I've been brewing BIAB for the past eight months and am slowly transitioning to a more traditional three-tier method. I already use a round Lowes 5-gallon cooler with ball valve/bulkhead as a mash tun.
I'm starting work on a manifold for the bottom of the cooler and I want to make it with two concentric circles. I read through Appendix F of How to Brew and had a question about the design of a two-ring manifold.
Palmer says that a circular manifold for the bottom of a round cooler should have a diameter
D_manifold = 0.707 D_tun
And this would result in equal spacing inside and outside the ring. That 0.707 number is just 1/sqrt(2). That's all good but this result is only good for a single ring manifold.
In other balanced manifold layouts (for rectangular coolers), the area outside the pipe nearest the wall of the tun is only half the area between inner pipes. That decreases the amount of the grain bed that is undersparged at the boundaries. The same concept should apply to a round mash tun, no? In other words, the area enclosed by the inner ring should equal the area between the rings and that area should be twice the area outside the manifold. Right?
I'm starting work on a manifold for the bottom of the cooler and I want to make it with two concentric circles. I read through Appendix F of How to Brew and had a question about the design of a two-ring manifold.
Palmer says that a circular manifold for the bottom of a round cooler should have a diameter
D_manifold = 0.707 D_tun
And this would result in equal spacing inside and outside the ring. That 0.707 number is just 1/sqrt(2). That's all good but this result is only good for a single ring manifold.
In other balanced manifold layouts (for rectangular coolers), the area outside the pipe nearest the wall of the tun is only half the area between inner pipes. That decreases the amount of the grain bed that is undersparged at the boundaries. The same concept should apply to a round mash tun, no? In other words, the area enclosed by the inner ring should equal the area between the rings and that area should be twice the area outside the manifold. Right?
