I was given an oven that comprises of several cylinders that fit inside one another. The innermost cylinder is a Molybdenum oven that will hold a sample of metal. A ceramic cylinder fits over this. A tungsten wire heating element is wrapped around this cylinder. Two more ceramic cylinders fit around this, and then lastly a Molybdenum shield. I am going to be raising the temperature of the Tungsten wire to 900°C. My question is this: how can I estimate how much current to run through the Tungsten wire to reach 900°C? I know that P=I^2R. I know the resistance of the Tungsten wire. The total power needed is going to equal the sum of the heat transfers (I think?). There is heat transfer by thermal radiation and thermal conduction. I have included a picture of the oven for reference. (Note that in the picture, the wire is not wrapped around the ceramic with threads). Please help me!