Aggregation kernel orthokinetic

A semi-empirical form of orthokinetic aggregation kernel due to Thompson (1968) is adopted for illustrative purposes only, viz. 

This is often referred to as the orthokinetic aggregation kernel. 

These kernels are valid for inertialess particles (i.e. Stp = 0) and can be extended to finite Stokes numbers only by employing ad hoc corrections. For example, Ammar Reeks (2009) derived for the kernel proposed by Salfman Turner (1956) a correction that is based on the local Stokes number. The relative importance of perikinetic aggregation versus orthokinetic aggregation is quantified by a Peclet number ... 

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