Engine Coolant Jacket Filling and Deaeration (ABP)

Engine coolant jacket with forced circulation of coolant around the engine block, cylinder head, through the EGR and other critical components, ensures effective heat removal and avoids local hot spots during the engine operation. As the coolant jacket flow passages are a labyrinth of complex shapes, the coolant filling is prone to formation of air pockets. Therefore, it is necessary to ensure proper deaeration through provision of vent locations on the jacket, thereby avoiding any local air pockets which could potentially result in local hot spots and failure. Coolant filling simulations help designers to ensure an effective vent design while adhering to engine packaging constraints and meeting SAE norms set for coolant filling, deaeration and drain cycles. 

In this Application Best Practice (ABP), a multiphase VOF-based simulation is performed on a coolant jacket with representative coolant filling rates, coolant settling (deaeration) and top-up cycle.

Learning Outcomes:

Following completion of this course, you will be able to:

• Configure a transient multiphase (VOF) simulation in Ansys Fluent® fluid simulation software to model air–coolant interaction during filling and pump operation. 
• Apply appropriate meshing strategies, solver controls, and stabilization methods for robust coolant filling simulations. 
• Implement coolant pump behavior using internal fan boundary conditions and time‑dependent expressions. 
• Evaluate simulation results to identify air entrapment, assess deaeration effectiveness, and support venting design decisions. 

Prerequisites:

• Previous experience using and applying the Ansys Fluent CFD solver is recommended.
• Ansys Fluent Meshing with Watertight Geometry Workflow.
• Get Started with Ansys Fluent.
• Get Started with Ansys Fluent Multiphase Flow Modeling

Please note: These training materials were developed and tested in the 2025R2 release.