Again one injector post

This time again for the AN injection. Well The ADN (Ammonium dinitramid) looks nice, but it is considered unavailable. Both technically and financially. The CAN (Ceric ammonium nitrate) has a melting point of about 108°C, so it could make a very nice alloy with the AN. Especially for its high reactivity with organic compounds.

Back to the injector or spray. One site here summarizes about all the injector nozzle types I have considered so far.

"Atomizer designs include co-axial air assist, liquid and air swirl, pizo-electric induced fluctuations, effervescent bubble atomization, rotating cup and disk. Electrostatic charging of droplets allows deflection of droplets in flight and avoidance of deposition on surfaces"

Well I did not consider electrostatics in helping the dreaded AN crust problem. Some possible solution is to lay the omega chamber in the piston with thermally insulating catalytic material, so that the AN could be deposited and boiled off and decomposed in case it comes in direct contact.

In reply to a question: What is the effect of cerium oxide to fuel?

I recently answered to the question on wikianswers

What is the effect of cerium oxide to fuel?

Short answer is: none. At ordinary room temperatures is the ceric oxide powder rather inert. It has the potential to oxidise various other chemicals and materials, reduce nitrogen oxides for example, but you will not see any measurable effects in room temperature.

The cerium oxide is inert. The point when it becomes interesting is at higher temperatures when it can oxidize carbon for example at temperature much lower than the carbon will usually burn. Another useful property is that it will reduce nitrogen oxides and take the oxygen to form its ceric oxide state. This is used in car catalysts due to good efficiency and favorable price. Yet another use - which can be derived from wikipedia information already is chemical reaction with laughing gas - N2O to form really strong, orange oxidiser (NH4)2Ce(NO3)6 - ceric ammonium nitrate. I plan to test it in a rocket engine fuel soon.

Just to note - many combustion processes, whether in furnace, cars, rockets can not be enhanced, taken more power from them, because of the limited speed of reaction. That is where catalysts take place. Ceric oxide can act as a catalyst. When reacted with certain nitrous oxides it can take form of another chemical composition which acts as a strong oxidiser potentially increasing the speed of the reaction even further.

It is said that the east german racers used ceric oxide fuel additive to improve combustion of their vehicles on some races and thus cheated, but closer information on their setup is hard to find. In general ceric oxide will improve combustion if the combustion has tendency to form carbon particles, like in diesel engines or race engines with high fuel:air ratio.

The maximum surface area of ceric oxide nano-powders ranges from 35-70 square meters per gram of the powder. Ordinary polishing powders do not have such large surface area since they are aimed for polishing, not as a catalyst.