I wrote:
> (6 bar = 0.6 MPa. This table shows hydrogen density at 1 MPa at 25°C is > 0.8 kg/m^3. This is 0.034 kg, or 0.043 m^3 = 43 L) > Oh wait. It gets a lot hotter than 25°C, doesn't it? Granted, the NIST table and graph does not show pressure increasing much between 0°C and 125°C. This graph does not go any higher. 1 MPa goes from 0.8085 kg/M^3 at 25°C down to 0.6061 kg/M^3 at 125°C. I wonder why the pressure does not increase in the graph from Zhang? Am I missing something here? The pressure drops off starting at 1100, then increases, and drops off again a couple of times. Someone suggested that is a leak which they are refilling. This person thought the gas might be igniting, which causes the excess heat. It would ignite in the vicinity of the outer wall thermocouple, if it ignited anywhere. I thought this pressure fluctuation might be the nickel powder absorbing and desorbing the gas, but I wouldn't know. The text does not mention adding in new gas. - Jed
