P1: Nitrous at Balls in '09

Motor Project

PBAN Fuel Grains

Last Update, 5/30/08 by Stephen Daniel

Introduction

This page documents the PBAN fuel grains we use.

Information on our original PVC fuel grains is here.

Design

The PBAN fuel grains are built in two steps. First we create the liner. We start with the desired length of PML phenolic tube. We cut a slit length wise on one side and then glue the liner back together. This reduces the diameter from x.xx" to x.xx" so it will fit in our motor.

The second step is to cast PBAN into the liner using a wax coated wooden rod as mandrel to form the core. The PBAN is mixed with 1% carbon-black by weight to improve regression during burn.

Advantages of this design:

• The liner and casting tube are one and the same, reducing the number of custom-made tubes we need. We also get a liner that is guaranteed to support the pressure of the injector bulkhead.

Disadvantages:

• Relatively expensive, both in $$ and labor.

Construction