I took AP Physics (failed) back in high-school, and I've retained most of the information, but we didn't delve too far into thermo-dynamics, instead focusing mostly on resistance, acceleration, velocity, friction, ect...(adsbygoogle = window.adsbygoogle || []).push({});

I am trying to calculate a few things to determine the average temperature of a liquid in a system after the system is in motion....

What I'm doing is trying to calculate and work this system out before I build it. I'm going to water-cool my PC. I am going to put the reservoir inside of a mini-fridge, and the radiator(s) in front of an Air Conditioning unit. Everything connected together by tubes to create a closed system loop.

[PLAIN]http://www.zombiefire.com/ocn/crazyidea.png [Broken]

Since I'm not that knowledgable about thermodynamics I did a bit of research before I started and began to determine my variables.

1) BTU of mini-fridge

2) Heat Given off by CPU

3) BTU of A/C unit.

4) Initial temperature of water

5) Rate of dissipation of heat from a Radiator. (cooled by A/C). Obviously you won't have 100% efficiency and have all 5000 BTU of the A/C into the Radiator....

6) Amount of liquid in the loop. (resevoir + tubing + Radiator)

7) Ambient air temperature. (outside the system)

8) Speed of fluid pumped through system (effecting heat absorption)

9) Friction of fluid through system (increasing heat)

10) Thermal capacity of water.

I'm not sure if I've forgotten any variables....

I then tried to teach myself some basic thermo-dynamics and get some of the variables from around the internet:

Now for this system to work correctly, the temp. of the fluid in the system has to be at or below a certain temperature (the Fridge isn't made to be on 100% of the time, but instead is meant to cycle on and off. I don't want to burn out the fridge). A/C 5200 BTU = (~~1500 Watts)

AMD Phenom II x4 965 CPU ~~ 125 Watts (more if overclocked?)

Mini-Fridge = 330 BTU?

A large mini fridge (3.2 cu ft) has a surface area of around 1.85 meters squared. Its walls are made of 1" styrofoam, with a metal or plastic casing. Assuming there is free convection on all surfaces of the fridge, and the fridge is at 4 degrees C in a 22 degree C room, the heat transfer out of the fridge is around 20 watts. (this value is probably a little high, I haven't counted a lot of the smaller thermal resistances)

1 ton of refrigeration is the rate of heat removal required to freeze a short ton (i.e., 2000 pounds) of water at 32 Â°F in 24 hours. Based on the heat of fusion for water being 144 Btu per pound, 1 ton of refrigeration = 12,000 Btu/h = 12,660 kJ/h = 3.517 kW++

I'm not really sure where to go from here. If anyone could get me started, give me some pointers and point me towards the right direction?

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# Complex Thermo-Dynamic System of Equations

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