  A new premixed turbulent combustion model is proposed. It is based on
one-dimensional (1D) filtering of density times progress variable and of the
reaction source term of laminar premixed flame profiles using a filter kernel
which reflects the variation of the slicing area of planar flame fronts as they
move through multidimensional filter volumes. It is shown that these
multidimensional effects qualitatively change the relation between the filtered
reaction source term and the Favre-filtered reaction progress variable compared
to 1D filtering, particularly at large filter widths. Analytical results for
the filtered quantities are achieved by approximating density times progress
variable and reaction source term by suitable Ansatz functions. Filtered data
from Direct Numerical Simulations (DNS) of statistically planar turbulent
premixed flames at different free stream turbulence levels and heat release
parameters is used to develop and validate the model. Two wrinkling factor
models as function of filter width and subgrid turbulence level are proposed.
For small filter widths up to two times the laminar flame thickness, minor
effects from subgrid flame folding are observed. For larger filters, the
filtered reaction source term rises linearly with filter width at a rate which
increases with subgrid turbulence level. The modelled reaction source term as
function of Favre averaged progress variable and filter width shows excellent
agreement with filtered DNS data for all investigated free stream turbulence
levels, filter widths and heat release parameters.
