CharLES

CharLES

Cadence Fidelity LES Solver (formerly Cascade CharLES)

is the industry’s first high-fidelity computational fluid dynamics (CFD) analysis engine that expands the applicability of large eddy simulations (LES) into the mainstream aerospace, automotive, and turbomachinery domains. Designed to scale, Fidelity LES Solver addresses the most demanding fluid dynamics challenges by accurately predicting traditionally complex problems for CFD in aeroacoustics, aerodynamics, combustion, heat transfer, as well as multiphase applications.

Sandia Flame D. Comparison between experiments and Fidelity LES Solver for different mesh sizes. Temperature contours (above) and centerline mean and rms temperature (below)

Figure 2: Sandia Flame D. Comparison between experiments and Fidelity LES Solver for different mesh sizes. Temperature contours (above) and centerline mean and rms temperature (below).

Aerodynamics

Fidelity LES Solver can predict aerodynamic forces for complex geometries over a range of flow regimes from low-Mach to transonic and supersonic.

For example, it can capture changes in vehicle drag due to subtle geometric design modifications (Figure 3) and identify the onset of stall over high angle of attack airfoils on a commercial aircraft.

High-fidelity CFD simulation of a commercial aircraft targeting predictions of maximum lift and stall characteristics and separation patterns (left) and the external aerodynamics of a car (right) with Fidelity LES Solver

Figure 3: High-fidelity CFD simulation of a commercial aircraft targeting predictions of maximum lift and stall characteristics and separation patterns (left) and the external aerodynamics of a car (right) with Fidelity LES Solver

Aeroacoustics

Aeroacoustics predictions are relevant for a wide range of industrial applications, from supersonic jets to fan noise to combustion-acoustic interactions in gas turbines (Figure 4).

Aeroacoustics of an eVTOL air vehicle, the pressure field, and shear stress at cruise conditions

Figure 4: Aeroacoustics of an eVTOL air vehicle, the pressure field, and shear stress at cruise conditions

Image copyright Honda Motor Co (ref AIAA 2023-3938(opens in a new tab))

Even for “extremely loud” noises, the pressure fluctuations that constitute the radiated sound are orders of magnitude smaller than the ambient pressure and much smaller than the near-field pressure disturbances associated with turbulent compressible flow. Fidelity LES Solver is ideally suited to capture such important but low-energetic acoustic features, thanks to its unsteady simulation capabilities with low-dissipation and low-dispersion numerical methods.

Read more