Automotive Water & Liquid Simulation

11 March 2021
Germany, Virtual
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Egon Wiedekind
marketing.germany [at]


Ensuring performance, comfort and safety under harsh weather conditions and extreme driving situations is crucial for customer satisfaction and passenger safety. ADAS systems are increasingly equipped with more and more sensors. These must be kept clear and free from rain drops, snow and dirt in order to perform optimally. The same applies to the driver's field of vision. Sensitive technical components must be protected against the ingress of water. But complex fluids are also used in vehicles in the form of fuel, coolant or lubricant. Classical test methods often reach their limits. Here, increasingly performant simulation methods can provide significant advantages in predicting the behavior of fluids. Different methods and software tools are available for this purpose.


ESI is attending this event an presenting the following topic: Virtual Car Prototyping in Realistic Driving Environment by Dr. Matthias Schäfer


To develop future electrical and autonomous cars, it is important to virtually test the car in real driving circumstances, including on wet road or under heavy rain conditions. It is especially critical to check that no water prevents the sensors of the driving assistance systems or autonomous cars from working properly, that water intrusion does not disturb electrical equipment, and that the driver’s visibility remains good under rain condition.

To simulate the interaction of the water with the car structure, ESI Group combined the mesh free Finite Point Method (FPM) with their structural dynamics solver Virtual Performance Solution (VPS). Initially this solution was specialized for tank sloshing and water drain applications for car closures. Now it was extended for cases dealing with full car water crossing including deformable tires and suspensions and soiling scenarios.

The objective is to enable a holistic prediction of the car behavior under realistic driving conditions, using a virtual car prototype. Detailed water behavior is accounted for, along with the deformation of structural part. Targeted scenarios include the specific problematics of electrical cars, related to water intrusion on wet road or heavy rain. Special care also should be taken during water crossing scenarios for the prediction of drivability and that the water does not prevent autonomous car sensors of working as expected. The ability to simulate rain can improve safety and driving comfort by ensuring good visibility through windows and towards side mirrors. Finally, prediction of water forces acting on structural parts is essential to prevent accidental failures due to water splash and brutal thermal effects.

Dr. Matthias Schäfer

Solution Management Team Leader, ESI

About Virtual Performance Solution

  • Shift towards zero real tests, significantly reducing or eliminating costly real tests altogether 
  • Virtually assess complex new tests for new vehicles [water crossing, airbags, regulatory crash tests (including battery), vibro-acoustics tests], all while using a combination of lightweight materials
  • Ensure high predictivity with access to multi-scale modeling using detailed modeling where needed, and the chaining of manufacturing effects – this seems out of place to me 
  • The Single Core Model makes it possible to investigate designs options and variations and make the best trade-offs, reducing time spent on the synchronization of models between domains
  • High-performance computing and multi-scale modeling delivers accuracy, only where needed, for a shorter calculation time
  • Expert modeling support helps you explore new virtual test and integrate them into your engineering process workflow

Learn more about VPS.