mattsawyer

I'm Matt. I like to build things. I am curious about most stuff and want to make better stuff as a result. That and entertain/educate my daughter. Most of the kitchen is filled with various scientific experiments. Some experiments include 'how to drive my wife nuts'. I am succeeding at this presently by leaving jamjars with 'stuff' inside them around the place. She MUST NOT THROW IT OUT.

I'm a newbie here and it has been a long time since I did complex science and I would be grateful for any help and expertise on my problem. I am looking to build a wood burning pizza oven in the middle of no where with no services/water/etectricity etc and hope to use it to also heat some water. My design basically is to sandwich a 10m coil of 10mm diameter copper pipe in the floor - sandwiched between two layers of firebricks. I have looked elsewhere on the net and coiling a copper tube either inside the oven or within the walls of the oven doesnt seem the best idea due to the problems of direct heat on a copper pipe, corrosion and oxidisation etc. I think that sadwiching the coil between firebricks would give a more even distribution of the heat. I have three thicknesses of firebrick and will be doing some experimentation to see which would work the best above and below the copper pipe. This will tell me the temperature of the non-heat side of the brick. The temperature of the wood burning/pizza ovens can get up to 800'c. The hot water system would be an unvented system as i think there is the likelihood of rapid boiling/superheated steam accumulation and the subsequent risk of explosion in a sealed system. My question is - assuming that I can have a constant temperature on the copper pipe, how can I work out the speed of flow of water through the pipe to have a temperature of say 90'c (the termerature is not critical) water coming out. I cannot regulate the temperature of the oven but I can regulate the flow of water to ensure it doesnt boil. As I have to transport the water to the site myself, I want to try and work out if I would need 1 litre, 10 litres, 100 litres or 1000 litres. The wood burning ovens can stay hot for upto 10 hours. If the water ran dry and the copper pipe was exposed to 200'c heat for several hours would this cause any long term problems ? Are there any easy to use graphs showing heat loss over time from copper to water for varying temperatures ? I assume that at 400'c that the heat transfer would be far faster than at 200'c