1965 Experimental Aircraft Assn. "The construction materials for pulsejet tubes should be 347 stainless steel because of the corrosion and high temperatures. In our experiments, we have measured temperatures as high as 1790 F. However, most experimenters cannot afford such expensive materials. We found that 16 guage cold rolled steel works quite well for static experiments. A this temperature the cold rolled steel has very little strength, but it is ample to withstand the combustion chamber guage pressure of 20 psi."Mark wrote:http://www.rayotek.com/Technical-1.html ... -WHY-49575Mark wrote:http://www.csc.liv.ac.uk/~frans/COMP101 ... aumur.htmlbrunoogorelec wrote: Here's a quote from an early 1950s study (I think by NACA) on pulsejet temperatures. 1 degree Reaumur is equal to 1.25 degrees Celsius.
Tharratt, "If we assume the mean operating temperature of a duct is 1,000 K. we are in the surprising position of being able to determine the dimensions of a duct capable of developing a given thrust literally on the back of an envelope."
Pulsejet theory by Franco Marcenaro "If the temperature in our engine is assumed to be (average) 1750 F the absolute temperature will be 2210 R...
The more scientifically minded among you will probably demand how I came up with the temperature value of 1750 F. ....... Scientists must make things complicated but all you have to do is to add the temperature as usually expressed in degrees Fahrenheit and add 460 to get the Rankine degrees (R) used in scientific calculations."
Another pulsejet article "Nickel steels are used in the commercial pulse jets manufactured in this country to resist the effects of the high combustion temperatures which may top 2000 F in the chamber."
Anyway, if you were to use methanol, the combustion temperature would drop and a pulsejet of quartz glass might be feasible. And perhaps a pulsejet could be coerced to run with a blend of alcohol and water making the combustion even cooler.
Mark