Since nitrous oxide will flow through the engine in a two-phase state, obtaining its discharge coefficient is a difficult challenge. This is because the cavitation behavior of the nitrous oxide depends on mass flow, which means we need to enforce the same mass flow of nitrous during a cold flow as there will be during hotfire. However, this is tricky because the nitrous will be emptying into ambient air, which means the dP across the injector will be greater. To offset this, we will use test pintle tips that have less discharge area (less/shorter slots).