectories of rain drops once they are on the side windows, where all the forces mentioned above must be taken into account. However, none of those studies have tackled the determination of the drops' trajectories. The subject concerning drops on a car side window has been studied in, where emphasis was put on removing drops from the glass to enhance visibility. The specific problem of a car window also involves aerodynamic effects such as side vortices, which have been meticulously studied in. A thorough study of the parameters involved in the drag force can be found in. The dynamic of drops on a plane surface has been investigated usually in simpler conditions: the influence of gravity and drag force has been separately looked at. This subject has already been closely studied and will not be consider in this paper. Another subject, important for visibility issues and quite close to the dynamic of drops on a car window, is the formation and stability of thin films and rivulets, such as the localized canals observed in Figure 1. This subject is therefore greatly interesting the automobile field. The motion of rain drops on a car is of tremendous interest, since if they stick on the glass they limit the visibility through the window, which may trigger safety issues. The purpose of this study is to identify those different regimes of behaviors and to explain the observed trajectories. You will have probably already noticed a puzzling phenomenon while driving your car in the rain: on the side-windows of a moving car, rain drops may adopt a wide range of behaviors and trajectories, as shown in Figure 1, some of them stay at rest, while others tend to move either downwards or upwards.

#All these raindrops falling down my window license#

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