The above example have shown that COSP can be used to reliably choose, from arbitrary initial values, the tar-retention coefficients which best fit the set of experimental data and which can be used for filters of the same material but different sizes.

It might reasonably be said the COSP represents the first step towards answering the designer's real CFD question, which is often not, 'What will the flow be if I choose these inflow conditions?' but rather 'What inflow conditions will give me the flow that I want?'

COSP has only a modest track record at present. Once its capabilities are recognised by PHOENICS users however, that situation can be expected soon to change.