What mean by "from mass constraint" in plasma model

tomchiah · November 21, 2023, 10:40

Hi all,

I noticed under plasma model, for the settings of each species it has the tick option of 'from mass constraint' may I know what is this means? The screenshot is shown in the attachment Screenshot 2023-11-21 190026.jpg

aminem · December 26, 2023, 07:27

It's mean simply calculated by X(N)= 1-X(1)-X(2)-X(3)-...-X(N-1). X(1) to X(N-1) are masse fraction of other species.

tomchiah · December 26, 2023, 09:06

I noticed, that by setting different species to mass constraint can result as converging error. So far what I know is to set the largest species to mass constraint is the correct way of doing it.

aminem · December 27, 2023, 03:23

You should put only one specie to mass constraint

tomchiah · December 27, 2023, 08:27

But is the one species must be the largets one? That is what I am trying to ask.

November 21, 2023, 10:40	What mean by "from mass constraint" in plasma model	#1
tomchiah Member Chiah Zi Jing Join Date: Oct 2023 Location: Xiamen University Malaysia (XMUM) Sepang, Malaysia Posts: 38 Rep Power: 3	Hi all, I noticed under plasma model, for the settings of each species it has the tick option of 'from mass constraint' may I know what is this means? The screenshot is shown in the attachment Screenshot 2023-11-21 190026.jpg

December 26, 2023, 07:27		#2
aminem Member amine Join Date: Jan 2014 Location: FRANCE Posts: 84 Rep Power: 12	It's mean simply calculated by X(N)= 1-X(1)-X(2)-X(3)-...-X(N-1). X(1) to X(N-1) are masse fraction of other species. tomchiah likes this.

December 27, 2023, 03:23		#4
aminem Member amine Join Date: Jan 2014 Location: FRANCE Posts: 84 Rep Power: 12	You should put only one specie to mass constraint tomchiah likes this.

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December 26, 2023, 09:06		#3
tomchiah Member Chiah Zi Jing Join Date: Oct 2023 Location: Xiamen University Malaysia (XMUM) Sepang, Malaysia Posts: 38 Rep Power: 3	I noticed, that by setting different species to mass constraint can result as converging error. So far what I know is to set the largest species to mass constraint is the correct way of doing it.

December 27, 2023, 08:27		#5
tomchiah Member Chiah Zi Jing Join Date: Oct 2023 Location: Xiamen University Malaysia (XMUM) Sepang, Malaysia Posts: 38 Rep Power: 3	But is the one species must be the largets one? That is what I am trying to ask.