A burn rate modifier can be any material that changes the speed at which a propellant burns. Most modifiers accelerate the burn rate. The one that I use in this topic slows it down.
Baking Soda
Baking soda’s ability to slow a combustion reaction without significantly effecting combustion stability makes it an ideal burn rate modifier for black powder propellants. It does so by adiabatically cooling as it expands into a gas. By decreasing or increasing a propellant’s baking soda content, you can speed up or slow down its burn rate, and fine-tune a rocket motor’s performance. A brief reference in John Conkling’s topic. The Chemistry of Pyrotechnics, prompted me to experiment with it. and I was so happy with the results that I’ve included baking soda in all the propellants in this topic. Baking soda’s chemical name is sodium bicarbonate. Its chemical formula is NaHCO,. and you can buy it at a supermarket (Figure 6-41). I’ll mention it again in topic 7. but it requires no preparation. You’ll be using straight from the box.
Figure 6-42. One gallon cans of acetone and denatured alcohol.
