A gas generating composition (GGC) was designed with Guanidinium azotetrazolate (GZT) as fuel and Ammonium perchlorate (AP) as an oxidizer for burst testing of nozzle closure at rig level, simulating solid rocket motor ignition transient and propellant flame temperature. EXPLO5 software code was used for formulation studies. The selected GGC formulation was subjected to thermokinetic analysis for understanding the thermal decomposition behaviour as well as evaluating kinetic and thermodynamic parameters of decomposition.The non‐isothermal kinetic parameters of the composition over the extent of conversion were determined using two isocoversional methods viz; Flynn‐Wall‐Ozawa (FWO) and Kissinger–Akahira–Sunose (KAS). GGC in pellet form was fired using a pyrotechnic pressure generating device (PPG) in test rig level with nozzle closure. The nozzle closure was burst opened at a pressure of 0.985 MPa with a pressurization rate of 10.3 MPa s−1.

Guanidinium azotetrazolate (GZT) based cool gas generator is being successfully used for a variety of applications in space exploration systems. In this work, an air heater igniter with a cool gas generating composite propellant (GGC) based on GZT was designed and developed for residue less combustion of fuel-air-oxygen mixture of the scramjet propulsion test facility. GGC was formulated with guanidinium azotetrazolate as fuel and ammonium perchlorate as oxidizer. The composition of GGC was selected based on theoretical study carried out using REAL software and the finalized composite propellant was processed and cast under vacuum. The thermal, ballistic, mechanical and safety properties of the GGC were determined. The propellant showed acceptable mechanical properties, fit for use as a pyrogen igniter composition for the present application. Hyphenated TG-GC/MS technique was used to reveal the evolved gas composition during decomposition. The propellant showed limited dependency of burn rate on pressure, with 'n' value of 0.61 and 'a' value of 1.361 mm s À 1 MPa À 1 . Based on the propellant energetics and experimentally devised burn rate law, a pyrogen igniter with an end burning propellant grain configuration, was designed, processed, and tested at stand-alone mode.