smoke/flame media is uncompressed and takes up roughly the same space as an equivalent dpx file.
I forget how much a single HD dpx frame is, but I think it’s around 9-10 meg at 10bit color depth. Multiply that by your frames per second and go from there.
I don’t know why, but I’m always amazed when the math works out. We had to bring in some massive amount of media and my engineer figured out exactly the space needed. It was like magic to me. Haha.