Sugar Shot to Space Double D sugar propellant coreless grain test скачать в хорошем качестве

Sugar Shot to Space Double D sugar propellant coreless grain test

Small motor test (K-class) of our new "Double D" geometry sugar propellant grain. A total of four pounds of KNO3/sorbitol in a 65/35% ratio. Propellant surface was inhibited with polyester resin and hollow quartz micro-balloons except for two lengthwise sides for the burn to take place (see photos of 12 grains at the beginning of the video). Nozzle throat was sized for a 6-grain motor so low pressure (200-300 psi) was expected with this first motor test. The low pressure also resulted in a low exhaust velocity and the large amount of slag build up on the nozzle and flame diversion plate seen in the post test photo at 5:15. Next tests will use 4 and then 6 grains (L and M-class motors) that the nozzle throat was designed for. Ignition proved difficult since the top and bottoms of the grains are also inhibited with polyester and several things were tried and a thin 'ring of APCP propellant' cut from a 38mm grain appeared to be the solution for ignition. The sliver plate (seen to the right of the nozzle at 5:30) is designed to catch and prevent large pieces of propellant that could become detached from blocking the nozzle. It is a disk of steel about 3mm thick with holes equaling 400% of the nozzle throat area. This initial test using 2 grains was successful for testing these three objectives: 1) the new Double D grain design, 2) igniting the polyester inhibited grains and 3) the sliver plate. The next two tests will be conducted with the larger 4 and 6 grain motors. Four grain test can be seen here:    • Mach diamonds in 4 grain DD 89mm Sugar Sho...