Experiments in water cooling a mach part 2

[sacha35]

Follow on to part 1 from Bazx.

Results of S/S unit with cheap single rad/pump and twin fan setup.

I started off with the same settings as Bazx 402a, 2.75mts of 0.31 cap tube, but different evap and suction line, the results where around what we had seen from Bazx, but this was using only a single rad and pump.

I Reduced the cap tube lenth for higher loads to 2.65mts and refilled with 402a.
all the results shown are un-insulated as i am awaiting on some insulation, so the end results should be a little bit better than shown.

The results are with two temp probes, T1 is attached to the side of the evap, and T2 is attached 6mm from the rear of the evap on the suction line.

The results shown where with the unit being run for around an hour at each test.

Pic of the S/S using single rad and know insulation.
http://i46.photobucket.com/albums/f124/waterboy100/PICT0015.jpg

[sacha35]

Time for some testing of the water cooled modded Mach.

Unloaded results:
High side 215 psi Low side 4psi
http://i46.photobucket.com/albums/f124/waterboy100/PICT0017.jpg

Unloaded T1 temps: -59.2c
http://i46.photobucket.com/albums/f124/waterboy100/PICT0026.jpg

Unloaded T2temps: -58.0c
http://i46.photobucket.com/albums/f124/waterboy100/PICT0027.jpg

very small amount of floodback, but this will be not be a problem as know load is on the unit, with only 50watts load applied the flooback had gone.
http://i46.photobucket.com/albums/f124/waterboy100/PICT0018.jpg

[sacha35]

And some loaded tests.

Loaded results:
303watt load applied.

High side 260psi, Low side 9psi
http://i46.photobucket.com/albums/f124/waterboy100/PICT0013.jpg

Loaded T1 temps: -33.9c
http://i46.photobucket.com/albums/f124/waterboy100/PICT0009.jpg

Loaded T2 tepms: -30.3c
http://i46.photobucket.com/albums/f124/waterboy100/PICT0012.jpg

[sacha35]

I have double checked the meters as it seams the results are to good to be true, here are my findings.

fluke double checked in ice water against analog MT4C meter.
http://i46.photobucket.com/albums/f124/waterboy100/PICT0049.jpg

Ambient temp:
http://i46.photobucket.com/albums/f124/waterboy100/PICT0054.jpg

Re-checked in ice water:
http://i46.photobucket.com/albums/f124/waterboy100/PICT0048.jpg

Gauges changed to rule out any discrepancies, will post re-test latter.

[sacha35]

Pic of the water setup. cheapo rad and pump.
http://i46.photobucket.com/albums/f124/waterboy100/PICT0001.jpg

Diferant gauges attaced, lost a small amount of 402a as you can see it is only reading 200psi on the high side but the low side gauge was not reading correctly as you can see in the pic it is now -10psi.
http://i46.photobucket.com/albums/f124/waterboy100/PICT0005.jpg

[sacha35]

Some pics of HX temps on the water setup

T1 water inlet unloaded.
http://i46.photobucket.com/albums/f124/waterboy100/PICT0008.jpg

T2 water outlet unloaded.
http://i46.photobucket.com/albums/f124/waterboy100/PICT0009-1.jpg

HX temps loaded.

T1 water inlet.
http://i46.photobucket.com/albums/f124/waterboy100/PICT0012-1.jpg

T2 water outlet.
http://i46.photobucket.com/albums/f124/waterboy100/PICT0013-1.jpg

[sacha35]

Just A little bit of whats to come from this small NL11, will post up some more results latter.

-45.1 @ 259watts
http://i46.photobucket.com/albums/f124/waterboy100/PICT0001-1.jpg

[sacha35]

Time for some 410a action.

Load at 353watts it was 260psi-270psi for the high side and 11 psi for the low side

http://i46.photobucket.com/albums/f124/waterboy100/PICT0006.jpg

As you can see the high side was going a bit mental with this load applied.
http://i46.photobucket.com/albums/f124/waterboy100/PICT0008-1.jpg

I think this must be some kind of record for a S/S and its only an NL11:)

[sacha35]

More results of some 410a action:

Today i shortened the 0.31 cap tube to 2.55mts, and put a static charge of 2bar in the unit.

I was surprised to see an unloaded temperature of -64c in T1 and -62.7 in T2,with this amount of cap tube.

T1 -64c
http://i46.photobucket.com/albums/f124/waterboy100/PICT0002-1.jpg

T2 -62.7c
http://i46.photobucket.com/albums/f124/waterboy100/PICT0003-2.jpg

[sacha35]

Time for some 410a loaded action.

I added more 410a refrigerant and set the load tester to 203watts, and left to run for two hours.

The results of this are as follows:
T1 -47.4c
http://i46.photobucket.com/albums/f124/waterboy100/PICT0004-1.jpg

T2 -46.3c
http://i46.photobucket.com/albums/f124/waterboy100/PICT0005-2.jpg

Hx water temperature:

T1 +38c
http://i46.photobucket.com/albums/f124/waterboy100/PICT0008-2.jpg

T2 +24c
http://i46.photobucket.com/albums/f124/waterboy100/PICT0009-3.jpg

[sacha35]

Results of the HX temperature at 203watts of load

T1 +38c
http://i46.photobucket.com/albums/f124/waterboy100/PICT0008-2.jpg

T2 +24c
http://i46.photobucket.com/albums/f124/waterboy100/PICT0009-3.jpg

Highside pressure +240psi, Lowside pressure + 2psi
http://i46.photobucket.com/albums/f124/waterboy100/PICT0007.jpg

Compressor temperature +60.4c
http://i46.photobucket.com/albums/f124/waterboy100/PICT0018-2.jpg

[sacha35]

Time for some more load to be added to the evap.

Same amount of 410a refrigerant left in the unit and set the load tester to 259watts 1 hour run.

T1 -45.3c
http://i46.photobucket.com/albums/f124/waterboy100/PICT0011-1.jpg

T2 -44.1c
http://i46.photobucket.com/albums/f124/waterboy100/PICT0012-3.jpg

HX water temperature:

T1 +41c
http://i46.photobucket.com/albums/f124/waterboy100/PICT0013-3.jpg

T2 +24c
http://i46.photobucket.com/albums/f124/waterboy100/PICT0014-2.jpg

[sacha35]

The pressures for the 259watt run

High side pressure +250psi, Lowside pressure + 3psi
http://i46.photobucket.com/albums/f124/waterboy100/PICT0015-2.jpg

Compressor temperature know change still at +60.4c

I tried a higher load of 303watts but with this amount of refrigerant and the cap tube lenth the unit was not able to substain this load like when the S/S had 2.65 mts of cap tube, but what i have found by shortening the cap tube is that i can use less refrigerant for upto 260watts of load and the pressure are a lot lower and are now very stable.

[sacha35]

Compressor back to unloaded test Results.

I left the unit to run without any load for 15 minuets and as you can see there is know flood back at all the ice comes within 2mm of the compressor, which shows it is not overcharged at all.
Know floodback:

http://i46.photobucket.com/albums/f124/waterboy100/PICT0030-1.jpg

The temps with know load are as follows.

T1 -56.4c
http://i46.photobucket.com/albums/f124/waterboy100/PICT0028-1.jpg

T2 -55.1c
http://i46.photobucket.com/albums/f124/waterboy100/PICT0029-1.jpg

[sacha35]

Unloaded HX temps and pressures.

HX water temps:

T1 +31c
http://i46.photobucket.com/albums/f124/waterboy100/PICT0024.jpg

T2 +22c
http://i46.photobucket.com/albums/f124/waterboy100/PICT0025.jpg

Highside pressure +215psi, Lowside pressure -5psi
http://i46.photobucket.com/albums/f124/waterboy100/PICT0023.jpg

Compressor temperature +54.1c but this single stage had been running for well over 3 hours none stop so this could be a little lower.
http://i46.photobucket.com/albums/f124/waterboy100/PICT0026-1.jpg

Anyway i think i can say i am about done here now with this unit all that is left to do is some insulation and a few finnal tweaks and then bolt it up to my quad core to see how it does.

I think the main benefits of using this type of water cooled HX are its nice and quite even with a single rad and fan it could Handel the 402a loads that where thrown at it, also as you can see in this test i am using straight 410a in a small NL11 compressor with know problems at all (but this had to be run with a water butt as the single rad would not be able to cope with the higher temperature's) this is just not possible at all with a conventional condenser as the pressures would be far to high for this type of compressor to Handel, the outer benefits i have found is that the unit needs far less refrigerant than a conventional condenser so saving money, and the final benefit we have all seen is that we can get higher and better loads from this HX than a standard condenser, don't ask me why this is but you have all seen me run 402a and 410a and the pressures are far lower and with better results.

[Glacius]

Just thought I'd let you know, for informations sake, I did some calculations.

When you are running with a load of 259W, the flowrate of liquid refrigerant through your cap tube is approximately 148 ml/min.

I have some other numbers but I seem to have messed up reading from the R410a tables :'(

For future reference, Thermodynamic Properties of R410a: http://refrigerants.dupont.com/Suva/en_US/pdf/h64422.pdf

Pretty handy!

[SoddemFX]

Using r410a with a liquid outlet temperature from the heat exchanger of 25C, an evaporator pressure of 0PSIg, 15K exit superheat and 259W of evaporator load i get a mass flow of 1.55grams per second. At 25C the liquid density is 1062kg/m^3 which would be a liquid volumetric flow of 1.46cc / sec which would be 87.6ml/min :)

I used a program called CoolPack (which is free) to give cycle data and thermo properties of r410a:

http://www.et.web.mek.dtu.dk/Coolpack/UK/index.html

Sorry to go off topic Paul. Glacius if you want to talk about this sort of stuff feel free to start a new thread or PM etc. That is a good data sheet tho :)

Tom

[sacha35]

Using r410a with a liquid outlet temperature from the heat exchanger of 25C, an evaporator pressure of 0PSIg, 15K exit superheat and 259W of evaporator load i get a mass flow of 1.55grams per second. At 25C the liquid density is 1062kg/m^3 which would be a liquid volumetric flow of 1.46cc / sec which would be 87.6ml/min :)

I used a program called CoolPack (which is free) to give cycle data and thermo properties of r410a:

http://www.et.web.mek.dtu.dk/Coolpack/UK/index.html

Sorry to go off topic Paul. Glacius if you want to talk about this sort of stuff feel free to start a new thread or PM etc. That is a good data sheet tho :)

Tom

Hay Tom know problems mate, your knowledge and information is greatly welcomed and a big help to us all.