SPRE1500 Project

SPRE1500 is both an acronym for Solid Propellant Rocket Engine of 1500Ns and one VGT's major projects.

Purpose and goals

Main goals of this project are:

  • Investigate known fuel combinations
  • Investigate new fuel combinations
  • Have accurate measurements on time, chamber pressure and thrust
  • Achieve a high ISP at a reasonable chamber pressure
  • Achieve good initial/final mass ratio

Formulas testing

In the first large solid propellant rocket motor built by VGT candy fuel was used because of previous experience in casting. Another reason for using candy fuel in the begining is to be able to use it as a reference point for new formulas.

While scaling up from smaller to larger rocket engines, a series of parameters changed.

To test new formulas, a special test burning chamber was designed. In order to characterize fuel, it will be used on the testing stand, changing different parameters: fuel load, critical section size, etc.

Chemical tools Different fuel combinations SPRE1500
SPRE1500 test stand

Engine Testing

Three tests were performed, each with different amount of fuel inside the engine:

  • Test 1: 50% fuel loaded
  • Test 2: 67% fuel loaded
  • Test 3: 100% fuel loaded

The tests are presented in the videos below.

After performing the tests, the results were used to redesign a new engine with maximum efficiency at 100% fuel load.

Test 1 - 50% fuel loaded
Test 2 - 67% fuel loaded
Test 3 - 100% fuel loaded