Optimizing Race Car Fuel Tank Design: A Meshless CFD Approach

Modern racing demands constant innovation in every component, including fuel tank design. A recent breakthrough study by Dallara Automobili demonstrates how meshless Computational Fluid Dynamics (CFD) can revolutionize fuel tank optimization in high-performance racing vehicles.

Racing cars face several engineering challenges related to fuel systems:

1. Minimizing Center of Gravity (COG)
   • Higher COG increases lateral load transfer during cornering
   • Greater lateral loads reduce tire grip
   • Excessive body roll diminishes crucial downforce
   • Fuel mass significantly impacts overall vehicle dynamics
2. Fuel Delivery Reliability
   • Racing cars experience acceleration forces exceeding 2g
   • Feed pumps must maintain consistent fuel flow to high-pressure pumps
   • Fuel sloshing can interrupt proper engine operation
   • Power loss occurs when pumps can't maintain adequate flow

Comparison with other simulation methods and numerics

Dallara implemented Moving Particle Simulation (MPS), a meshless CFD method, achieving remarkable improvements over traditional Finite Volume Method (FVM) CFD:

• Traditional FVM CFD: Required 8-node cluster with 512 cores
• MPS Approach: Single Nvidia A40 processor
• Time Savings: Successfully simulated 400 seconds of physical time in 24 hours (compared to 36 seconds with FVM)

As particle size increased from baseline 2.5mm to 4.0mm, the maximum error grew from 0.9% to 2.1%. 3.5mm particle size provided the best balance between accuracy and computational efficiency. Negligible impact on x and y COG coordinates.

Innovative Solution: PTFE Sphere Implementation

A groundbreaking aspect of the study involved introducing Teflon spheres into partially filled tanks. This solution is particularly relevant for: Formula 1/Formula 2: When fuel load is below maximum capacity and during Balance of Performance (BOP) adjustments.

The addition of PTFE spheres resulted in significant sloshing reduction, altought simulation time increased due to complex particle interactions. On fuel extraction, no negative impact on pump flow rates was found. Importantly, the addition of PTFE spheres helped lower the baricenter (Z-COG) by 17%.

Engineering Implications

This study demonstrates several key advantages for racing teams:

1. Design Optimization Faster iteration cycles for tank designs and comprehensive track analysis capability
2. Performance Benefits Improved vehicle stability through better COG management and improved fuel delivery reliability
3. Computation Efficiency Reduced computational resource requirements and aster turnaround time for design iterations

If you are interested in deepening the topic, read this article.