Ice Box Insulation
Linked to the question of refrigeration. 12x8x8 foot walk in freezer, insulated with 8 inches on all sides of urethane
have a value R 6.7 inch. In my novel, and has no electricity, and people pack the freezer at 90% with hail collected to preserve food. Therefore, it is no longer a walk in 'fridge', but on foot icebox. About 700 cubic feet of ice, eight inches on all sides of the I-6, 7 inches of insulation. Suppose ambient temperature = 75 degrees Fahrenheit. If you open the doors of the minimum times a day to reduce the hot air to get inside, how long LATTER ICE? They are trying to maintain approximately 70 cubic feet of frozen food or at least cool enough to be sure. I'm trying to find out how often to greet feasible. Or should provide an iceberg in place? The end of ice large enough to be useful? Should I use several refrigerators more small, large or less? You can always change the size of the hike in units. March 4, 1908 to 0538 hours, GMT.
Using a whole boatload of approximations, A = 2 (12 * 8 + 8 * 8 + 8 * 12) = 16 * 32 = 512 m ^ 2 t = 8 "R = 8 * 6.7 = 53.6 The heat load is Q = 512 (75 -32) / 53.6 = 410.75 Btu / hr 12 * 8 * 8 = 768 cubic feet we are talking about 68 cubic feet of food. Assuming cubic-pack contains 700 cubic feet (0.5235988) (700) = 366.5191 cubic feet of ice (0.9167 g / cm ³) (1.2 lb / 1000 g) (2.54 cm / in) ³ (1,728 in ³ / ft ³) = 57.10772 lb / ft (cubic feet 366.5191 ) (57.10772 lb / ft ³) (80Btu/lb) = 1,674,485 Btu (1,674,485 BTU) / (410.75 Btu / hr) = 4076.654 hours = 169.86 days if the door does not open. The melting ice is approximately linear with time, and 24-hr merger would be (24 h) (410.75 Btu / hr) / [(80Btu/lb) (57.10772 lb / ft ³)] = 2.157764 feet cubic, so opening the door once every 24 hours allows the entry of 2.157764 cubic feet of air at 75 ° The heat capacity of air is (1.0035 J / g ° C) (1 cal/4.184 J) (2.2 lb/1000 g) (° F 9 / 5 ° C) = 2.931405e-4 Kcal / Kg (2.157764 m³) (0.075 lb / ft ³) ( 2.931405e-4 Btu / space Audio F) (43 ° F) = 0.002039903 BTU This is negligible but, unfortunately, we must assume that all air is replaced every time you open the door. (1-.5235988) (700 cubic feet) ³ = 333.48084 feet (ft ³ 333.48084) (0075 lb / ft ³) (2.931405e-4 Btu / lb ° F) (43 ° F) = 0.3152655 Btu / That the opening Using another ice 0.00006900676 cubic feet per opening, which is still negligible, so that your planning time is still about 169.8 days. Unfortunately, you can not depend on a hail storm in any town in this period of time, but then you should be able to supplement their food supply by hunting and collection, and perhaps its not so distant ice fountains. At least it gives you time salting and pickling. The infamous square cube law says that their ice boxes should be as large possible. The iceberg is a great idea (pun intended), but you still have to reach plausible transport. You may also have some genius to reach ammonia refrigeration system to make ice oil. Tombstone, Arizona where the Earp was one were there, and was not powered by electricity.
The Mystery of Little Red Riding Hood’s Ice-cream