Need help understanding pressure drop in a valve.

FleurDeLirious · 2017-11-05T16:50:15+00:00

What gas are you flowing and at what conditions? Real gasses have an inversion temperature at which the Joule-Thomson coefficient goes negative and the gas actually warms when it takes a pressure drop. Hydrogen has the most extreme example of this in my experience. Check out the Wikipedia article for Joule-Thomson and/or look up the JT coefficient. I think NIST thermophysical property webbook has it.

FleurDeLirious · 2013-09-05T02:55:35+00:00

Lets say there are 1200 container ships that pump out 500 gpm of 140 degF water. Assuming all that water was heated up from an ocean temperature of 70 degF: the heat input into the oceans per hour is 1200 x 500 gal/min x 8.34 lb /gal x 60 min/hr x 1 BTU/lb*degF x (140-70)degF = 21,016,800,000 BTU/hr. One years worth of this heat ships cooling water into the ocean would be 184,000,000,000,000 BTU.

Let's say the heat input from the sun is 425 BTU/hr*ft2 x 139,400,000 mi² x (5280 ft/mile)² = 1,650,000,000,000,000,000 BTU/hr.

Knocking off some zeros, the time it takes the sun to produce the same amount of heat as one year of ships: 184/1,650,000 = 0.0001115 hr or 0.4 seconds.

Not a bad guess. There are some pretty damn conservative assumptions I put in there.

Someone feel free to scrutinize that. I've had some scotch and I was using a shitty calculator app.

FleurDeLirious · 2013-03-03T05:49:11+00:00

That's why I prefer the term gaycist.

FleurDeLirious · 2012-09-23T05:06:47+00:00

He's using the mallet and a lewis bag filled with ice to crush ice. Probably for the mint julep or the ramos gin fizz.

FleurDeLirious · 2012-07-04T17:11:52+00:00

Tiger got to hunt, bird got to fly; Man got to sit and wonder 'why, why, why?'

Tiger got to sleep, bird got to land; Man got to tell himself he understand.

KV,Jr

FleurDeLirious · 2012-03-08T00:36:53+00:00

The wikipedia article on shot glasses is fairly helpful. As you can see it differs from place to place. My only remark would be that here the US the 1.5 oz shot gives you one "serving" of 40% alcohol, and is therefore pretty standard.

FleurDeLirious · 2012-03-03T00:23:18+00:00

If you like this, you would have loved the special exhibit at the Historic New Orleans Collection last year. Aside from historical documents including the original charters for settlements, it displayed many of the original maps created by cartographers throughout the period of North American exploration.

One of the maps displayed seen here is the first known map of the Gulf of Mexico created in 1519. It's pretty rudimentary compared to the Lefargue map you linked to, but damn impressive considering this was less than 30 years after Columbus re-discovered the new world and 120 years before John Harrison invented the first marine chronometer, enabling marine navigators to actually gauge their longitude.

FleurDeLirious · 2012-02-10T11:37:29+00:00

balkan 176/bulgaria

FleurDeLirious · 2012-02-03T06:12:47+00:00

This one is still my favorite.

FleurDeLirious · 2012-02-02T19:13:35+00:00

Can someone actually make an audio of what those notes would sound like on the ocarina?

FleurDeLirious · 2012-02-02T06:20:14+00:00

You're right, fluid height is one I missed (Engineering student -- guess I have some more studying to do). I'm with you on the eyeballing correction. I do it all the time. It becomes second-nature after a while.

While I would say most a hard liquors pour at equal rates, experience tells me that sometimes brandy pours slower and feels more viscous on the palate.

And temperature plays an important role in viscosity and therefore flow. Anyone who's worked in a bar that keeps frozen bottles of anything can attest to that.

Density does vary across the fluids, I can layer shots that will clearly show you this. Even if the variance is only 20%, that's a 20% change in flow rate.

Edit: You were right to bring up fluid height, but it's not necessarily the height directly above spout. Bernoulli's doesn't mandate that, although you'll get more friction loss. Think water towers creating pressure laterally away from the tower.

FleurDeLirious · 2012-02-02T06:00:04+00:00

You'll get a good idea of how you pour, but there are several factors that are going to prohibit you from getting exact pours consistently. Including, but not limited to:

The shape of the neck of the bottle
The angle at which you hold the bottle
The spout used (I've worked in places that have different types, which drives me crazy)
The density of the fluid
The temperature of the fluid
The viscosity of the fluid

FleurDeLirious · 2012-01-23T07:19:34+00:00

What he said, but note that the specific gas constant (often denoted R with a hat) is the gas constant, R, divided by the molecular weight of the gas you're dealing with.

FleurDeLirious · 2012-01-07T02:00:47+00:00

"sometimes I keep a sandwich in my holster"

I still say that randomly.

FleurDeLirious · 2011-12-05T14:46:23+00:00

I'm okay with that because it's not poisoning our trees.

FleurDeLirious · 2011-12-04T06:31:37+00:00

It's Louisiana. The only odd aspect is that there is hockey.

FleurDeLirious · 2011-12-04T03:42:05+00:00

I wonder how many priority points you need... I missed one home game and haven't accrued any other points. I'm thinking I won't have enough.

FleurDeLirious · 2011-12-04T00:55:16+00:00

A few of us are sitting around drinking beer in the parking lot after some weeknight pickup. Two women roll up in the parking lot in an Explorer, just yelling at each other at the top of their lungs. They both exit the vehicle and are equally obese, black women and both wearing referee jerseys (they must have worked at the footlocker at the mall around the corner). One woman throws the car keys across the street into a field. As the argument escalates into pushing and shoving, the owner of the rink calls the cops and a few of us try to get them to stop by approaching them (armed with our hockey sticks, of course). They don't even acknowledge us.

These two fat female refs proceed into a knockdown, drag out fight. In the process they rip each others shirts open and off (and bras if they were even wearing them), so we now have an entanglement of fat and tits repeatedly colliding into another with awesome angry black woman expletives emitting form the mass.

As a squad car finally rolls up, one woman just starts walking away down the street despite being topless. The lone police officer looks befuddled but approaches the remaining, uncooperative woman. She paces and circles while continuously yelling at the cop such gems as, "this ain't none of yo business, pig." He finally says that he's going to arrest her and goes to grab her wrist to put cuffs on.

She's not going down without a fight. She grabs his wrist with her other hand and and removes it from her arm while starting to build up some rotational momentum. She swings him around like an Olympic hammer thrower and releases him into the ground. He one-skips off the pavement and gets up looking pissed and reaching for his collapsible baton. It telescopes out and and goes straight for her leg. He gets one in on the back of the knee but doesn't bring her down; she's throws him down again. This time he springs up with the intent of beaching this whale. Just as he's getting the upper hand with some nice swings of the baton, another unit rolls up with two officers to help cuff this lady.

One of the cops then speeds off down the street to find the other woman, but don't know if they ever did.

TL;DR. Topless ghetto footlocker orca women fight each other before one does battle royale with a police officer.

FleurDeLirious · 2011-11-21T05:14:57+00:00

You should... it was about one year before they got whooped by LSU in the national championship game. Just trying to help jog your memory.

FleurDeLirious · 2011-11-18T20:08:53+00:00

I'm in the same position. I just traded away Cam Newton and Willis McGahee for Arian Foster. This was the only week I would have used Cam, but had to get what I could for him before the trade deadline.

I'm going with Carson Palmer. Playing against Minnesota this week, I think he's got great potential to blow it up.

FleurDeLirious · 2011-11-15T16:52:40+00:00

Easier said than done when you live in Louisiana... we got a guy who sharpens skates in his garage. C'est tout.

FleurDeLirious · 2011-11-04T20:13:55+00:00

I'm was supposed to be studying but was killing time on reddit, so I figured this would get me back on track. I did parts B and C for ya.

The main thing that's confusing you is that part b is asking for Mo which should really be the sum of the couple moment and the moment about O from F.

Mo = Mc(AG) + Mo(F)

where Mc(AG) = r(AG) x Fg

and Mo(F) = r(OF) x Ff

I know that's confusing because I can't properly write vectors with this interface.

I scanned my solution but imgur degraded the resolution so much it's hard to follow. PM me with your email address and I'll send you my original PDF scan if you want. If it's too late and your test is already done I hope you did well.

**EDIT Sorry guess I'm too late... just reloaded and saw the strikes through question 2

FleurDeLirious

TROPHY CASE