Before and after WhirLpoOL HydroMeTer Readings

[MandingaBIAB]

I haven't observed stratification with my BIAB system.... It seems that gravity, viability and viscosity are constant in all depths of the kettle, high and low. But, with that being said, I try to give the wort a gentle stir to keep the heavier sugars from accumulating near the bottom of the kettle so it could be a function of stirring that keeps my wort the same.

 

[ajdelange]

Could BugHunter be seeing an issue of temperature stratification, where there is a hot spot at the top of his kettle caused by a vapor cushion or the like? If he does not have the assumed equilibrium of temperature throughout his kettle, would that be why his measurements do not match the expectations?

Yes, I suggested that with a possible mechanism in #22 but wasn't too enamored of that explanation as even though the wort would be denser at the top the mole fractions of the constituents would be the same throughout. Perhaps there is some subtlety I'm missing in that reasoning.

 

[jmpreiks]

...the wort would be denser at the top...

Did you mean denser at the bottom?

 

[ajdelange]

No, under this hypothesis, which is, remember, only a hypothesis, the wort at the top is cooler and thus more dense. Now the denser wort isn't going to stay there very long and will, in pretty short order, sink to the bottom and in so doing mix with the lighter stuff there. At the same time the lighter stuff in contact with the jackets will rise so, until the jackets cool to the same temperature as the wort, the convection currents will still flow, lighter wort ascending the sides and denser wort sinking in the center. Mixing will continue though at a slower rate than during the boil.

 

[GotPushrods]

Forgive me as I haven't read the entire thread, but it seems like there might be 2 phenomenon being discussed here.

There is stratification, then there is just incomplete mixing. I and many others have seen 'strata' when one density wort is transferred onto/under another. However I have never witnessed homogeneous wort which is thoroughly mixed become stratified once again.

Was the OP just about 2 worts that may have never been properly mixed in the first place?