Lean premixed hydrogen-air flames in intense sheared turbulence and their scaling*

Hydrogen is a potential carbon-free natural gas replacement for gas turbines. However, combustion properties for lean premixed hydrogen flames can differ significantly from natural gas due to preferential diffusion effects leading to thermo-diffusive instabilities. In this work, we investigate the burning rate scaling with pressure and turbulence intensity, which is not well understood. To this end, we present a series of direct numerical simulations in a temporal shear layer configuration at atmospheric and elevated pressure spanning multiple turbulence intensities. The dataset shows how local turbulent burning rates are significantly amplified at elevated pressure, and how increased turbulence intensity further increases local burning rates. We will highlight main features of the turbulent burning behavior of the flames at different conditions. In addition, we will discuss potential scaling of turbulent burning rates with non-dimensional parameters including this new dataset and additional experimental datasets.