ME 501

Corey Roberts

Leo Montgomery

• Unity IV background• The Problem• The ANSYS Model• The ANSYS Results• Things Learned

Summary

Unity IV

A multi-university effort to design and launch a hybrid rocket to an altitude of 100,000 feet.

• Completed in 1995• Flew to an altitude of

4500 feet• Demonstrated

feasibility of hybrid rocket

Stage 1

• Launch date set for September 2001

• Will fly to an altitude of 10,000 feet

• Will prove final design concept for 100,000 foot launch

Stage 2

• Airframe• Avionics• Oxidizer

• Recovery• Testing• Motor

• Fueling

• Delivery of Oxidizer to Motor

• Abort Capability

Oxidizer Team Responsibilities

How will the motor mounting plate behave when the rocket accelerates?

The Problem

Weight of motor

Forces acting on plate due to moment of motor

Shear forces due to weight of motor

• Dynamic or Static?

• 10g loading

• Moment and Shear forces

• Constraints

Modeling

• Imported from Pro-E

• Shell Elements

• Free Mesh Resulting in 1914 Elements and 2045 Nodes

ANSYS Model

• Max Stress was 2682 psi

ANSYS Results

• Max Deflection was .00868 inches

• Max Deflection Occurred at Upper Bolt Hole

ANSYS Results

• Plate has a safety factor of at least 5 based on 1100 series aluminum

• Importing models into ANSYS from Pro-E is very easy

• Shell elements can greatly reduce the number of elements in a plate with bending instead of 3D brick elements

Things Learned

• Actual dynamic loading analysis

• Include interaction of plate with support struts

• Finer mesh to get actual stress concentration

• Find material type used to make motor plate

Improvements