Rectangular Mash Tun versus Round

[mgortel]

I have been using a homemade rectangular cooler as a mash tun. I get different mash temp readings in different places in the cooler....I am sure because of the non-symmetry of the cooler and heat transfer. (i.e. corners for example)

I assume a round mash tun will give a more consistent temperature throughout.

Wondering what others experiences are with this.

 

[ancientmariner52]

Any insulated vessel will lose heat to the surrounding enviroment. The mash nearest the outer surfaces will cool faster, of course.

A cylindrical container has a smaller ratio of surface to volume than a rectangular container of the same volume, so will lose heater slightly slower. However, the center will always be warmer than the sides, regardless of shape.

Sorry for the thermodynamics lesson. The point is, you must stir thoroughly before checking temp, because the instant you stop, temp differences will develop in any shape of vessel.