Safety Procedures and Assessment Report For

Project METEOR Senior Design Team #06006

Team Members:

David Dale – ME (Project Manager) John Chambers – ME Brad Addona – ME

Jessica LaFond – ME Chris Hibbard – ME

Anthony Fanitzi – ME Jeff Nielsen – ME Dan Craig – ME

Faculty Mentors

Dr. Dorin Patru

Dr. Jeffrey Kozak

Faculty Advisor

Dr. Alan Nye

1.) Introduction: The purpose of this safety report is to outline and document all potential safety concerns and how they will be solved to statically test a hybrid rocket engine. This test will complete the main objective of the design team’s senior project. 2.) System Description 2.1 Purpose and Intended Use

The purpose of this system is to have a location and test setup that may be used multiple times by different senior design groups to test multiple rocket engines. It is expected that the test stand will be used less than 10 times per year.

2.2 System Development Through research, brainstorming, Pugh analysis and discussions with

professors the members of this senior design team (hereafter referred to as Team) believe that the current test setup is the best for our purposes based on ease of safety, construction, cost and data acquisition.

2.3 System components Refer to Appendix A: “System Components” 2.4 Functional Diagrams / Sketches / Schematics Refer to Appendix B: “System Diagrams” 3.) System Operations 3.1 Operating, Testing and Maintaining Procedures

Refer to Appendix C: “Operating, Testing and Maintaining Procedures” and Attachment 1: “Check-off sheet”

3.2 Special Safety Procedures

All safety issues will be controlled with the measures outlined in section 3.1. In addition there will be two fire-extinguishers (1 H20, 1 C02) on hand. Also, one of our team members is a volunteer Fireman and his expertise will be used if necessary. Future teams will have a volunteer fireman onsite during every testing.

3.3 Operating Environments The expected operating environment is a location with a large open area

(50’ x 100’) so it can be assured no bystander will be harmed in anyway. Ideal weather conditions are low wind, during daylight hours and no precipitation.

3.4 Facility Requirements or Support Equipment We will have a concrete bunker (7’ x 7’ x 13’ long) with 6” concrete walls to house our test stand in. The rear of the bunker will be open to allow the exhaust to exit. As a note, due to the thickness of the concrete walls, the

bunker can withstand a pressure force of over 7,000 psi. A van or pickup truck will be needed to transport the test stand, rocket engine, fuels, instrumentation, safety measures (shields, deflectors, fire extinguisher), and needed computers to the test site.

4.) Systems Safety Engineering 4.1 Ranking Hazardous Conditions Description Category Environmental, Safety, Health Results

Catastrophic I Could result in death, permanent total disability, loss exceeding $1M, or irreversible severe environmental damage that violates law or regulation.

Critical II

Could result in permanent partial disability, injuries or occupational illness that may result in hospitalization of operators, loss exceeding $200K but less than $1M, or reversible environmental damage causing a violation of law or regulation

Marginal III

Could result in injury or occupational illness resulting in one or more lost work days, loss exceeding $10K but less than $200K, or mitigatible environmental damage without violation of law or regulation where restoration activities can be accomplished.

Negligible IV Could result in injury or illness not resulting in a lost work day, loss exceeding $2K but less than $10K, or minimal environmental damage not violating law or regulation

4.2 Ranking Hazard probabilities Description Level Occurrence

Frequent A Continuously experienced Probable B Occurs frequently

Occasional C Will occur several times Remote D Unlikely, but can be expected to occur

Improbable E Unlikely to occur, but possible 4.3 Identifying Hazardous Conditions 4.3.1 List of all hazards Refer to Appendix D: “Hazards”

4.4 Hazardous Materials Refer to Appendix E: “Hazardous Material”

5.) Conclusions and Recommendations 5.1 Results

The conclusion of this safety assessment is that there are risks involved with the testing of a hybrid rocket, but the risks can be mitigated through the initial and redundant safety measures taken by the project design team. The risks can be reduced enough that we can confidently test a hybrid

rocket without putting the members of our team, the environment or a third party in danger.

5.2 Stress Analysis Refer to Appendix F: “Stress Analysis of Critical Components”

APPENDIX A

System Components

1. Concrete Bunker

2. Anchor Bolts

3. Ground (Flat) Plate

4. Leveling feet

5. Slide Stop

6. Rails

7. Linear Bearings

8. Rail ties

9. Pillowblocks

10. Rocket Engine Assembly

11. Pulleys for Load Cell calibration

12. Cable for Load Cell calibration

13. Oxidizer delivery system

14. Sensors / Load Cell

15. DAQ Computer

16. Exhaust deflector

17. 10’ Hose

18. Ignition System

19. Nitrous Oxide Tank / Nitrogen Tank

20. 2 Fire extinguishers (1 CO2, 1 H20)

21. Video Camera

22. Generator

23. Power Supply

24. Ear Plugs

25. Safety glasses

26. First Aid Kit

27. Tools (socket set, wrenches)

APPENDIX B

System Diagrams

APPENDIX C

Operating, Testing and Maintaining Procedures

Setup Procedure We will be able to house the test stand in the concrete bunker when not in use as the

bunker will have locking steel doors on it. So, all of the test stand besides the rocket

engine assembly will be set up once and not taken down.

Secure Test Chamber

1. Ensure bearings are free to move and do not bind

2. Put engine assembly in pillowblocks, tighten bolts to a minimum 7 lb-in

3. Level ground plate

Connect Data Acquisition / Test Electronics

4. Connect thermocouples, pressure sensors and strain gauges to rocket, run wires to

DAQ computer

5. Test / Calibrate all gauges

6. Turn on and off inline valves for each tank to ensure successful operation

7. Connect 10’ Hose to the Injector on the Rocket Engine Assembly

Clear Area

8. Walk perimeter and make sure there is no one in the area that is not with the team

9. Remove any flammable debris that may be around test location

10. Connect 10’ hose to the tanks feed system

11. Connect ignition system to power supply

12. Team members will then be positioned behind barriers to ensure their safety and the test will begin.

Setup Checklist

Action Completed Initial Concrete pad inspected for cracks or crumbling All Anchor Bolts installed securing feet to concrete All Anchor Bolts tightened to at or above required torque Place flat plate on feet and tighten down after leveling Tighten Pillow Block to Slider Rails with required torque Ensure each pillow block is attached to proper rail put in order Rocket engine body checked for cracks or fatigue Ensure all bolts are tightened properly into injector plate Place Rocket in pillow block and tighten blocks to required torque Ensure rocket assembly slides properly on rails Ensure bolts for rail stop and tightened properly Mount load cell to rail stop in correct orientation Ensure bolts are properly tightened in pulley calibration stands Attach rigid link from rocket to load cell Attach cable to calibration eye hook and apply 200 lb calibration force Install sensors Test sensors to make sure they work and are calibrated Test electronic control valves on all tanks Remove calibration cable and weights Attach feed system hose to rocket (other end not connected to tanks) Test remote computers to ensure they are collecting data Set up thrust deflector 18” away from edge of lexan Clear perimeter of any bystanders / debris Attach electric leads to igniter Team located behind barrier and ready to fire

Test Procedure

Countdown

t = 0 Apply current to igniter, start DAQ

t = 0.5 turn on N2O

t = 1 Turn off current to igniter

1 < t < test time Pure N2O

t = test time Electronically shut off N2O, turn on N2 Purge

t = test time + 3 Electronically shut off N2, stop DAQ

1. Visually inspect rocket before approaching to ensure flame has extinguished

2. Manually shut off redundant valves on tanks

3. Remove outer hoses

4. Safely remove Engine Assembly

APPENDIX D Hazards

Hazard / Mishap Category Level Control Residual

Risks Anchor bolts may not hold in concrete

III D There will be multiple, redundant, bolts in the concrete, more than one would have to fail for this to be a risk

None

N2O tanks explode

I D Tanks will be separated from observers by concrete bunker

None

Pillowblocks are not tightened properly

III C This will be checked in our pre-test inspection, also there will be multiple blocks

None

Rocket explodes due to excess pressure

I E There will be a pressure relief valve on the rocket engine and the bunker will house all shrapnel

Shrapnel

Exhaust ignites surroundings

II D There will be an exhaust deflector and we will be cognizant of what is behind the test stand, making sure there is nothing flammable within a reasonable distance. There will also be fire extinguishers on hand

Small fire

Injector plate separates from rocket body

II D The pillowblocks will hold the chamber, the lip on the front pillowblock will stop the injector plate

None

Hazard / Mishap Category Level Control Residual

Risks Chunks of fuel are spit out from rocket

III C If anything solid is spit out from the nozzle, it will first hit the deflector, breaking it up and then fall harmlessly to the open area behind the rocket

Debris contacts observer or small fire

Nozzle disengages from rocket during firing

II D The nozzle will be moving away from any observer or bystander and will strike the deflector plate then falling harmlessly to the ground

Debris fly forward and contact observer

Valve for any tank is stuck open

IV D No harm in this, except we cannot stop the test, we have to wait for the rocket to burn itself out

None

Hoses burst or become unattached

III D If the hoses become unattached the rocket will simply stop, the burst will be contained within the concrete bunker

None

Foreign object enters test stand

IV C The test stand will be enclosed on 5 of 6 sides, if an object enters the test stand it could harm the object (if living) but will not be detrimental to the test or any observers

None

APPENDIX E

Hazardous Materials 1. Nitrous Oxide, N2O 2. Nitrogen, N2 3. Hydroxyl Terminated Poly-Butadiene (HTPB – tire rubber) 4. Pyrogen / NC Laquer (part of ignition system) 5. Ammonium Perchlorate (part of ignition system)

See attached *.pdf files for their MSDS.

APPENDIX F Stress Analysis of Critical Components

Pillow Block Analysis Two different aspects were taken into account when analyzing the pillow blocks for this test set up. First being the bolts that connect the blocks to the rail ties. Second being the torque required in order to provide enough friction to hold our rocket stationary with our expect thrust of 200 lbs. Shigley’s Mechanical Engineering Design 7th edition was referred to in all of our bolt calculations and tables used to ensure the grade of bolt we were selecting was appropriate. For our actual test stand we are using only Grade 8 bolts which are above the required strengths found in our calculations. Concrete Anchor Bolts The anchor bolts hold the whole test stand to the ground. We must be sure they hold. The concrete will fail long before the actual bolts will fail (~120,000psi for bolts, ~2900psi for concrete), so calculations must be done to determine how much force the concrete can handle. As long as the anchor bolts are embedded at least 2.375” into the concrete the bolts will have a factor of safety over 40. The torque equation was again used to find out how much torque should be applied to the bolts during the setup process.

Feet Analysis The foot bolt analysis is similar to the one completed for our pillow block bolts. However, it is important to note that our calculations are for only one foot taking up all the force generated by our rocket when in actuality we have 8 feet in place to take up the load. Pressurized Cylinder (Combustion Chamber) The tangential stress was found to be the maximum stress experienced by the cylinder. A concentration factor for a pressurized cylinder with one hole in it was used for our calculations. Since there are two holes in our cylinder, we combined them into one larger hole, this is an acceptable assumption. Using Peterson’s Stress Concentration Factors a factor of safety of 4 was found for the cylinder, using 304 Stainless Steel. It is also important to note that if the pressure inside our cylinder did for some reason increase to above 1000 psi, that all flow of Oxidizer would halt and this would in turn prevent any possibility of our tank bursting. Injector Plate Bolts These bolts were sized in the exact same manor as the bolts in the previous paragraph “Bolt Analysis”. Using a factor of safety of 2 the pre-load was set to the expected force, a proof load and proof strength was found from this value and bolts were chosen from Table 8-9 in the Mechanical Engineering Design textbook (Shigley, 7th ed.). The required torque on the bolts was also calculated.