M. Seesselberg et al., STOCHASTIC SIMULATIONS AS A BENCHMARK FOR MATHEMATICAL-METHODS SOLVING THE COALESCENCE EQUATION, Atmospheric research, 40(1), 1996, pp. 33-48
Common mathematical methods for the treatment of droplet coalescence a
ttempt to approximate the coalescence equation in various manners. Som
e of these methods may yield different results when applied to realist
ic coalescence processes with complicated kernels. Thus, independent a
ccuracy checks are desired. In this paper a modification of Gillespie'
s stochastic simulation algorithm is presented which yields reliable r
esults at the price of an extensive CPU-time consumption. This algorit
hm is recommended to perform benchmark calculations to test the qualit
y of faster methods for the numerical approximation of the coalescence
equation. As examples for these approximation techniques a slightly m
odified discrete method of Kovetz and Olund and the integration scheme
of Berry and Reinhardt are examined. Simulations carried out by the s
tochastic algorithm reveal that the integration scheme of Berry and Re
inhardt is more accurate than the discrete method.