Not if it is touching the walls of inner or outer alumina tube in places, intermittent contact due to vagaries of original wire winding around inner tube and subsequent large differential thermal expansion so that the wire is quenched in some places but not in others. Would explain the variation in glow that we see (along with slight translucence of alumina tube), and would change as the wire gets hotter and relaxes pre-existing springiness that might otherwise hold the wire in contact with the inner tube - would lead to wire temperature increasing faster than power input would suggest - ie what we see with supposedly increasing COP.
Most likely means of construction is winding wires around an inner tube, or winding them around a different mandrel and then slipping them over the tube. Bonding them to the inner tube is an extra step that (based on inconsistency/variability of surface glow) has likely not been done and for which their would be little initial motive anyway. And massive relative thermal expansion of the wire (~1%) would likely have cracked any ceramic bonding or attempts to rigidly encase the wires or bond them to the inner tube anyway. Differential thermal expansion means that the internal tube/vessel is likely only bonded to the thermocouple end cap, otherwise the external tube would be broken by axial stress due to differential thermal expansion of higher temperature of inner tube compared to external tube. On 16 October 2014 10:58, H Veeder <[email protected]> wrote: > > If the wire inside the reactor was hot enough to glow it should produce a > more uniform spiral glow along the entire length of the tube. > > > Harry > > On Wed, Oct 15, 2014 at 8:19 AM, Robert Lynn < > [email protected]> wrote: > >> Additionally, look at the darkened photo, the wire exterior to the >> reactor sourrounded by cooler materials to radiate to are brighter than the >> bright wires in the reactor. Hard to believe it would be colder inside the >> reactor surrounded by relatively hotter materials that are harder to >> radiate to. I think that is pretty strong indication that it is the wires >> that are the bright areas. >> >> On 15 October 2014 20:14, Robert Lynn <[email protected]> >> wrote: >> >>> I am looking at high zoom at the same photos and finding it easy to draw >>> the opposite conclusion. Confirmation bias on both our parts :) >>> I think it is equivocal at best. >>> >>> On 15 October 2014 19:52, ChemE Stewart <[email protected]> wrote: >>> >>>> If you zoom in very closely on the hot reactor photos you can see the >>>> the dark lines are of uniform width, continuity and shade. I am 95% >>>> confident that is the shadow of the coil. The light areas change in >>>> brightness, width, etc. >>>> >>>> On Wed, Oct 15, 2014 at 3:56 AM, Robert Lynn < >>>> [email protected]> wrote: >>>> >>>>> how do you know this? How do you know the the wire is not the >>>>> brightest area? >>>>> >>>>> On 15 October 2014 15:06, H Veeder <[email protected]> wrote: >>>>> >>>>>> Some people suspect that the resistor wire can't be Inconel because >>>>>> they are predicted to melt at the reactor's operating temperature. >>>>>> However, >>>>>> since we know the resistor wire casts a shadow in the alumina, the >>>>>> temperature of the wire remains below the operating temperature and >>>>>> therefore can't melt. >>>>>> >>>>>> Harry >>>>>> >>>>> >>>>> >>>> >>> >> >
