2024 ASEE Annual Conference & Exposition

The Concept Hybrid Rocket Demonstrator (CHRD), originally developed as a Senior Capstone design project in the Mechanical Engineering (ME) and Mechanical Engineering Technology (MET) programs at Weber State University (WSU), has been modified into an experimental testbed used in high temperature materials rapid screening testing. This high temperature materials research is being directed by the WSU affiliated Miller Advanced Research and Solutions (MARS) center.

Consistent with the typical operational characteristics of a hybrid rocket, the CHRD system utilizes a solid fuel grain and fluid type oxidizer. The solid fuel grain is composed of Acrylonitrile Butadiene Styrene (ABS) plastic produced using simple 3D printing approaches and the oxidizer is gaseous Nitrous Oxide (N2O). As a result of the conversion into a high temperature testing system, the baseline CHRD system, as developed in the senior project series, has undergone modifications and upgrades to develop it into a testbed used to evaluate experimental high temperature materials produced by at MARS on behalf of industrial partners. Of specific interest in the initial phase of the project, were the testing of various Carbon-based additive manufacturing (CBAM) produced converging-diverging (CD) rocket nozzles. Rocket nozzle materials are typically exposed to severe environments of elevated temperature gas flowing at sonic speeds in the nozzle throat developing to supersonic speeds at the nozzle exit, thus they are excellent candidates for high temperature durability experimentation.

Utilizing a team of newly graduated ME and MET students as well as student intern research assistants, the original basic rocket system was modified into an experimental testbed supporting high temperature materials research and numerous CBAM nozzles were produced for evaluation. Phase I of this effort included the addition of a comprehensive instrumentation suite to measure rocket operational parameters for correlation to post-test evaluation of composite nozzle test articles and production of rapid prototype composite nozzles. Numerous test firings were conducted to evaluate both testbed performance and material behavior when exposed to combustion product flow field.

Promising results from Phase I were realized such that additional funding has been committed for a Phase II effort. This new phase of activity will encompass upgrades and experimental qualifications of the rocket testbed operation, instrumentation, and control system. Follow-on materials testing will be conducted for both additional nozzle sections and planar impingement specimens fabricated using various composite fabrication techniques. Phase II will again employ recent graduates and undergraduate research assistants to plan and implement the experimental upgrades.