Mixed convection phenomena inside a simplified tyre geometry

To further current methodology and understanding regarding heat transfer in motorsport tyres, RANS/URANS methodologies were created and compared to investigate natural and mixed convection phenomena in a simplified tyre geometry subject to a thermal gradient from rim surface to tyre crown. At a Rayleigh Number (Ra) of 5.02 ×106 natural convection phenomena were investigated and variation in outer cylinder Nusselt Number (Nu) was quantified. With rotational effects at a higher Rayleigh Number of 1.094×107, a weak correlation between Reynolds Number (Re) and outer cylinder Nu was found with 21% variation across the whole Re range (4.851 ×105 < Re < 1.698 × 106), with most variation occurring at lower Re. Further, a RANS and URANS methodology were compared for resolution of Natural Convection phenomena. Steady-State and Transient Implicit solvers were compared with minimal variation in results but the transient solver taking 0.709% longer per iteration and 51.06% longer to converge. The transient methodology showed promise however as they did not encounter similar stability issues as steady-state solutions at higher Ra.