Flow Test Guide

This guide indicates the current flow and pressure capabilities of a number of items, as an indicator as to when to use them in your own setups.

Fortunately, there are not to many items that can actively move gases along pipes;

• Active Vent,
  
• Pipe Volume Pump,
  
• Pipe Gas Mixer,
  
• Atmospherics.

Pipe Rig Setups

To ensure an even test, all the rigs were configured with essentially the same pipe network, and with enough connections for proper operation.

This was done on Mars so that an independent gas supply would not be needed, and a passive to passive rig was set to ensure we had a standard pressure to compare against.

Only the Active Vent test rig did not use a Passive Vent for input.

The Pipe Volume Pump was set to the maximum of 100L for this test.
Other test results will be included.

For the Pipe Gas Mixer, both inputs were connected to Passive Vents, and the mixer set to 50%/50%.
Test results for different ratios will be included if they indicate a different result.

The Air Conditioner setup was more of a challenge due to the Waste pipe network trending towards ambient temperature, so if I did the test at night, I would need to set the A/C target temperature lower than if I ran the test during the day.

Since the Martian atmosphere is mostly CO2, I used those filters in the Filtration Unit but just had the Unfiltered output dump to a Passive Vent.

The Electrolyzer didn't have an H2O input, so this test might be redundant, in that if it actually splits the input to O2 and Volatiles, what output pressures are produced?
I'll include a test with an H2O source to see what result is obtained.

Test Results

To set up for the test, all the output valves were opened and the canisters allowed to equalise at atmospheric pressure of around 2kPa (higher during the day, lower at night).

I also only ran the items for 1 minute, because the Active Vent would over-pressure if I ran it for much longer.

The results are:

• Active Vent = 2.90MPa
  
• Pipe Volume Pipe @ 100L = 62.5kPa
  
• Pipe Gas Mixer @ 50/50 = 197.6kPa
  
• Air Conditioner = 118.8kPa
  
• Filtration = 125.0kPa
  
• Eloctrolyzer = 131.8kPa

Additional results are:

• Pipe Volume Pipe @ 10L = 6.4kPa
  
• Pipe Volume Pipe @ 50L = 32.5kPa
  
• Pipe Gas Mixer @ 100/0 = 89.1kPa
  
• Pipe Gas Mixer @ 75/25 = 148.0kPa
  
• Pipe Gas Mixer @ 0/100 = 88.5kPa
  
• Electrolyzer @ 7.71MPa H2O = 18MPa for the original rig before the canister blew just before the minute was up.
  
• Electrolyzer @ 7.71MPa H2O = 839.2kPa going to a small tank.

Summary

When maximum pipe gas flow is needed, it seems a mixer with both inputs connected to the same source will produce a far greater output than the volume pump, albeit, without the same level of control.

For atmosphere to pipe flow, nothing beats the Active Vent. It's default setting is considerably high, most likely to ensure that the standard airlock configuration does not take too long to fill or empty.

The Electrolyzer seems to convert H2O to O2 and H very quickly, but these tests did not indicate if that id affected by the input water pressure.

Any other relevant information gleaned from comments and other tests will be added when needed.

[Teamkiller]

and also try to test different pipe network sizes (by adding appendexses of differnt length). Pressure regulator flow depends on total pipe volume after them

[sibrit]

Interesting idea. I will try that. I still have the saved game that this setup was in. Thanks.

[Teamkiller]

The problem with your setup is the quite low passive vent flow rate (that explains mixer double rate since it uses 2 vents for inputs). You'd better test for time nedded to pump say 1MPa from one tank to another.