ASCE has honored the writing team of Haochen Li and John Sansalone, Ph.D., P.E., M.ASCE, with the 2023 Rudolph Hering Medal for the paper “Benchmarking Reynolds-Averaged Navier-Stokes Turbulence Models for Water Clarification Systems,” Journal of Environmental Engineering, September 2021.  

The researchers apply common RANS models to steady-flow clarification. Results are examined against high-resolution large-eddy simulations (LES) by the high-order spectral element method (SEM) Nek5000 and laser Doppler anemometry (LDA) for three deflector configurations: (1) one-sided, (2) two-sided, and (3) no deflector. RANS model’s relative mean differences with respect to LES range from 13.9% to 41.4% and 32.7% to 105.1% in streamwise and vertical velocities, varying with configurations. LES predictions were improved from Reynolds-averaged Navier-Stokes (RANS). LES and RANS differences transcend hydrodynamics and persist for particulate matter (PM). Across configurations, RANS models of PM separation are predominately lower than LES. RANS model variability is discerned across clarifier configurations, decreasing with increasing PM diameter. 

The Rudolph Hering Medal recognizes outstanding papers that contribute to the advancement of the environmental branch of the engineering profession.