How to distinguish two trace gases in a moist flow network in Simulink?

I need to input one dry gas, one trace gas and one moisture stream to a constant volume block in simulink. These input values are to be taken from an external tool. I am using two Trace gas source blocks and one moisture source block to realize this. These three streams are connected to the constant volume block. Now, how to distinguish the two gases (dry gas and trace gas added) somewhere after the constant volume block.

If I use Measurement selector, I can get the trace gas information. But, is it sum of both dry gas and trace gas since I am adding dry gas and trace gas using Two Trace gas source blocks.

Or is there any other way I can add the dry gas separately instead of using TraceGas source block.

Requesting a solution on this.

Thank you.

Answer 1

[Yifeng Tang]

Hi @Vidyadhar,

Trace gas source only add, as the name suggests, the trace gas. It won't add any dry air.

To add dry air, the easiest way is to use a reservoir, set up with no water and no trace gas, add a flow source and specify a flow rate. Something like this:

Hope this makes sense.

[Vidyadhar]

Hi @Yifeng Tang, thank you for the detailed response.

I tried this way and encountered issues with respect to temperature at port 'B' of the flow source exceeding the maximum valid temperature value. Currently, I am trying to resolve the issue.

Thank you.

[Yifeng Tang]

check the pressure at that port. it sounds like the flow source needs to add lots of energy to the flow to raise the pressure, in order to achieve the flow rate you commanded. it may be the total flow resistance you have downstream. it may also be that you haven't specify the correct unit. It may also be the cross section area being unreasonable for the flow rate you want.

attaching a model to demonstrate your issue will help.