X-Message-Number: 2026 Date: Thu, 25 Mar 93 14:29:15 CST From: Brian Wowk <> Subject: CRYONICS Freeman Model Tim Freeman's idea for modelling the edges and corners of the room as sections of cylinders and spheres is exceedingly clever. I immediately proceeded to implement it and discovered that the heat flow in the limit of very small radii for both spheres and cylinders is zero! Oh well. Current Summary of Heat Flow Calculations for 5m x 5m x 3m Room with 1m Trymer Insulation: Flat Wall Approximation, Uniform Room-Temp K Value: 347 watts, 128 liters LN2 per day. Flat Wall Approximation, K Proportional to sqrt(T): 297 watts, 110 liters LN2 per day. Spherical Room (R1=2.17m), K Proportional to sqrt(T): 434 watts, 160 liters LN2 per day or 500 watts, 180 liters LN2 per day if I take inner surface area as 4*pi*R1^2 instead of 110m^2 of the actual room. I am satisfied for the time being that I have the heat flow calculations under control. I think 200 liters per day is a good estimate for the LN2 use. Besides, I have a thesis to write too! --- Brian Wowk Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=2026