You weren't using hydrogen. Hydrogen has an almost invisible flame. Just look at the main engines on the shuttle when it launches.Are you sure that's Hydrogen he was using? The flame on my equipment was blue in color, plenty visible, and it was used when spraying aluminum specificly because it was cooler than oxy/acetylene.
Last updated April 6, 2005.
Flame temperature is not as simple as it sounds. It depends on many factors, such as:
* Whether the (gaseous) fuel flow is laminar (smooth) or turbulent
* Whether the fuel and oxidixer are premixed, or simply diffuse together while burning
* Whether the flame is "adiabatic", meaning that it does not lose heat. While impossible in practice, the theoretical adiabatic temperature is often quoted.
* Where in a (laminar) flame the temperature is measured
* For flames in air, the temperature, humidity, pressure, present gas mixture, etc. of the air
* The mixture of fuel vs. oxidixer in use. For example, an acetylene/oxygene flame may be neutral (equal mix: complete combustion, white rounded cone); carburising (excess acetylene: large smoky yellow flame); or oxidising (excess oxygen: short, sharp inner cone, deeper purple hissing flame).
Sites discussing practical welding and similar tasks tend to give much lower numbers than science-oriented sites, probably because of rapid heat loss in typical use. A number of sites warn that measurements done with thermocouples can be wildly inaccurate. More definitive information is available in the North American Combustion Handbook.
As a general practical guideline, consider one site's list of these heats for their jewelers' (gas/oxygen) torch:
* 2200°C = 3992°F, for Propane/Oxygen
* 2927°C = 5300°F, for MAPP Gas/Oxygen
* 2700°C = 4892°F, for Acetylene/Oxygen
* 3200°C = 5792°F, for Hydrogen/Oxygen