  In the automotive industry, multi-element wings have been used to improve the
aerodynamics of race cars. Multi-element wings can enhance a vehicle's handling
and stability by reducing drag and increasing downforce, allowing it to corner
more effectively and achieve higher speeds. Performance gains by utilizing the
ground effect are highly sensitive to the wing setup. This study focuses on
identifying the optimum design parameters for the airfoil to achieve the
desired downforce and drag performance. The design parameters chosen are ride
height, flap overlap, flap angle, and flap gap (the spacing between the flap
and the main airfoil). These parameters are optimized for three different use
cases: high downforce, low drag, and a setup with the highest airfoil
efficiency. The force coefficient and flow field data were gathered using
two-dimensional (2D) Reynolds Averaged Navier Stokes (RANS) simulations, with
the turbulent flow modeled using the k-{\omega} Shear Stress Transport (SST)
turbulence model. The Improved Harris Hawks Optimization (HHO) algorithm was
used to obtain the optimal configuration of the double-element and the
resulting designs showed a significant improvement in downforce and drag
performance compared to the baseline designs. Improved HHO was further compared
with other state-of-the-art algorithms for assessing the algorithm's
performance for a problem with highly non-linear behavior, where it was able to
demonstrate its ability to obtain the optimal solutions more efficiently.
