Hey peoples. I'm trying to setup a fissile reactor so that once it reaches a certain temperature, the fuel rod inside will pop out, so that the water will then cool it down. Once it is down below a certain temperature, then the fuel rod would go back in. I've tried a few ways that I've google, however none achieved any help... atomic waste went everywhere. Is there a way to do this whilst still using water and the turbines to make a sufficient source of electricity. All help will be much appreciated.