Vapor compression

[ruzfactor]

I need help
This is the simple vapor compression cycle setup I'm working on(attachment)

How do I vary the pressure to change the evaporator and condenser temperature??
What modern refrigeration modification can be applied to this simple setup?



Thanks

[Brian_UK]

You could vary the condensing temperature by use of a variable speed condenser fan.

[narkom]

Capillary tube length will also change evap. end cond. temperature.

[Tapas K Mitra]

It is not clear why you want to change cds and evp pr. Many things can be done but it depends on what is your goal and problem.

[ruzfactor]

I want this setup to be used on experimental purpose. I want to show variation of COP with the change in condenser and evaporator temp. I also want to add some intelligent control to the system. I need some idea on the modification of this setup.

[Pooh]

Firstly why have you a sight glass on a system with a capillary line also a capillary line is not the best way of having a variable system as you are working on a critically charged system. You would be better with a TEV or electronic control. I have a heat pump system that I can vary the condenser temperature and the evaporator temperature to alter COP which works really well.

POOH

[ruzfactor]

I didn't construct the system. I have to do the modification of the system. This system also had a solenoid valve which I had to remove because of its non functionality. What is the main purpose of using a solenoid valve?? What type of control system can be built on this system? I need help.

[ruzfactor]

Pressure gauges used in the setup are all analogue gauges. What should I do to make them digital?

[Tesla]

For accuracy you could use a yellow jacket ritchie superheat calculation kit with an electronic pressure transducer and electronic temp sensor. As for the evap press change a cheep way would be use two capillaries with solanoids with OR and AND function would give three equivalent capillary lengths, or just use an EEV. As for the condenser a variable bypass valve effectivly reduces size of cond and temp, variable fan speed would also work. In any case if you change the condenser characteristics there would need to be some sort of reciever to hold excess refrigerant. Then there will be some sort of controller - there are so many out there to do the job, look for one that is reasonably fast and can interface with computer to trend data logs for diagnostics and control fine tunning. If you added a refrigerant flow metre you could measure enthalpy. If the controller had good software it could plot your system characteristics on a pH chart.

[ruzfactor]

Is it possible to have controlled condenser and evaporator temp. by doing the following things:
Load on the evaporator chamber will be controlled by controlling the water flow rate. Both water inlet and outlet temp. will be measured. Similarly, condenser will reject heat on water(instead of air). Also the water inlet and outlet temp would be measured here. I'm thinking of a shell and tube condenser for this purpose.

[ruzfactor]

Is there any software where I can design a refrigeration system with desired components(not autocad) which are given in the software(e.g. compressor, txv, evap., condenser, pumps etc.)?

[nike123]

Is there any software where I can design a refrigeration system with desired components(not autocad) which are given in the software(e.g. compressor, txv, evap., condenser, pumps etc.)?
http://www.coolit.co.za/

[sterl]

What you are trying to build is a Calorimeter. There are a flock of types, sizes, intents and precision levels and similar available; the most precise versions use all DC-Power Level electrics for all heat sources, pump motors, fan motors and the like.