P07105: Project METEOR - Steel Rocket January 19, 2007 1 Project METEOR Design and Optimization of a Small Scale Rocket for Pico- Satellite Launching Team

January 19, 20071

P07105: Project METEOR - Steel Rocket

Project METEOR

Design and Optimization of a Small Scale Rocket for Pico-Satellite Launching

Team Members:Ray MulatoJoe D’AmatoJoel BaillargeonKent EtienneGuion LucasRyan Kuhns

January 19, 20072


Project Overview

Projected Flight Pattern

EARTH

BALLOON-PLATFORM-

ROCKET-SATELLITE

LAUNCH

~30

km

ROCKET-SATELLITE

LAUNCH

ROCKET-SATELLITE

LAUNCH

SATELLITE IN LOWEARTH ORBIT

SATELLITE IN LOWEARTH ORBIT

~16

0 k

m

LAUNCH PLATFORMLANDS W/ PARACHUTE

AND IS RECOVERED,REFURBISHED AND

REUSED

10-50 km10-70 km

BALLOON-PLATFORM-ROCKET-SATELLITE REACH ROCKETLAUNCH ALTITUDE AFTER

~1HOUR

PLATFORMSTABILIZATIONAND ROCKET-

SATELLITEORIENTATION

PLATFORMSTABILIZATIONAND ROCKET-

SATELLITEORIENTATION

Fig. 2. Typical Mission Profile

January 19, 20073


Hybrid Rocket

• Classified as utilizing a liquid oxidizer and solid propellant to achieve thrust

– Current Oxidizer: Nitrous Oxide (NOX)

– Current Propellant: Hydroxyl Terminated Poly-Butadiene (HTPB)

– Possible Propellant: Poly-Methyl Methacrylate (PMMA )

Project Overview

January 19, 20074


Injector Plate

Garolite Pre & Post Combustion Chambers

2-D Nozzle

Hydroxyl-Terminated Polybutadiene (HTPB) Fuel Grain

Chamber WallSnap Ring

Current Test Chamber Setup

January 19, 20075


• Theoretical Isp for HTPB & NOX 320 s

• Properties– Efficiency of propulsion system– Ratio of thrust to weight– Change in momentum per unit mass of propellant – Affected by combustion temp, chamber pressure, exit pressure, and

mass flow rate

gm

FI sp

0g

vI esp

Project Deliverable – Specific Impulse

January 19, 20076


• Optimization of:– Nozzle Geometry– Fuel Grain

• Material• Geometry

– Oxidizer Flow Rate – Ignition System

• Data Acquisition– Temperature– Pressure– Thrust

Specific Impulse of 220 s

Project Objectives

January 19, 20077


From Guidance Team for controlled flight to 90 km:mfuel = 10kg;

mdot = 0.2kg/s;

tburn = 50 s; T = 445 N (100 lb)

Specification Number

Design SpecificationUnit of

MeasureMarginal

ValueIdeal Value

1 Specific Impulse sec 227 300

2 Oxidizer/Fuel Ratio - 5 8

3 Thrust N 445 500

4 Burn Time sec 50 60

5 Overall Mass Flow Rate kg/s 0.2 0.17

6 Mass of Fuel Grain kg 1.6 1.1

7 Mass of Oxidizer kg 8 8.75

Project Specifications

January 19, 20078


Testing Purpose

• Testing took place December 9th & 10th, 2006

• Vary Nozzle Geometry to see the effects on thrust

• Conceivably measure mass flow rate of system– Weigh nitrous oxide tank and fuel grains prior and after each test– Come up with approximate O/F ratios

• Introduce Team to current design

January 19, 20079


Results

January 19, 200710


Testing 11 Degree Half Angle

January 19, 200711


Testing 11 Degree Half Angle

Pressure

-100.0000

0.0000

100.0000

200.0000

300.0000

400.0000

500.0000

600.0000

0.0000 5.0000 10.0000 15.0000

Time (s)

Pre

ssu

re (

psi

)

Tank

Pre-Comb

Pre-Inj

Thrust

0.0000

10.0000

20.0000

30.0000

40.0000

50.0000

60.0000

70.0000

80.0000

90.0000

0.0000 2.0000 4.0000 6.0000 8.0000 10.0000 12.0000 14.0000 16.0000

Time (s)

Th

rust

(lb

)

January 19, 200712


September 16th, 2006 Test

0 2 4 6 8 10 120

100

200

300

400

500

600

700

800

Time(s)

Pre

ssur

e (p

si)

Pressure

0 2 4 6 8 10 120

10

20

30

40

50

60

70

80

90

100

Time (s)

Thr

ust

Thrust

January 19, 200713


First Testing – December 2006

• Observations– Overall system setup– Ignition system can be inconsistent in terms

of time– Oxidizer tank temperature varied

considerably from test to test– Teflon tape in feed system was tedious and

led to increased time between tests– Brass fittings can be cross-threaded and/or

broken easily– Noticeable inaccuracies in current mass flow

rate measurement– Power supply was convoluted– 8 Degree Half Angle Nozzle design gave the

best thrust results– Nitrogen tank regulator was damaged,

consistently leaks, had to develop a work around for it

• Conclusions– Began to reduce time between tests– Steady voltage and current supply is needed

to minimize ignition time– A method of controlling internal tank

temperature is needed to remove guesswork– Stainless steel can be used in place of brass

and teflon combination– Stainless steel fittings in oxidizer feed system

should be used– Means of gathering reliable mass flow is

crucial – Coriolis flow meter or volumetric flow meter in combination with other values

– A generator might be a better means of running the operation

– Difficult to draw definite conclusion from this, as multiple variables play a role in thrust

– Need to order a more robust regulator

January 19, 200714


Feed System Equipment

• Goals of adding additional feed system equipment:– Acquire a reliable value for mass flowrate in order to calculate a number of

parameters• Regression rate• Test Chamber Pressure• Oxidizer-Fuel Ratio• Oxidizer Mass Velocity

– Feedback Pressure Regulator• Constant supply pressure leads to overall experimental control• Capability to vary supply pressure

– Optimization of nozzle for a supply pressure– Gas Tank Heating Blanket

• Allows for a controlled internal tank temperature– Temperature control leads to internal pressure control

January 19, 200715


• Longer, wider chamber for longer burn and increased thrust

• Injector plate – redesign hole pattern and sizing in order to increase burn efficiency and completeness

• Use of Polymethyl Methylacrylate (PMMA) as a solid fuel in place of HTPB – possibly higher thrust

• Redesign of Pre and Post combustion chambers to minimize viscous losses inside the chamber

• Redesign of nozzle to take advantage of expansion of hot gas inside the diverging section of the nozzle rather than behind it

• Redesign of fuel grain to optimize regression rate and thrust (increase surface area exposed to flame)

Possible Test Chamber Improvements

January 19, 200716


N2

N2O

2

4 25

22

21

14

26

2

1

22

6

3

6

2

22 25

6 3

7

6

6

6

12

15

10

15

14 28

8 26

2

26

2

11

2 18

2

19

2

17 17 17

16

23

1

4

26

2 20

19

18

9

2 22 25

14 6

Injector

Combustion Chamber

24

5

16

Lexan Frame

Hybrid Rocket Feed System

Current Feed System

January 19, 200717


• Control of Oxidizer (N2O) Pressure via tank as well as before injector – installation of a feedback regulator

• Use of Stainless Steel in place of Brass in Nitrous Oxide feed system due to N2O effect on brass components (shorter life, corrosion of surfaces)

• Use of a tank “stand” to hold oxidizer tank inverted as well as to measure weights (for the current round of testing)

Possible Feed System Improvements

January 19, 200718


N2

N2O

2

4 25

22

21

14

26

2

1

22

6

3

6

2

22 25

6 3

7

6

6

6

12

15

10

15

14 28

8 26

2

26

2

11

2 18

2

19

2

17 17 17

16

23

1

4

26

2 20

19

18

9

2 22 25

14

6

Injector

Combustion Chamber

24

5

16

Steel Baseplate

Hybrid Rocket Feed System

299999999

30

Highlighted areas show where changes are being made

Proposed Changes to Feed System

January 19, 200719


Feed System Equipment

Test Chamber

Pressure Transducer

Tee Fitting

Mass Flowrate Meter

Backflow Pressure Regulator

Inline Flow Filter

January 19, 200720


Design of Experiments

• Factorial Method vs. One Variable at a Time– Factorial method able to achieve comparable results

with fewer tests– Factorial method able to correlate relationships

between factors being tested

Factor A

Fac

tor

B

Low High

High

3

6

2

1

4

5

Factor A

Fac

tor

B

Low High

High

2

4

1

3

O.V.A.T. Factorial

January 19, 200721



• NOX Pressure (Pre-Inj.)• Length of Fuel Grain• Post-Combustion Chamber• Nozzle• Injector Plate• Fuel Grain Additive

• Fuel Grain Geometery

• 3 levels (∆ of 50 psi.)• 2 levels (11” – 18”)• 4 levels (1.5” - 3.0”; ∆ 0.5”)• 2 levels• 2 levels (4 holes/ 9 holes)• 2 levels (Alum. Pwdr/ Non-Alum.

Pwdr)• 3 levels (Star, Circle, Cross)

Independent Test Variables Levels

January 19, 200722



• Reasons for choosing these variables:– Short lead time for testing– See how pressure, and (L/D) ratio of the fuel grain effects thrust– No prior knowledge of injector plate design– Combustion chamber wasn’t chosen due to the additional changes to the system

needed to accommodate that test.

• NOX Pressure (Pre-Inj.)• Length of Fuel Grain• Injector Plate

Variables In Next Test

• 3 levels (∆ of 50 psi.)• 2 levels (11” – 18”)• 2 levels (4 holes/ 9 holes)

Levels

January 19, 200723


Senior Design I Project Plan

Documents

P07105: Project METEOR - Steel Rocket January 19, 2007 1 Project METEOR Design and Optimization of a Small Scale Rocket for Pico- Satellite Launching Team