Fusion Message Board

In this space, visitors are invited to post any comments, questions, or skeptical observations about Philo T. Farnsworth's contributions to the field of Nuclear Fusion research.

Subject: Cooled Grids
Date: Oct 18, 3:59 pm
Poster: Jim Lux

On Oct 18, 3:59 pm, Jim Lux wrote:

I've been doing some calculations on building a grid out of hypodermic tubing so that you can circulate a cooling fluid. For small fusors, it looks pretty grim...

I assumed a .02" ID (22 ga tubing), water as the coolant, a max 100 degrees rise and a length of about a foot (31 cm). For a power of 100 Watts into that length of tubing, you'd need about .24 g/second of coolant, which would have a pressure drop of approximately 2471 kPa, or 360 psi. The pressure loss itself will put heat into the system, which was not calculated.(its about 1/2 watt)

Making the tube smaller makes the pressure drop skyrocket, making it a bit bigger, makes it drop a lot.

In any case, it isn't entirely out of the question.. particularly if you allow a higher temperature rise... say 500 degrees, which greatly reduces the flow velocity and pressure drop (to about 17 psi)...