> Aloha, > If you are using that solution for oxidizer, what is the viscosity? > Will you need a large opening in your injector? If so, what will you > do to make sure you have even distribution instead of chunky flow? > What pressure will be needed > for good atomization? > Helium blowdown, or a pump? > Things to consider. > > Larry >
-G'day Larry, I have had many emails from people about this idea, which is great. Looks like a guy has been experimenting with a similar concept for over 20years;-) This is good and may have to drop the phrase "new" (although it's still quite new because it's not being used in a significant way) and enlist his help:-).... One problem that is apparent is to achieve even combustion. This was evident with tests of the reaction of Mg and oxidizer solutions. If you spray a fine jet of oxidizer onto the burning Mg grain, you get a localized increase in burning rate. The reaction is so violent that this does not seem to be a great issue as long as the grain surface is not cooled too much that it results in extinguishment. Of cause, we need even combustion and so, even pray of the oxidizer over the entire grain is better and should result in more stable combustion. How to achieve this even distribution is unknown at this stage. Ideas from impinging many jets of oxidizer at the bulkhead end of the motor to achieve reasonable atomization would help. Other ideas include having a SS tube that is positioned within the central cavity of the fuel grain and using many-many tiny holes to produce very fine stray. The limitations of this approach may be in the scaling to larger grains:-( Initially, will need to use the viscosity of water to start the design off for the injectors as, no data is available to me for water/oxidizer solutions (although I'm sure it exists somewhere). I opt to test it out and measure the flow rate. It's a good question, what pressure will be needed for good atomization? Any help to determining this is great. We may have to just test the atomization out. Although the dissolved oxidizers increase the density of the solution significantly, which means the jets of oxidizer have lots of flow energy and so if the jets impinge, they should shatter and atomize. But my knowledge is limited here. I have experience atomizing molten AN but none with injectors in rocket motors. To feed the oxidizer, we will off cause use blowdown. Most likely using Nitrogen contained within the ullage of the tank. However we should for the initial static tests control the tank pressure with a regulator. Any suggestions most welcome:-) Cheers, Steve ----- Stephen J. Holden Owner/Founder Mechanical Engineer Australian Experimental Email: [EMAIL PROTECTED] Web Page: http://www.australianexperimental.com.au _______________________________________________ ERPS-list mailing list [EMAIL PROTECTED] http://lists.erps.org/mailman/listinfo/erps-list
