A term used in the continuous operation of a fixed volume vessel supplied with a constant flow stream of material and an equal amount leaving, and defined as the ratio of volumetric flow rate, Q, to volume of the vessel, V:
(p. 109) In the continuous cultivation of microorganisms in a bioreactor containing viable cells, fresh nutrients and limiting substrate promoting growth are supplied while inhibiting metabolic products are withdrawn at the same rate. A material balance for cells, X, and limiting substrate, S, for an ideally mixed bioreactor is:
where SO is the concentration of supplied substrate, μS is the growth rate, and YX/S is the yield coefficient. The SI unit is s−1.