Sugar Shot Weekly Activity Report: September 19-25, 2011‏

Markus Bindhammer has performed additional research on the mannitol-based eutectic propellant including ignition of the propellant in the hot molten phase, strand burn testing (at ambient conditions), flash freezing of the propellant, as well as density/volumetric calculations. The results of Markus's research continue to be highly interesting: Eutectic Sugar Propellant Research Part IV

Markus continues to show his generous support for SS2S (and sugar propellant development in general) by providing a grant of $5000 USD to fund research of the eutectic propellant formulations. Deemed "ResearchSShot", the goals of these endeavors are foreseen to include:
a) Evaluating safety risks of liquid eutectic oxidizer/sugar alcohol propellants, minimizing safety risks as much as possible
b) Evaluating and comparing performance characteristics between the standard KNSB and KN-NaN-SB or MT (mannitol) propellant
c) Evaluating if complete forward/aft grain can be produced at once (no segments) with eutectic propellant/oven method in regard of exSShot dimension
d) Building 'small' rocket (MSS or smaller) with eutectic oxidizer/sugar alcohol propellant

Rick Maschek has continued dissection and cleaning of the DSS BP rocket motor components. The nozzle was determined to be in excellent condition and fully re-usable.

An analysis was performed which indicated a possible reason for the much greater degree of erosion of the nozzle ablative liner that was seen, in comparison with MSS. The propellant mass flux was calculated for both DSS BP and the MSS motors. The "mass flux" is the combustion product mass flow-rate per unit area of the grain core. It was determined to average over 5x greater than MSS during the first second of burn. It is clear that some development work is high on the agenda to modify the ablator for much greater resistance to erosion.

  

Hans has completed a draft report dealing with the pairing of pyro devices and flight controllers for DoubleSShot. Each of the flight controllers have their own characteristics, and the pyro devices should be controlled by the most suitable flight controller for the task. Additionally, the report deals with the nature of the recovery process. The recovery strategy has a deep impact on the chute deployment criteria, which in turn affects which flight controller will be most suitable for deployment of each chute (drogue & main).