Gravitational collision efficiency of LMFBR aerosols

The development of an approach to obtain gravitational collision efficiencies for non-spherical post-HCDA LMFBR aerosols is discussed and the correct formulation of the gravitational collision kernel for non-spherical aerosols is presented. Using mass equivalent diameter as the defining length in the gravitational collision kernel, the aerodynamic shape factor, k, the density correction factor, α, and the gravitational collision shape factor, β, are used to correct the collision kernel for the case of collisions between aerosol agglomerates. A specific case of collisions between agglomerates modelled as oblate spheroids and spherical LMFBR aerosols has shown that the shape factor β needs to be investigated further if the growth in size of LMFBR aerosols due to the gravitational coagulation mechanism is to be modelled accurately. In this context, the HAARM-3 shape factors currently used to make corrections for non-spherical aerosols are briefly reviewed