Problem: A bellows pressure relief (PR) valve needs to be sized in terms of the mass flow rate for a gas pipeline with natural gas under critical flow conditions, i.e., when total superimposed plus built-up back pressure is equal to or less than the critical flow pressure.

The engineer first needs to locate a formula to determine the flow rate, and combine it with the known information on the inlet parameters for the valve.:

The flange inlet pressure at relieving conditions: 3000 psia
The inlet temperature at relieving conditions: 150ºF
Effective Orifice diameter: 1″ (25.4 mm)

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Ecouterre.com has a story on scientists from MIT who have synthesized a fiber that is capable of hearing, singing and generating electricty!

GreenAnswers.com takes a look at the famous five second rule, and deems it unsafe.

The box office succes of the movie Inception has led MSNBC.com to take an inside look into The Real Science of Dream Research.

And finally, in a story thousands of years in the making, scientists have determined that the Chicken came first. The Egg was unavailable for comment.

What’s orange and sounds like “a parrot?” -  A CARROT!

Why couldn’t the pirate go see the movie? – Because it was rated ARRRRRRRR.

Some jokes just get less and less funny the longer they are around. Now don’t get me wrong, I love a good “That’s what she said”, but it’s fading fast. There was a time when a simple utterance of the phrase provoked scores of laughter, regardless of whether or not it made any sense. Now I have to be careful to judge when and where I use it. Here’s another classic:

“Let’s extend shuttle flights!”

I realize I may be beating a dead horse here, but there are still people in the government pushing to add on more flights! (I’m looking at you Senator Nelson) Far be it for me to tell a senator what to think, but if you need any more proof that it’s time to let the sweet old Space Shuttle here’s a few facts.

ET’s gone and he ain’t coming back.

Lockheed Martian finished their very last external fuel tank a few days ago. This means that within weeks doors will be closed and lights shut off on a plant that was busy building tanks for over 30 years. Without these tanks, the shuttle would burn through it’s on board fuel supply in seconds and never make it to orbit.

One might argue that a quick injection of cash would get these people working again, however after talking with a few well placed sources; no amount of money will get this plant running any time soon. You see, all the tool and machines that they used to build these tanks have either been scrapped, destroyed, or repurposed. This by itself is probably the biggest reason NASA won’t/can’t add any extra flights.

SRBs

The solid rocket boosters (SRB) which give lift to the external tank: another component without which no shuttle mission will happen. While one company that makes the SRBs is eager to build more, a chat with several suppliers feel differently. SRB’s use technology and materials 50+ years old, which are still effective, but almost impossible to produce. Suppliers simply are not interested in providing the materials, like asbestos, to build SRBs. Many manufacturers have been relying on materials they stockpiled several years ago.

Even if the call went out tomorrow, there simply isn’t material available to answer that call.

I could go on about how independent analysts have determined that any additional launches would raise the risk of an accident 30% based on the age of the Space Shuttle, and that no facility exists to build more, but I hope I’ve made my point. The shuttle era is gone, let’s not make ourselves look like fools by trying to keep it around.

That’s what she… ahhhh nevermind.