The oxidizer-to-fuel ratio for solid propellant rockets refers to the ratio of the mass of the oxidizer to the mass of the fuel in the solid propellant composition. This ratio is a critical parameter for designing and controlling the performance of solid rocket motors. In solid rocket propellants, both the fuel and oxidizer are intimately mixed together in a solid form, and the O/F ratio is defined by the mass of the ingredients used.
The mass-based O/F ratio (Φ) is calculated by dividing the mass of the oxidizer (m_ox) by the mass of the fuel (m_fuel). In SI units, both masses should be in kilograms (kg). The formula is as follows:
where,
- Φ is the O/F ratio, or, oxidizer-to-fuel ratio
- Mox is the Mass of Oxidizer
- Mfuel is the Mass of Fuel