Unleashing Efficiency: Large Eddy Simulations Revolutionizing Vehicle Design

In the dynamic landscape of automotive design, optimizing aerodynamics is key to achieving peak performance, fuel efficiency, vehicle range, and sustainability. Large eddy simulation (LES), a cutting-edge simulation technique, is reshaping how we approach automotive aerodynamics design.

Understanding LES

At its core, LES focuses on energy-containing larger turbulent structures, and a subgrid-scale model is used for smaller structures. This approach surpasses Reynolds-averaged Navier–Stokes (RANS) simulations, offering a deeper understanding of the complexities influencing a vehicle's aerodynamics and acoustic performance.

Decoding Turbulence Complexities

Turbulence within the automotive aerodynamic environment is inherently complex, with various factors influencing the flow around the vehicle. LES excels in unraveling these complexities by providing a detailed representation of turbulent structures. This heightened precision allows engineers to analyze the impact of small-scale vortices and eddies on drag, lift, and overall aerodynamic efficiency, as well as aeroacoustics to characterize external noise sources.

Precision in Design

One of the primary advantages of LES lies in its ability to offer more accurate predictions of aerodynamic forces and moments. By capturing finer details of the flow field and accurately quantifying the impact on performance between design changes, engineers can make informed design decisions based on more precise simulation data. This increased accuracy reduces reliance on physical prototypes, saving valuable time and resources.

Addressing Real-World Conditions

Automotive aerodynamics do not occur in controlled, idealized environments. It is important to simulate real-world conditions, considering factors such as rotating wheels, ground effects, crosswinds, and complex geometries. LES simulations offer a higher degree of precision in capturing such effects, many of which involve unsteady flow behavior. This realism is crucial for developing vehicles that perform optimally in diverse and unpredictable conditions, enhancing overall safety and stability.

Computational Intensity

While LES offers superior accuracy, it comes at a higher computational cost compared to RANS. The detailed simulation of turbulent structures demands more computational resources, impacting feasibility for specific applications.

Breaking Down the Wall: WMLES

Traditionally, LES near solid boundaries required very refined grid resolutions to capture near-wall turbulence accurately, incurring high computational costs. Wall-Modeled Large Eddy Simulation (WMLES) introduces a wall model to capture near-wall turbulence, allowing for coarser grids and increased computational efficiency. Striking a balance between accuracy and efficiency, this innovation enables engineers to achieve high-fidelity simulations with reduced computational demands, making it a practical choice for complex automotive aerodynamics and aeroacoustics studies.

Fidelity CFD Accelerates LES

Cadence Fidelity LES solver addresses LES challenges by maximizing simulation throughput without sacrificing accuracy. Leveraging GPU acceleration reduces computational costs, making it more accessible for engineering design applications. Engineers can achieve full-vehicle LES in a matter of hours. Interactive exploration and detailed post-processing capabilities enable them to easily navigate and analyze intricate details of the 3D flow field and extract valuable insights.

To learn more about Fidelity CFD for automotive aerodynamics large eddy simulation, watch our on-demand webinar:

In conclusion, Large Eddy Simulation is a game-changer in the field of automotive aerodynamics and aeroacoustics design and development. Its ability to dissect turbulent flows, enhance accuracy, address real-world conditions, and drive innovation positions it as a cornerstone in the pursuit of next-generation vehicles. As we harness the power of LES, we move towards a future where automotive design seamlessly blends precision, efficiency, and sustainability.