4. The ratio of area exchange for average distribution

An idea of the ratio of area exchange is introduced to make numerical analysis on the effective area of the material for average distribution and the transfer of the dye liquor and the material.

The ratio of area exchange is defined as an exchange coefficient that is an efficiency of the supply of dye by the exchange of fresh dye liquor by the circulation of the dye liquor or the material, and expressed in equation (1).

Ratio of area exchange=Ratio of effective area×Number of circulation (time/min) (1)