Red Kiosk: water squirts out with more force and further
Yep, that's basically Bernoulli's principle (if you want to be fancy). Although, when the heat flow gets constricted, like a balloon being squeezed, the flow seeks an easier path. In this case the compressed flowing gas probably uses more of the slot toward the back and front to reach it's goal of hot air rising.
Red Kiosk: Is there a difference in sound when you raise the plate?
I didn't detect any sound difference.
JT: As we raise the steel plate/stone (increase the gap between the bottom of the plate and metal lip of the oven) we put the crust closer to the flame. The heat is more concentrated as we get closer to the ceiling.
I do think this a potentially complicated flow. From a velocity perspective, the torch gets squeezed as it flows between the turntable and the heat shield therefore the speed of flow increases (and some hot gas diverts to other available slot space as above). After making it through the gap, the hot gas reaches an expansion chamber and slooooows down. After that, I get confused.
Is the heat squeezed mostly to the back (b/c of air drawn in for burning and confluence with the rising flame kind of like a prophylactic backfire gets drawn in and upward by the forest fire). If "squeezing to the back" of the Blackstone Oven were to happen, the hot air mixing near the topstone would be less likely to shoot over to the left side. It all sounds good, and now that I checked, I do see some evidence in the photos that the rim char on test pizza skins extends more toward the back as the platter height increases. (But you'll have to trust me on this b/c of size limitations in the posted photos.)
I can make up a story that the mixing near the top stone flows toward the front panel, backs up b/c the front lip is lower than the stone, and the backpressure causes it to billow down toward the skin on the stone. Hopefully you're rolling your eyes at this point, b/c I certainly am.
I don't like that glow bar, but I do like the way BS bakes out of the box. My take on the glow bar is that it certainly impedes the heatflow to the cooking chamber. Like Chau's first ChauFlector test, where he over-bent the deflector, backpressure likely caused the heat to back up and billow around the platter and over charring the rim -- maybe there is a billowing effect created by the glow bar which results in a uniform platter temperature. Or maybe not - I haven't cut the glow bar yet. If someone w/ a cut glow bar has noticed a bit less uniform heat on the stone, pls post.
One thing that I did observe when the platter was set low (1/8") was that the glow bar diverted flame to the backside of the heat shield.
I do think there may be merit to red kiosk's "scooped up" argument suggesting that more heat flows as the stone height increases.
In sum, I don't really know - which is why I asked for ideas. If someone can "nail it", let's name the elevated platter principle after them.