Driving a vehicle in deep water can be dangerous and may damage the vehicle. Electronics, air intake and other areas may be sensitive to water. With simulations of various configurations of water depth and car speed, as well as vehicle CAD alternatives, manufacturers can precisely set maximum wading depth and reduce the vehicle’s vulnerability to water.

High-speed wading of shallow water generates high-pressure splashes that may impact the underneath structure of the vehicle. For example, safety covers located under the vehicle protect the engine and other critical parts from impacts and stress. Their resistance is assessed by manufacturers using experimental testing of prototypes. By bringing forward these critical tests to an earlier stage of the design process, the use of CFD simulation can prevent costly design issues.

SPH-flow is applied here to simulate a 10 cm water depth fording at 40 km/h car speed. Car motion and wheel rotation are taken into account during each step of the simulation: ford entry/exit and constant level. Local Adaptive Particle Refinement (APR) method is used and applied to the vehicle. Sensors are set in order to measure the force applied by the water splashes on underbody parts.

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