TRUE TEC Module (with pics)

[Jorlen]

Short answer: 2.

I am not an expert. But I do recognize two limiting factor of the heatpipes. Hotter pipes means increased pressure which means more of the substrate in the pipe is in gas form all the time. Which lowers the amount of working fluid. I dont know what temperature you will end up with, but its not likely this will have any impact.
The other limiting factor is the rate at which fluid returns to the evaporation end of the pipe. Think about it like this. The more energy that goes into the pipe the faster the evaporation occurs. Thats a linear relationship. Twice the energy, twice the flow of evaporated liquid (gas). The speed at which liquid returns to the hot end of the pipe does not increase in this manner at all. Gravity will help increase flow somewhat, providing the pipes are mounted vertically.
So at a certain point the capillary liquid transport in the wick-structure to the hot end will be less then the gas-transport to the cold end. At this point heat transfer via evaporation stagnates. At this point increasing the load further will raise pipe temperature and if run out of control the problem mentioned above might become noticable.



(edit spelling)

Jorlen, are you saying that if you heat a heat pipe above its maximum wattage it will

1. completely stop transfering heat except for it's outer shell

or

2. keeps transfering its maximum wattage and the excess heat must travel through the outer shell