Temperature control valve (G)

I am trying to develop a gas netwrok in which I am trying to control the flow of gas in the netwrok with the help of temperature control valve .

There's two things I am facing ,

1)There is no flow established in the newtork around the valve though I have add mass flow rate block in the system

2)Temperature control valve is not control the flow of the gas in the network even after defining the actuation temperature .

I am attaching my model with this.

Please help me out in this matter asap

Waiting for response.

[omkar tulankar]

Hi ,

I tried to establish the flow with the by establishing high pressure and low pressure reservoir in gas network.

I am using two valves gate valve and temperature control valve.

Gate valve conditional opening and closing is established with the help of switch block .

While working with temperature control valve , when I am providing a condtion to close above activation temperature , the volumetric flow rate gets zero when valves closes,but the volumetric flow rate is also getting affected at gate valve end where though the gate valve is open , the volumetric flow rate gets to zero .

Any solutions for this issue ?

[Pratyush Roy]

Hi,

Can you attach the modified Simulink model so that I can reproduce your problem from my end?

[omkar tulankar]

Hi Pratyush,

Attaching the updated model .

Waiting for your response .

Please let me know if any queries are there regarding the model to make my problem understandable.

Thanks in advance

Answer 1

[Pratyush Roy]

Hi,

The behaviour from the model is expected. The temperature control valve, the constant volume chamber and the gate valve are connected in series. The activation temperature of the temperature control valve controls the pressure condition which in turn controls the volumetric rate.So the volumetric flow rate at gate value is not independent of the choice of the activation temperature.

Hope this helps!

[omkar tulankar]

Hi pratyush,

I wanted from this model is that both the valve should work independently and have diffrent effects on volumetric flow rate.

I have two constant volume chamber in my model , one is connected to gate valve and other is connected to temperature control valve.

So as per your suggestion , the volumetric flow rate is affected due to opening and closing of temperature control valve as it is connected in series, what I thought is the volumetric flow rate after the valve should get affecting by its opening or closing conditon and before flow rate shlould remain same .

I am not sure where I am getting wrong whether my understanding is wrong or valve is not placed properly .

What I want is volumetric flow change should be observed after the valve and conditions before valve should remain same .

Hope I am clear.

Please let me know if any such thing is possible .

Thanks

[Pratyush Roy]

Hi Omkar,

Here are a few questions whose answers might help us provide better support:

1. Can you give us a broad level picture of what you are trying to design?
2. Also can you specify the known and unknown factors while designing your model?

Thanks.

[omkar tulankar]

Hi Pratyush,

I am trying to define a process called regenerative thermal oxidizer.

This process is used to treat Volatile organic compounds.

Here the temperature of gas is raised to desired setpoint temperature (1500k) with the help of furnace and then the temperature of gas is lowered down again to room temperature before moving gases to atmoshphere.

For above stated method , I am trying to control the flow of gas by condtional opening and closing of valves (conditon being temperature).

Two valves I am trying to use :

1)Gate Valve

2)Temperature control valve

1)Gate valve would get opened when temperature of furnace is raised to 1500k(till then it would remain closed).

Once the setpoint temperature is reached , the flow would be established into the system.

2)Temperature control valve would open when temperature is <=300k (room temperature).

What I intend is opening and closing of any valve should affect the volumetric flow rate after the valve in gas system. Conditons before the valve should remain same.

Known factors:

1)Temperature to be maintained into the system

2)Gas properties of which flow is to be controlled.

Unknown factors:

1)Design specifications of the valves(I am OK with default conditons my major concern is to record the flow changes with the help of valves).

I hope things are clear now .

Thanks

[Pratyush Roy]

Hi Omkar,

When the gate valve is open, there has to be some source to generate the flow. So consider some source of flow so that even after the valve is open, the flow can take place. Also, the temperature control valve will not allow any flow if it is shut off. You can consider a second path to divert the flow in case your first pipe has a valve to block the flow.

Hope this helps!