“Bodenstein number”的意思、由来-开放百科全书

词条

Bodenstein number

释义

Determination of the Bodenstein number
References

{{Infobox physical quantity
| name = Bodenstein number
| symbols =

| dimension = dimensionless
| derivations =

}}

The Bodenstein number (abbreviated Bo, named after Max Bodenstein) is a dimensionless parameter in chemical reaction engineering, which describes the ratio of the amount of substance introduced by convection to that introduced by diffusion. Hence, it characterises the backmixing in a system and allows statements whether and how much volume elements or substances within a chemical reactor mix due to the prevalent currents. It is defined as the ration of the convection current to the dispersion current. The Bodenstein number is an element of the dispersion model of residence times and is therefore also called the dimensionless dispersion coefficient.^[1]

Mathematically, two idealized extreme cases exist for the Bodenstein number. These, however, cannot be fully reached in practice:

corresponds to full backmixing, which is the ideal state to be reached in a continuous stirred-tank reactor.
corresponds to no backmixing, but a continuous through flow as in an ideal flow channel.

Control of the flow velocity within a reactor allows to adjust the Bodenstein number to a pre-calculated desired value, so that the desired degree of backmixing of the substances in the reactor can be reached.