RELEVANCE OF REYNOLD’S NUMBER IN FERMENTATION TECHNOLOGY

I personally think that there is too much of irrelevant engineering in fermentation technology. The obsession with mathematical equations, models by engineers into fermentation technology just add further to the mysticism of fermentation. It only helps in making the subject of fermentation technology so esoteric and beyond the reach and understanding of most people including the engineers themselves. After all, the abuse of irrelevant engineering and mathematics only serve in trying to make “sense” out of “non sense”. The logic is simple enough. How can you ever claim to control and optimize the fermentation process if you have very little understanding of the variability of the process?
Yes! Such mathematical and engineering studies and experiments will still data or rather “erroneous data” which one can still try to make some sense out of it. The end product will yield wrong and erroneous conclusions. At this point I am not saying that all the engineering or mathematical input are useless or irrelevant.
The trouble is there is a persistent and irritating trend by chemical engineers and biochemical engineers trying to justify their intrusion into the field of fermentation technology and not vice versa! Good examples are the adoption of unit processes in downstream processing. In a feeble bid trying to improve the engineering or mathematical input into fermentation technology they even try to apply Monod’s equation, Lineweaver Burke into the fermentation modeling! How relevant or significant input these contributions are is another question.
We are thankful for the engineers in helping build or design the fermentors we have on the market now. But looking with perspective over time we see there is no real significant development or advancement in the design and structure of fermentors from the days of Fleming industrial production of penicillin. What we are having now are in fact “living fossils” of the old antiquated fermentors. Nothing much has really changed!
Let us look at the application and relevance of Reynold’s Number to fermentation technology.
Historically, the exposition of Reynold’s Number is the keystone to fluid mechanics. It is more and observation on the nature of fluid flow which includes air and liquid such as observed in wind tunnel, aerodynamics and in trying to explain the transformation of simple laminar flow to complex flow turbulence
The application of Reynolds number might be of relevance in aerodynamics of flight where it is necessary to understand the behavior of objects exposed to high speed wind velocity and turbulence. But I cannot really see the relevance of Reynolds Number at the level of fermentor where we are really dealing at low rpm. In fact, laminar flow is not really sought after in fermentor as turbulence is needed to improve the various mass transfer processes during fermentation
To complicate things further the behavior of the fermentation broth is complex in terms of its phases and changes that occur as a function of time. The rheology of the fermentation broth is complex and almost no two fermentation broth are the same. In fact there are so many variables involve which will influence the Reynolds number such as size, geometry, broth type, media composition and even the composition of microorganisms used in the fermentation process
There for do we really need to apply Reynolds Number in the study of fermentation process or is it just a vestigial reminder left by the engineers for us just like the mysterious smile of the sphinx?

Type rest of the post here.