How to Monitor pressure at different voltages

AK5 · October 31, 2015, 12:33

Hi guys, i have just stated to learn CFD.
Please can any one tell me how to apply different voltages to a fully enclosed component which has a heating coil so that i can monitor pressure change for any minute variation in the voltage.

Right-now am able to apply one voltage at a time

Best Regards

ghorrocks · October 31, 2015, 20:17

CFD means computational FLUID dynamics. Voltage does not normally come into it. Can you explain what you are doing?

AK5 · November 1, 2015, 00:57

Thankyou for your reply,

Actually i am trying to see how the Gay-Lussac's law works by introducing a heating coil in a constant Volume and see the changes temperature,Voltage and Pressure. I have taken a cube of 50 X 50 X 50(mm) and introduced a heating coil having a voltage of 5V. I want to see the pressure and temperature for a minute change in voltage say (5, 5.1 ,5.5, 6 ....)V.
I have learnt this application of voltage by a CFX tutorial named Heating Coil.
And study the Fluid Flow.

Thankyou for reply in Advance.

ghorrocks · November 1, 2015, 03:50

If you are investigating the Gay-Lussac stuff (which does not involve voltage) then why not just apply a heat source. This does not require and voltage or any input other than the amount of heat to apply. Why complicate it by using a voltage source to generate the heat?

AK5 · November 1, 2015, 04:16

Thanks for replying

I wanted to study it differently by applying voltage so that i can see the pressure variation for voltage change. Its a law so it has to work no matter how i apply the heat source. I want to do this because i have considered the cube is thermally insulated from all the sides.

Thankyou for the reply in Advance

ghorrocks · November 1, 2015, 04:38

If you just want a power input then why not just specify a heat input? Why complicate it by generating the heat by an electric current?

And another issue - if the cube is insulated then its temperature will increase forever as you apply the power. This will not have a steady state answer. Or are you looking at the transient result?

AK5 · November 1, 2015, 07:05

Thanks for the reply

Is there any way that i can give different voltages in steady state or i have to do it in transient?
I think temperature will increase depending on the electrical resistance of the coil and the voltage applied.
Answer to the first question is, i want this cube to be enclosed by another component say cube of little bigger dimensions, so i want provide electricity to heating coil so that i can generate temperature by resistance and inturn pressure.

Thankyou

ghorrocks · November 1, 2015, 17:11

* Use a heat source to create the heat. Do not use a voltage to generate the heat. Forget about the voltages! You are a beginner to CFD and there is no need to make thing complex by using a voltage to generate heat. Just generate the heat directly.
* If you want to do a steady state simulation (and I recommend you do this, it is simpler and quicker) you need to have a setup which actually has a steady state solution. This means heat needs to go in somewhere (your heat source) and it needs to go out somewhere. Currently you have nowhere for the heat to leave. You need to put some form of thermal boundary in to take the heat away.

AK5 · November 2, 2015, 01:26

Thanks for your Suggestions
I will consider them and get back.

Thankyou

October 31, 2015, 12:33	How to Monitor pressure at different voltages	#1
AK5 New Member Join Date: Oct 2015 Posts: 17 Rep Power: 10	Hi guys, i have just stated to learn CFD. Please can any one tell me how to apply different voltages to a fully enclosed component which has a heating coil so that i can monitor pressure change for any minute variation in the voltage. Right-now am able to apply one voltage at a time Best Regards

October 31, 2015, 20:17		#2
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,703 Rep Power: 143	CFD means computational FLUID dynamics. Voltage does not normally come into it. Can you explain what you are doing? AK5 likes this.

November 1, 2015, 03:50		#4
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,703 Rep Power: 143	If you are investigating the Gay-Lussac stuff (which does not involve voltage) then why not just apply a heat source. This does not require and voltage or any input other than the amount of heat to apply. Why complicate it by using a voltage source to generate the heat? AK5 likes this.

November 1, 2015, 17:11		#8
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,703 Rep Power: 143	* Use a heat source to create the heat. Do not use a voltage to generate the heat. Forget about the voltages! You are a beginner to CFD and there is no need to make thing complex by using a voltage to generate heat. Just generate the heat directly. * If you want to do a steady state simulation (and I recommend you do this, it is simpler and quicker) you need to have a setup which actually has a steady state solution. This means heat needs to go in somewhere (your heat source) and it needs to go out somewhere. Currently you have nowhere for the heat to leave. You need to put some form of thermal boundary in to take the heat away. AK5 likes this.

November 1, 2015, 00:57		#3
AK5 New Member Join Date: Oct 2015 Posts: 17 Rep Power: 10	Thankyou for your reply, Actually i am trying to see how the Gay-Lussac's law works by introducing a heating coil in a constant Volume and see the changes temperature,Voltage and Pressure. I have taken a cube of 50 X 50 X 50(mm) and introduced a heating coil having a voltage of 5V. I want to see the pressure and temperature for a minute change in voltage say (5, 5.1 ,5.5, 6 ....)V. I have learnt this application of voltage by a CFX tutorial named Heating Coil. And study the Fluid Flow. Thankyou for reply in Advance.

November 1, 2015, 04:16		#5
AK5 New Member Join Date: Oct 2015 Posts: 17 Rep Power: 10	Thanks for replying I wanted to study it differently by applying voltage so that i can see the pressure variation for voltage change. Its a law so it has to work no matter how i apply the heat source. I want to do this because i have considered the cube is thermally insulated from all the sides. Thankyou for the reply in Advance

November 1, 2015, 04:38		#6
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,703 Rep Power: 143	If you just want a power input then why not just specify a heat input? Why complicate it by generating the heat by an electric current? And another issue - if the cube is insulated then its temperature will increase forever as you apply the power. This will not have a steady state answer. Or are you looking at the transient result?

November 1, 2015, 07:05		#7
AK5 New Member Join Date: Oct 2015 Posts: 17 Rep Power: 10	Thanks for the reply Is there any way that i can give different voltages in steady state or i have to do it in transient? I think temperature will increase depending on the electrical resistance of the coil and the voltage applied. Answer to the first question is, i want this cube to be enclosed by another component say cube of little bigger dimensions, so i want provide electricity to heating coil so that i can generate temperature by resistance and inturn pressure. Thankyou

November 2, 2015, 01:26		#9
AK5 New Member Join Date: Oct 2015 Posts: 17 Rep Power: 10	Thanks for your Suggestions I will consider them and get back. Thankyou