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Thermodynamics of Hell Pages: 12

Karl Hofmann on Tue February 24, 2004 5:29 AM User is offlineView users profile

I pinched this one from Roger Goetsch who posts on www.Refrigeration-Engineer.com







Received the following from my brother:

The following is an actual question given on a University of Washington chemistry mid-term. The answer by one student was so "profound" that the professor shared it with colleagues, via the Internet, which is, of course, why we now have the pleasure of enjoying it as well.

Bonus Question:

Is Hell exothermic (gives off heat) or endothermic (absorbs heat)?

Most of the students wrote proofs of their beliefs using Boyle's Law (gas cools off when it expands and heats up when it is compressed) or some variant.

One student, however, wrote the following:

"First, we need to know how the mass of Hell is changing in time. So we need to know the rate that souls are moving into Hell and the rate they are leaving. I think that we can safely assume that once a soul gets to Hell, it will not leave.

Therefore, no souls are leaving.

As for how many souls are entering Hell, let's look at the different religions that exist in the world today. Most of these religions state
that if you are not a member of their religion, you will go to Hell.

Since there is more than one of these religions and since people do not belong to more than one religion, we can project that all souls go to
Hell. With birth and death rates as they are, we can expect the number of souls in Hell to increase exponentially.

Now, we look at the rate of change of the volume in Hell because Boyle's Law states that in order for the temperature and pressure in Hell to stay the same, the volume of Hell has to expand proportionately as souls are added. This gives two possibilities:

1) If Hell is expanding at a slower rate than the rate at which souls enter Hell, then the temperature and pressure in Hell will increase
until all Hell breaks loose.

2) If Hell is expanding at a rate faster than the increase of souls in Hell, then the temperature and pressure will drop until Hell freezes over.

So which is it?

If we accept the postulate given to me by Teresa during my Freshman year, "...that it will be a cold day in Hell before I sleep with you", and take into account the fact that I still have not succeeded in having an affair with her. Then #2 above cannot be true, and thus I am sure that Hell is exothermic and will not freeze over."

THIS STUDENT RECEIVED THE ONLY "A"



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Never knock on deaths door... Ring the doorbell and run away, death really hates that!

NickD on Tue February 24, 2004 9:17 AM User is offline

Superheat, isentropic efficiency, exothermic, endothermic, FOT, TXV, maybe this site needs an AC glossary of common AC terms with a brief definition.

I won't touch on the religous end, but a certain amount of truth is that if I don't believe as they do, I am going to hell.

TRB on Tue February 24, 2004 9:22 AM User is offlineView users profile

Quote
Originally posted by: NickD
Superheat, isentropic efficiency, exothermic, endothermic, FOT, TXV, maybe this site needs an AC glossary of common AC terms with a brief definition.

That would require an extra category and we know how you hate to use the scroll bars.

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When considering your next auto A/C purchase, please consider the site that supports you: ACkits.com
Contact: ACKits.com

Karl Hofmann on Tue February 24, 2004 9:38 AM User is offlineView users profile

LOL I recon that heaven is overrated, playing harps and floating round on clouds, being nice to folk sounds a bit dull to me.
Hell seems to be the place to be!

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Never knock on deaths door... Ring the doorbell and run away, death really hates that!

TRB on Tue February 24, 2004 9:40 AM User is offlineView users profile

Heck I live there and its not that hot!!!!

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When considering your next auto A/C purchase, please consider the site that supports you: ACkits.com
Contact: ACKits.com

MrBillPro on Tue February 24, 2004 9:51 AM User is offlineView users profile

Hey Karl, if Hell seems to be the place to be! You need to try and stay alive as long as you can because that is were we are now! of course that is just my opinion. How could death be any worse than were you are now even if you don't believe there is a Heaven, You don't have to work anymore, put up with you wife, no more children to raise, no more mortgage, never have to wonder what's for supper, I mean I could go on and on I personally believe there is a Heaven and for those who don't Death could be there Heaven.


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Don't take life seriously... Its not permanent.

Edited: Tue February 24, 2004 at 9:52 AM by MrBillPro

NickD on Tue February 24, 2004 9:59 AM User is offline

Automotive Air Conditioning Procedures and Tips could use a glossary thread, no need to start another topic.

Should be a golden opportunity for AC experts in hell, do you suppose you need a 609 certificate down there or wherever its at?

Do you suppose the EPA has complete control over refrigerants in hell? Gosh if they do, that would be hell. Probably why its so hot down there, or wherever hell is at.

TRB on Tue February 24, 2004 10:12 AM User is offlineView users profile

Well Nick if you create it I'll be glad to add it to the tips and procedures forum.

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

When considering your next auto A/C purchase, please consider the site that supports you: ACkits.com
Contact: ACKits.com

NickD on Tue February 24, 2004 10:35 AM User is offline

Here's a start:

ACCUMULATOR: A liquid vapor separator that stores and dries the refrigerant. It is located in the low pressure side between the evaporator and the compressor. Used on late model GM, Fords and Imports with the fixed orifice tube.
BLOWER FAN: A motor-driven fan used to force air through the evaporator or heater core and circulate air through the passenger compartment.

CLUTCH CYCLING SWITCH: A switch which uses evaporator core temperature or pressure to control electrical current to the compressor clutch field coil to prevent the evaporator core from freezing.

COMPRESSOR: Refrigeration pump that circulates refrigerant and increases the pressure of refrigerant vapor.

COMPRESSOR CLUTCH: An electro-magnetic coupling that connects or disconnects the belt driven compressor pulley to the compressor shaft.

CONDENSER: System component that removes heat from the refrigerant, changing it from a hot vapor to a warm liquid. It is usually located in the front of the vehicle's radiator.

CYCLING CLUTCH ORIFICE TUBE (CCOT): Designation for a system used by GM, Ford and some Imports that utilizes an accumulator and orifice tube instead of a receiver-drier and expansion valve. The system operates by using a thermostatic switch or a pressure sensing switch to cycle compressor operation.

CYCLING CLUTCH SYSTEM: A system which controls evaporator temperature by turning the compressor on and off with a clutch cycling switch.

DESICCANT: A drying agent used in refrigeration systems to remove excess moisture (molecular sieve or similar substance).

DISCHARGE LINE: Connects the compressor outlet to the condenser inlet.

EVAPORATOR: System component that removes heat from the air entering the passenger compartment. The refrigerant enters as a low pressure liquid, and leaves as a low pressure vapor. It is located near the vehicle cowl.
EXPANSION VALVE: See "THERMOSTATIC EXPANSION VALVE"

HIGH PRESSURE CUT OFF SWITCH: Found mainly on FWD vehicles, this switch will disengage the compressor clutch when excessive discharge pressure is sensed.

LIQUID LINE: Refrigerant line connecting the condenser outlet to the evaporator inlet.

LOW PRESSURE CUT-OUT SWITCH: Located either in the high pressure or low pressure side of the system, it disengages the compressor clutch when system pressure drops below a predetermined valve.

RECEIVER-DRIER: A canister that contains a desiccant to remove moisture and is used to store and filter liquid refrigerant. The receiver-drier is located in the liquid line between the condenser outlet and expansion valve inlet.

SIGHT GLASS: A window in the liquid line or in top of drier used to observe the liquid refrigerant flow.

SUCTION LINE: The line connecting evaporator outlet to compressor inlet.

SUCTION THROTTLING VALVES (STV & POA VALVES): Used on some systems to control refrigerant flow to prevent evaporator freeze-up.

THERMOSTATIC EXPANSION VALVE: A component regulating rate of refrigerant flow into evaporator as governed by evaporator outlet pipe temperatures sensed by the sensing bulb.

VARIABLE DISPLACEMENT COMPRESSOR: A design of compressor that changes its output based on vehicle heat load, rather than cycling the compressor clutch off and on.




Karl Hofmann on Tue February 24, 2004 10:44 AM User is offlineView users profile

Mr BillPro,

LOL I'm in no hurry to croak just yet. It just seems that everything that is fun will get you sent to Hell.

Hell is a place that the established religeons invented, a place that can neither be proved nor disproved, but is used as the ultimate punishment to force the population of a region to adhere to rules and laws long before the establishment of Police forces. Is there any reason these days why a Jew should burn in Hell for eating a pork chop, a muslim for drinking alcohol or a Catholic for wearing a condom?

Those that are truely evil have their own personal Hell as they draw their last breath and think to them selves S##t what happens if there really IS a Hell?

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Never knock on deaths door... Ring the doorbell and run away, death really hates that!

TRB on Tue February 24, 2004 11:17 AM User is offlineView users profile

Quote
Originally posted by: NickD
Here's a start:


Just email me the info when you think you have it.



-------------------------
When considering your next auto A/C purchase, please consider the site that supports you: ACkits.com
Contact: ACKits.com

MrBillPro on Tue February 24, 2004 12:33 PM User is offlineView users profile

The ones Nick listed are just fine, I found these they might be a tad better for the layman or the person that needs a little more elaboration.


COMPRESSOR
Commonly referred to as the heart of the system, the compressor is a belt driven pump that is fastened to the engine. It is responsible for compressing and transferring refrigerant gas.

The A/C system is split into two sides, a high pressure side and a low pressure side; defined as discharge and suction. Since the compressor is basically a pump, it must have an intake side and a discharge side. The intake, or suction side, draws in refrigerant gas from the outlet of the evaporator. In some cases it does this via the accumulator.

Once the refrigerant is drawn into the suction side, it is compressed and sent to the condenser, where it can then transfer the heat that is absorbed from the inside of the vehicle.




CONDENSER
This is the area in which heat dissipation occurs. The condenser, in many cases, will have much the same appearance as the radiator in you car as the two have very similar functions. The condenser is designed to radiate heat. Its location is usually in front of the radiator, but in some cases, due to aerodynamic improvements to the body of a vehicle, its location may differ. Condensers must have good air flow anytime the system is in operation. On rear wheel drive vehicles, this is usually accomplished by taking advantage of your existing engine's cooling fan. On front wheel drive vehicles, condenser air flow is supplemented with an electric cooling fan(s).

As hot compressed gasses are introduced into the top of the condenser, they are cooled off. As the gas cools, it condenses and exits the bottom of the condenser as a high pressure liquid.




EVAPORATOR
Located inside the vehicle, the evaporator serves as the heat absorption component. The evaporator provides several functions. Its primary duty is to remove heat from the inside of your vehicle. A secondary benefit is dehumidification. As warmer air travels through the aluminum fins of the cooler evaporator coil, the moisture contained in the air condenses on its surface. Dust and pollen passing through stick to its wet surfaces and drain off to the outside. On humid days you may have seen this as water dripping from the bottom of your vehicle. Rest assured this is perfectly normal.

The ideal temperature of the evaporator is 32° Fahrenheit or 0° Celsius. Refrigerant enters the bottom of the evaporator as a low pressure liquid. The warm air passing through the evaporator fins causes the refrigerant to boil (refrigerants have very low boiling points). As the refrigerant begins to boil, it can absorb large amounts of heat. This heat is then carried off with the refrigerant to the outside of the vehicle. Several other components work in conjunction with the evaporator. As mentioned above, the ideal temperature for an evaporator coil is 32° F. Temperature and pressure regulating devices must be used to control its temperature. While there are many variations of devices used, their main functions are the same; keeping pressure in the evaporator low and keeping the evaporator from freezing; A frozen evaporator coil will not absorb as much heat.




PRESSURE REGULATING DEVICES
Controlling the evaporator temperature can be accomplished by controlling refrigerant pressure and flow into the evaporator. Many variations of pressure regulators have been introduced since the 1940's. Listed below, are the most commonly found.




ORIFICE TUBE
The orifice tube, probably the most commonly used, can be found in most GM and Ford models. It is located in the inlet tube of the evaporator, or in the liquid line, somewhere between the outlet of the condenser and the inlet of the evaporator. This point can be found in a properly functioning system by locating the area between the outlet of the condenser and the inlet of the evaporator that suddenly makes the change from hot to cold. You should then see small dimples placed in the line that keep the orifice tube from moving. Most of the orifice tubes in use today measure approximately three inches in length and consist of a small brass tube, surrounded by plastic, and covered with a filter screen at each end. It is not uncommon for these tubes to become clogged with small debris. While inexpensive, usually between three to five dollars, the labor to replace one involves recovering the refrigerant, opening the system up, replacing the orifice tube, evacuating and then recharging. With this in mind, it might make sense to install a larger pre filter in front of the orifice tube to minimize the risk of of this problem reoccurring. Some Ford models have a permanently affixed orifice tube in the liquid line. These can be cut out and replaced with a combination filter/orifice assembly.


THERMAL EXPANSION VALVE
Another common refrigerant regulator is the thermal expansion valve, or TXV. Commonly used on import and aftermarket systems. This type of valve can sense both temperature and pressure, and is very efficient at regulating refrigerant flow to the evaporator. Several variations of this valve are commonly found. Another example of a thermal expansion valve is Chrysler's "H block" type. This type of valve is usually located at the firewall, between the evaporator inlet and outlet tubes and the liquid and suction lines. These types of valves, although efficient, have some disadvantages over orifice tube systems. Like orifice tubes these valves can become clogged with debris, but also have small moving parts that may stick and malfunction due to corrosion.


RECEIVER-DRIER
The receiver-drier is used on the high side of systems that use a thermal expansion valve. This type of metering valve requires liquid refrigerant. To ensure that the valve gets liquid refrigerant, a receiver is used. The primary function of the receiver-drier is to separate gas and liquid. The secondary purpose is to remove moisture and filter out dirt. The receiver-drier usually has a sight glass in the top. This sight glass is often used to charge the system. Under normal operating conditions, vapor bubbles should not be visible in the sight glass. The use of the sight glass to charge the system is not recommended in R-134a systems as cloudiness and oil that has separated from the refrigerant can be mistaken for bubbles. This type of mistake can lead to a dangerous overcharged condition. There are variations of receiver-driers and several different desiccant materials are in use. Some of the moisture removing desiccants found within are not compatible with R-134a. The desiccant type is usually identified on a sticker that is affixed to the receiver-drier. Newer receiver-driers use desiccant type XH-7 and are compatible with both R-12 and R-134a refrigerants.


ACCUMULATOR
Accumulators are used on systems that accommodate an orifice tube to meter refrigerants into the evaporator. It is connected directly to the evaporator outlet and stores excess liquid refrigerant. Introduction of liquid refrigerant into a compressor can do serious damage. Compressors are designed to compress gas not liquid. The chief role of the accumulator is to isolate the compressor from any damaging liquid refrigerant. Accumulators, like receiver-driers, also remove debris and moisture from a system. It is a good idea to replace the accumulator each time the system is opened up for major repair and anytime moisture and/or debris is of concern. Moisture is enemy number one for your A/C system. Moisture in a system mixes with refrigerant and forms a corrosive acid. When in doubt, it may be to your advantage to change the Accumulator or receiver in your system. While this may be a temporary discomfort for your wallet, it is of long term benefit to your air conditioning system.



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Don't take life seriously... Its not permanent.

NickD on Tue February 24, 2004 2:16 PM User is offline

Here is another good one explaining common AC terms.

I won't copy and paste this one.

http://www.hvacmall.com/glossary/

So is there life after death? Every theologian I asked this question said in all honesty, you have to have faith to believe so. What is faith? Believing anything without proof.

At the moment, my greatest curiosity is does the Easter Bunny really exist? Or should I go to Wal-Mart and buy some Easter candy?

I do believe if I buy it after Easter, I will get it at 70% off.

MrBillPro on Tue February 24, 2004 2:43 PM User is offlineView users profile

This would be more of my Pastors attitude:

Science is the truth only in matters that can be objectified; in the spiritual world, where values, goals, authority and purpose are located, science has nothing to say, and it is a poor life that is restricted to the scientific standard of truth, where you and I are nothing but a collection of atoms without meaning and purpose. Realizing the narrow-minded nature of science opens the gate to an understanding of God that complements the scientific truth and gives life,love,and peace.



Dang Nick if we had scientists coming here for auto a/c information your link would be great! he! he!



Zoning

A system in which living areas or groups of rooms are divided into separate spaces and each space's heating/air conditioning is controlled independently. This can be accomplished by using either multiple independent systems, or a single system using electronic controls and motorized dampers (see Damper). For example, you might prefer to have the kitchen area of your home be slightly cool, while at the same time keeping the temperature in the bedrooms warmer.


Could this also be used for front seat and back seat applications?


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Don't take life seriously... Its not permanent.

Edited: Tue February 24, 2004 at 2:50 PM by MrBillPro

NickD on Tue February 24, 2004 3:03 PM User is offline

Most scientists believe in a supreme being as nature is so complex, it's just a bit much to be considered an accident. I feel man should help each other and the most tragic sins to mankind are power and greed. Seems to be an over abundance of that lately.

MrBillPro on Tue February 24, 2004 3:28 PM User is offlineView users profile

Now that statement is something i totally agree with you on Nick!!!

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Don't take life seriously... Its not permanent.

Karl Hofmann on Tue February 24, 2004 4:53 PM User is offlineView users profile

To not believe in a supreme being is to not believe in ones own existence, the sticking point is our interpretation of this supreme being, of what it intends for us to do or even if it is conscious of us. But since we can't even decide on what refrigerant to use, perhaps we should put the "G" question on the backburner for a while and I would refer you all to "The Hitchhikers Guide to the Galaxy"

When I eventually get sent to hell, I look forward to buying you all a pint and we can discuss things with a more personal view to the situation that we find ourselves in.

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Never knock on deaths door... Ring the doorbell and run away, death really hates that!

MrBillPro on Tue February 24, 2004 5:14 PM User is offlineView users profile

I look forward to buying you all a pint

Hey Karl, Can we have ours together now just in case i don't end up there

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Don't take life seriously... Its not permanent.

Karl Hofmann on Wed February 25, 2004 3:39 AM User is offlineView users profile

LOL No problem Mr BillPro, Your pub or mine

If you apply yourself and study hard, I'll make a sinner of you yet. I understand that they do a great BBQ down there, but property prices are sky high due to demand

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Never knock on deaths door... Ring the doorbell and run away, death really hates that!

NickD on Wed February 25, 2004 10:04 AM User is offline

With the new highway bypass in town with new road access and intersections, suddenly three new churches are being built at the same intersection. I will have to dig out my books to learn what protestant sect they are and how they originated. Also seems like each is trying to outdo the other with the fanciest buildings, it a sense, and this is mostly based on my manufacturing experience where every square cm of space is costing the stockholders money in taxes and energy costs, efficiency is the key to success. So my thoughts wander as to why these churches are built as a gathering space and only used one or two hours per week.

They have the advantage that with a church or religious building, and many are now adding large social gathering rooms for entertainment or whatever they do there is that property becomes tax exempt. Not only that, but the private home the minister lives in also becomes property tax exempt. My neighbor, a nice guy and all that is pouring the bucks into his home and grounds, man, could I pour the money into my place if I had that money I was paying into taxes let along that any improvements I make increase my taxes. This is further compounded in that any money donated to these institutions is tax deductible meaning that the rest of us have to pay more taxes to compensate for that to meet all those government budgets.

Kind of seems there really isn't any separation from religion and state in these matters. I guess I really don't care if they want to put up some real fancy buildings, but I feel they should at their expense and not mine. It's been my bitter experience in getting involved with church charity matters, that, that expensive piece of art is far more valuable to the community then truly helping the needy. Though most have some kind of very token charity program.

So with all the world problems going on right now, our darn poor economy, shipping all of our industry to foreign pollution regulation free countries, why is Bush making such a big issue out of same sex marriages? Historically, a married couple pays more taxes, so it's no big deal if a couple of gay people want to have a legal agreement between them. Not exactly my life style, but what the hell, if they want to pay more taxes, they have my blessings.

Here we go again, the key issues and problems with this country are being swept under the rug, and we have our leaders telling us what we can view on the web or watch on TV or who can get married now.

The bible makes plenty of references to tending the flock of sheep, a very ignorant, but yet a very trusting animal that needs a strong social environment, namely a whole bunch of other sheep. So what does that tender loving shepherd do? Strips them of their goods and leads them to the slaughter house.

Our leaders treat us like sheep, and I guess if we are dumb to be sheep, we are getting what we deserve. Actually the sheep have it better than us, when sick or ill, they get to die, we have to live and suffer with our ills and diseases until we and our families are stripped cleaned of everything we worked for.

Karl Hofmann on Wed February 25, 2004 5:43 PM User is offlineView users profile

Nick, I couldn't agree with you more.

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Never knock on deaths door... Ring the doorbell and run away, death really hates that!

Anonymous on Wed March 03, 2004 1:04 PM User is offline

You guys should know that the original story quote above was via Dr. Schlambaugh of the U. of Oklahoma Chemical Engineering Dept

MrBillPro on Wed March 03, 2004 1:11 PM User is offlineView users profile

Which story quote above?

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Don't take life seriously... Its not permanent.

NickD on Wed March 03, 2004 2:02 PM User is offline

Must be this one:

http://csmres.jmu.edu/bioweb/bbb/hell.htm

MikeH on Wed March 03, 2004 4:16 PM User is offline

Yep, thats the one.

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