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### Re: IRC

Posted: Tue May 16, 2017 11:01 am
As Dino and CF said! I have an example that may (or may not) clarify a little more from an engineering perspective. This is an effortpost, my apologies!!

In engineering analysis we often do a 'control volume analysis'. This means we take a process (say, an expansion at constant entropy, as in an ideal turbine), and model it with a diagram that kind of treats the process as a black box.

Here's an example of a turbine in control volume analysis. The fluid is processed by the turbine inside the dashed border. The space inside that border is the control volume (CV), and the borders themselves are called control surfaces (CS). The whole thing looks nothing like a turbine but that's ok, we're trying to understand what's going in to the CV, what's coming out, and how it's all related to one another without caring too much about the geometry of the whole thing. On the left, a fluid enters the turbine (through the left CS). This fluid has thermodynamic properties, which I label p_in (pressure), v_in (specific volume, which is like inverse density), and T_in, temperature. It will also have an entropy content s_in, and enthalpy h_in, which I haven't labeled. The m_in with a dot on top is the flow rate (mass-per-second) of the fluid.

On the right, this fluid exits the turbine with the same properties, subscripted _out. Something happens to the fluid inside the turbine (i.e. inside the CV). In fact, typically our incoming properties are for a high-temperature, high-pressure (etc) fluid, and in the turbine we extract this energy so that the outgoing properties are low-temperature, low-pressure. As we process that fluid inside the CV, we extract energy. More precisely, we say that the fluid does work on the turbine blades inside the CV. Intuitively, the high-energy fluid "pushes" on the blades, turning a shaft the blades are attached to, and that shaft leads outside the CV. We label this whole action by the W_out (with a dot on top): that is, the work done by the fluid on the turbine. The work is not a property of the fluid or the turbine, it happens between the fluid and the turbine. In our simplified representation of the turbine, this looks like work done at the boundary of the turbine, or at the boundary of our system. As this work is done by the fluid, its properties (T, v, p etc) will change because, having done the work, it has lost energy.

Also, because the turbine is not perfectly thermally insulated from its surroundings, and the turbine interior is at a higher temperature than its surroundings, there may be some heat loss at the control surface. The heat loss represents an energy transfer from the fluid inside the turbine to its surroundings. Because the fluid inside the turbine lost this energy, its properties (T, v, p etc) will change. The properties of the surroundings will also change. But the heat loss is the "agent" that does this, and it happens at the boundary of the system.

(I'll just add as a side note that the flow rate out m_out(dot) must be the same as the flow-rate in because of a condition we call "continuity", or conservation of mass. This just means that assuming our turbine doesn't accumulate fluid over time, then the stuff coming out must equal the stuff coming in.)

---------------------

So when you read an article that talks about 'heat content of the oceans', what it really is talking about is the amount of heat that's been absorbed by the oceans, and the increased energy that the oceans have because of this heat transfer. The energy content of a fluid may change... but it will do so by either heat transfer at its boundaries (e.g. the ocean surface, ocean floor), or by doing work or having work done on it. This is actually the expression of the first law of thermodynamics: the energy content of a system must be accounted for by (a) how much that content changes inside the system, and (b) how much energy is gained and lost at its boundaries. That gain and loss is expressed by work or heat.

### Re: IRC

Posted: Tue May 16, 2017 3:18 pm
Oooh! I had a control engineering class, but we mostly worked with 2-point and 3-point controllers, PID-controllers and fuzzy controllers.

Thank you very much for this great explanation! I think I got the concept now.

### Re: IRC

Posted: Wed May 17, 2017 12:47 pm
cheersbro

### Re: IRC

Posted: Thu May 18, 2017 2:55 am
Scytale wrote:cheersbro

### Re: IRC

Posted: Thu May 18, 2017 5:22 am
So, where is this whole irc stuff happening?

Can I have the address and all that for my phone app?

### Re: IRC

Posted: Thu May 18, 2017 5:23 am
server: irc.gamesurge.net
channel: #limittheory

### Re: IRC

Posted: Thu May 18, 2017 2:23 pm
Pamelrabo wrote:So, where is this whole irc stuff happening?

Can I have the address and all that for my phone app?
Dinosawer wrote:server: irc.gamesurge.net
channel: #limittheory
Hmm...a new recruit? The second today?

Wait, no. Cross that out. They both wrote here before.

### Re: IRC

Posted: Thu Jun 15, 2017 8:31 pm
<Talvieno> look what josh did http://i.imgur.com/aQZjMuX.png
* Detviet has no imgur HALP
<Detviet> SILVER
<Detviet> DO THE JEWTHING
<Talvieno> too late det
<Detviet> THE JEWTHING
<Talvieno> !muhaha
<Detviet> JEW IT NOW :V
<Saoirse> ψ(｀∇´)ψ
<Detviet> !cry
<Saoirse> ｡･ﾟﾟ･(>д<)･ﾟﾟ･｡
<Detviet> !tears
<Detviet> !halp
<Detviet> !waah
<Silver> huh?
<Silver> :V
<Detviet> YOU JEWMGUR REJEWER
<Silver> C Taiya
<Silver> oh
<Silver> OH
<Detviet>
<Talvieno> xD
<Talvieno> lol
<Talvieno> xD
<Detviet> Jew up, silver >.>
<Silver> today I try purgatory stuff
<Talvieno> that reminds me of the troll under the bridge in witcher 2
<Detviet> JEWGATORY
* narwhalz0111 regrets waiting so long before joining IRC.
<Talvieno> "gotsta drink"
<narwhalz0111> You crazy bastards.
<Talvieno> lol narwhalz You missed a LOT xD but there's plenty more in the future
<Talvieno> (yeah, like I was going to be nice and say "it's okay, you didn't miss much")
<narwhalz0111> Don't know how the snippets from the IRC thread failed to convince me long ago.
<Detviet>
<Detviet> well
<Talvieno> "Man, those guys are totally nuts"
<Talvieno> "Better stay away from there, yup"
<Detviet> now YOU can make those snippets

### Re: IRC

Posted: Thu Jun 15, 2017 9:14 pm
Our IRC is certainly an entertaining place to hang out at. I've had some very good discussions there as well.

### Re: IRC

Posted: Sat Jun 17, 2017 1:22 pm
BFett wrote:
Thu Jun 15, 2017 9:14 pm
Our IRC is certainly an entertaining place to hang out at. I've had some very good discussions there as well.
These are both true statements. I can agree on them.

### Re: IRC

Posted: Mon Jul 24, 2017 1:00 pm
I have no idea where else to put this, but:

A list of all Taiya's IRC quotes (stays up to date)

Earliest is September 13th, 2015.

### Re: IRC

Posted: Mon Jul 24, 2017 1:13 pm
IRC is the place to be.

### Re: IRC

Posted: Mon Jul 24, 2017 8:08 pm
ROFLMAO - Oh, I had some real doozies back then
Quote 196: <formalmoss> ooh cornie - you know we can't talk on a public channel like that ~~ added by Cha0zz on Oct 14 2015
Quote 197: <dwmagus> real article - http://www.ktuu.com/news/news/naked-wom ... t/35830756 <formalmoss> maybe she wanted to be the bun in someone's sandwich? ~~ added by Talvieno on Oct 14 2015
Quote 198: <formalmoss> ooh *giggle* you are so bad, magus ~~ added by Talvieno on Oct 14 2015
Quote 200: <formalmoss> diarrheoia is hereditary, it runs in your jeans. ~~ added by Talvieno on Oct 14 2015

### Re: IRC

Posted: Sun Jul 30, 2017 1:24 pm
My next piece of the project in getting Taiya's stuff online is her userdata.

http://talvieno.com/Taiya/userlist.php

It's very much a work-in-progress page, but I've got a lot of stuff running so far. It's not quite "real time", but it updates once every five minutes, so it should stay pretty well updated. I'm putting it aside for now, though, because I have many other things that need my attention. In the meantime, it's at least functional.

edit: It is now sortable and reverse-sortable by User ID Number, Name, Call, Nick count, Fondness, and Last Seen. That was slightly trickier than expected. Can't figure out how to make it upload ASCII characters properly, but I suppose that'll come eventually, and it's not that important anyway.

### Re: IRC

Posted: Wed Aug 02, 2017 9:26 pm
Goatbot is getting new stuff added to him too.

Code: Select all

15:25 < Goatbot> On the left we have Bob, male Gnome. He is Fit, Able, Watchful, Brisk, Helthy, Durable, Bright, Blessed.
15:25 < Goatbot> On the right we have Alice, female Gnome. She is Fit, Clumsy, Alert, Brisk, Well, Vulnerable, Bright, Unfortunate.
15:25 < Goatbot> Alice swings her cracked club at Bob, but is blocked
15:25 < Goatbot> Bob swings his shoddy sword at Alice hitting her right arm, viciously tearing the skin, savagely tearing the muscle, and badly tearing the bone
15:25 < Goatbot> Alice swings her cracked club at Bob, and is dodged
15:25 < Goatbot> Alice bleeds to death

Code: Select all

15:26 < Goatbot> On the left we have Bob, male Gnome. He is Weak, Able, Alert, Brisk, Infirm, Durable, Uncomprehending, Favored.
15:26 < Goatbot> On the right we have Alice, female Gnome. She is Fit, Bumbling, Watchful, Slow, Well, Fragile, Dull, Favored.
15:26 < Goatbot> Bob swings his old knife at Alice, but just misses
15:26 < Goatbot> Alice swings her good sword at Bob hitting his lower torso, cruelly tearing the skin, badly tearing the muscle, gently cutting the lower
spine, and killing Bob

Code: Select all

15:26 < Goatbot> On the left we have Bob, male Gnome. He is Fit, Nimble, Inattentive, Brisk, Frail, Durable, Dull, Favored.
15:26 < Goatbot> On the right we have Alice, female Gnome. She is Puny, Able, Watchful, Slow, Infirm, Durable, Dull, Favored.
15:26 < Goatbot> Bob swings his crude sword at Alice hitting her right leg, badly tearing the skin, gravely tearing the muscle, and gently cutting the bone
15:26 < Goatbot> Alice swings her crude knife at Bob, but is blocked
15:26 < Goatbot> Bob swings his crude sword at Alice hitting her upper torso, badly tearing the skin, and gently tearing the muscle
15:26 < Goatbot> Alice bleeds to death