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From these results, the flow regime was assumed to be SPI and the coefficient of discharge 0.8. From these assumptions, the ideal orifice area could be calculated and used to determine orifice geometry. An additional orifice was added at the base of the pintle tip to prevent tip melting; if there is no hole there, the nitrous will stagnate and be trapped underneath the radial orifices, causing it to flash boil, which then lets the hot gas melt the tip. The hole was sized based on the difference between ideal and actual orifice area.
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