Presentation on theme: "THIS IS ROCKET SCIENCE: DEVELOPMENT AND TESTING OF A HYBRID ROCKET MOTOR IN A ROCKET PROPULSION COURSE Mechanical Engineering Rowan University 201 Mullica."— Presentation transcript:
THIS IS ROCKET SCIENCE: DEVELOPMENT AND TESTING OF A HYBRID ROCKET MOTOR IN A ROCKET PROPULSION COURSE Mechanical Engineering Rowan University 201 Mullica Hill Rd. Glassboro, NJ th Annual Frontiers in Education Conference San Diego, CA, Oct , 2006 Anthony J. Marchese
On October 4, 2004, SpaceShipOne became the first private manned spacecraft to exceed an altitude of 328,000 feet twice within a 2 week period, thereby claiming the $10 million Ansari X-Prize. SpaceShipOne was powered by a hybrid rocket motor (liquid N 2 O, solid polymer fuel) N2ON2O solid fuel Private Sector Opportunities in Space Exploration Motivation for the Hybrid Rocket Motor Project
Objectives, Design Parameters and Constraints The Hybrid Rocket Motor Design Project Objectives of the semester design project: Design, build and test a hybrid rocket motor. Develop a theoretical model that predicts the performance of the hybrid rocket motor as a function of time. Compare measured performance with theoretical model. Constraints: Oxidizer must be gaseous oxygen (GOX) Maximum Chamber Pressure: 115 psia, Ambient Pressure: 14.7 psia Maximum GOX flow rate: 500 SLPM Minimum initial thrust: 5 lb f Fuel grain outer diameter = in Maximum Fuel Grain Length = 12 in Fuel: HTPB, HTPB/AL, PMMA, PE, UHMW or paraffin
Theoretical Model: This is Rocket Science Hybrid Rocket Motor Design Project AbAb solid fuel ApAp Liquid oxidizer AtAt AeAe PcPc T c, X i, Fuel Regression Rate Fuel Mass Flow Rate Chamber Pressure Thrust Coefficient Thrust Specific Impulse Characteristic Exhaust Velocity Specific Heat Ratio
Theoretical Model Results Hybrid Rocket Motor Design Project The detailed analytical model was used to predict the variation in fuel flow rate, O/F ratio, chamber pressure, thrust and specific impulse (I sp ) with time.detailed analytical model
The theoretical hybrid rocket motor model was also used iteratively optimize their final design to choose the following parameters: fuel grain length port diameter throat diameter nozzle area ratio nozzle exit diameter Concept Design and Parametric Design The Hybrid Rocket Motor Design Project Final design drawings were generated for the combustion chamber and the supersonic nozzle using Solid Works. L dpdp dtdt dede
Fabrication The Hybrid Rocket Motor Design Project Combustion chambers were fabricated from aluminum round stock using manual lathes Supersonic nozzles were fabricated from graphite using a CNC turning center
Fuel Formulation The Hybrid Rocket Motor Design Project Hydroxyl Terminated Polybutadiene (HTPB) was formulated, mixed with aluminum particles and cured. Other fuels such as PMMA, HDPE and UHMW were machined from solid round stock
Mass flow rate was measured and controlled using a Teledyne Hastings HFC203 Mass Flow Controller. Thrust was measured using an Omega LC load cell. Chamber pressure was measured using an Omega Pressure Transducer. Development of the Hybrid Rocket Motor Test Stand The Hybrid Rocket Motor Design Project The Objective: Deliver a hybrid rocket motor test stand capable of measuring thrust (0-10 lb), chamber pressure (0-250 psig), oxygen mass flow rate (0-500 SLPM) The Team: Two senior mechanical engineering students, one junior mechanical engineering student and one senior electrical engineering student. The ignition system consists of dual automotive spark plugs which are energized using an ETP 300ST solid state induction coil
Development of the Hybrid Rocket Motor Test Stand The Hybrid Rocket Motor Design Project Igniters Pressure Transducer Flow Controller Solenoid Valve Check Valve
Development of the Hybrid Rocket Motor Test Stand The Hybrid Rocket Motor Design Project Load Cell Linear Bearing
Data Acquisition The Hybrid Rocket Motor Design Project Data acquired included: instantaneous chamber pressure, thrust, oxygen mass flow rate and high speed dynamic chamber pressure The data were acquired using an Agilent 34970A Data Acquisition Unit with GPIB interface and an HP 54645D digital storage oscilloscope With these data, each team was able to measure specific impulse (I sp ), characteristic exhaust velocity (C*) and thrust coefficient (C F ) and compare these measurements to their analytical models.
Is this valve open? …first test firing of the Hybrid Rocket Motor Test stand. The Hybrid Rocket Motor Design Project
Test Firing (HTPB/AL/GOX) The Hybrid Rocket Motor Design Project
Experimental Results The Hybrid Rocket Motor Design Project The analytical models reproduced the experimental data reasonably well. When the variation in actual oxygen mass flow rate was taken into account, analytical results matched the experiments very well!
Conclusions The Hybrid Rocket Motor Design Project At the beginning of the semester, students showed very little awareness of the space program and its significance (both historic and contemporary). This condition is surprising to the generation who grew up wanting to be astronauts. The hybrid rocket design project was successful in introducing a new generation of students to rocket science. The hybrid rocket motors were inexpensive, relatively easy to build and safe. The hybrid rocket motor test stand was an effective junior/senior level design project. Total project cost was approximately $2000. The test stand is now being used for scholarly pursuits.