Time-resolved fuel regression measurement function of a hybrid rocket solid fuel integrated by multi-material additive manufacturing

The function of time-resolved fuel regression measurement is integrated into additively manufactured hybrid rocket fuels and conceptually demonstrated through the comparison with optical measurements during burns. This enabled by multi-material additive manufacturing mainly thermoplastic solid a ladder-shaped resistor made conductive thermoplastic. functionalization has many advantages, as indicated its wide range applicability, including grains emerging complex geometries, cost-effectiveness, ease implementation, minimal influence on original propulsive performance behavior. Fuel detected step change in voltage applied to resistor, indicating breakage top surface rung burn. For ignited cases, all breaks were detected, while was also optically measured using high-speed video. Errors observed between time-histories two methods; however, most these errors could be explained distribution camera direction resolution melted layer thickness. Considering uncertainties, remaining that not factors less than ±0.15 mm, corresponding ±1 prototyping fuels.