Testing a 100lbf Jet Engine: Blast Shields

[btbam91]

Hey guys. As the title reads, I am a part of a research project and we will soon be testing a 100lbf jet engine. We take safety very seriously and want to take all the proper precautions in order to ensure everybody involved will come out of the experimentafely in case something goes wrong.

With that said, I am aware that the safest thing you can do is to stand as far away as possible. A blast shield is not to be relied upon as the sole source of protection in case a jet engine explodes. At high a RPM, the amount of kinetic energy in those blades is fatal.

So I am asking for advice on building blast shields. From my limited research thus far, I see that some are made of Lexan: http://en.wikipedia.org/wiki/Lexan

Thank you everybody!

 

[AlephZero]

I wouldn't play around with Lexan. A couple of layers of sandbags completely surrounding the engine would probably be about right. (NOTE: THAT IS NOT TO BE TAKEN AS LEGAL ADVICE ON SAFETY!)

If you want to see what's going on inside the sandbags, small video cameras are cheap and expendable.

You can't easily contain anything that wants to come out of the front or back of the engine (e.g. because of a broken rotor or failed bearings) without messing up the air flow, but at least that debris will travel more or less in a straight line ... UNTIL IT HITS THE GROUND STILL SPINNING AT 50,000 RPM, and/or bits start falling off it while it is still in free flight.

In real life, you would want to spin the rotor(s) up to their design speed to check their integrity before you try running the engine under its own power. But remember the engine hasn't read your calcs on what its design speed ought to be, so it might have other ideas about how fast it wants to run...

 

[Enthalpy]

Sandbags, or dig a pit in the soil. Do NOT rely on a plastic.

 

[btbam91]

Thanks for the replies guys. You have definitely put some ideas into my head.