Current Calculations/Joule effect

Hello, I am not sure if this is the correct forum but I have seen a similar post so I am posting it here. I am a student working on my final year project and I have a hit a wall. I needed to calculate the heat-power calculation commonly known as Joule Heating effect.  I have the 316/316L stainless steel tube with 8mm OD as metal tube and I have a variable 30V DC power supply in lab, I need to calculate how much current in amps do I need to heat it to 1000 C, taking in account there might be losses and 1000 C to reach inside the metal tube meaning the material placed inside the tube should experience a 1000 C temperature. I am sorry if this is not the correct forum or place to put a problem, but I am desperate at this point. Any and all help will be greatly appreciated. Thank you.  Regards, Xyrus