DPM particle tracking

sonnet · March 9, 2018, 10:02

I have noticed that for surface injection the number of particle does not change, with respect to the change of mass flow rate. I am just wondering, why is that.
Since the mass of each particle is constant by the diameter and density, I thought increasing mass flow rate should increase the particle number.

Can anyone please help me to clarify it?

Kummi · March 12, 2018, 02:27

Hello Sonnet,
Have you gone through following posts:

DPM Injections

Controlling Number of particles in Surface Injection (DPM)

Hope it helps..

sonnet · March 13, 2018, 07:41

thanks kummi,
i have read those. but they are not helpful. it still does not explain how same amount of particle capture the increased mass flow, when the dia, velocity and density is predefined. sorry for asking so many questions.
many thanks

sonnet · March 13, 2018, 07:43

moreover, i have tried to do the single injection with the sqipt as shown below. i have saved it as .inj file on the directory. It is not working.
can you please check it.

(( x y z u v w diameter temperature mass-flow ) name )
(( 30 0 -140.98 0 0 31.678 0.25 288 0.5 ) 1 )
((28.97777479 7.764571353 -140.98 0 0 31.678 0.25 288 0.5 ) 2 )
(( 25.98076211 15 -140.98 0 0 31.678 0.25 288 0.5 ) 3 )
(( 21.21320344 21.21320344 -140.98 0 0 31.678 0.25 288 0.5 ) 4 )
(( 15 25.98076211 -140.98 0 0 31.678 0.25 288 0.5 ) 5 )
(( 7.764571353 28.97777479 -140.98 0 0 31.678 0.25 288 0.5 ) 6 )
(( 1.83772E-15 30 -140.98 0 0 31.678 0.25 288 0.5 ) 7 )
(( -7.764571353 28.97777479 -140.98 0 0 31.678 0.25 288 0.5 ) 8 )
(( -15 25.98076211 -140.98 0 0 31.678 0.25 288 0.5 ) 9 )
(( -21.21320344 21.21320344 -140.98 0 0 31.678 0.25 288 0.5 ) 10 )
(( -25.98076211 15 -140.98 0 0 31.678 0.25 288 0.5 ) 11 )
(( -28.97777479 7.764571353 -140.98 0 0 31.678 0.25 288 0.5 ) 12 )
(( -30 3.67545E-15 -140.98 0 0 31.678 0.25 288 0.5 ) 13 )
(( -28.97777479 -7.764571353 -140.98 0 0 31.678 0.25 288 0.5 ) 14 )
(( -25.98076211 -15 -140.98 0 0 31.678 0.25 288 0.5 ) 15 )
(( -21.21320344 -21.21320344 -140.98 0 0 31.678 0.25 288 0.5 ) 16 )
(( -15 -25.98076211 -140.98 0 0 31.678 0.25 288 0.5 ) 17 )
(( -7.764571353 -28.97777479 -140.98 0 0 31.678 0.25 288 0.5 ) 18 )
(( -5.51317E-15 -30 -140.98 0 0 31.678 0.25 288 0.5 ) 19 )
(( 7.764571353 -28.97777479 -140.98 0 0 31.678 0.25 288 0.5 ) 20 )
(( 15 -25.98076211 -140.98 0 0 31.678 0.25 288 0.5 ) 21 )
(( 21.21320344 -21.21320344 -140.98 0 0 31.678 0.25 288 0.5 ) 22 )
(( 25.98076211 -15 -140.98 0 0 31.678 0.25 288 0.5 ) 23 )
(( 28.97777479 -7.764571353 -140.98 0 0 31.678 0.25 288 0.5 ) 24 )
(( 30 -7.35089E-15 -140.98 0 0 31.678 0.25 288 0.5 ) 25 )

March 9, 2018, 10:02	DPM particle tracking	#1
sonnet New Member nirjhor Join Date: Feb 2015 Posts: 7 Rep Power: 11	I have noticed that for surface injection the number of particle does not change, with respect to the change of mass flow rate. I am just wondering, why is that. Since the mass of each particle is constant by the diameter and density, I thought increasing mass flow rate should increase the particle number. Can anyone please help me to clarify it?

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March 12, 2018, 02:27		#2
Kummi Senior Member Kumaresh Join Date: Oct 2016 Posts: 349 Rep Power: 11	Hello Sonnet, Have you gone through following posts: DPM Injections Controlling Number of particles in Surface Injection (DPM) Hope it helps..

March 13, 2018, 07:41		#3
sonnet New Member nirjhor Join Date: Feb 2015 Posts: 7 Rep Power: 11	thanks kummi, i have read those. but they are not helpful. it still does not explain how same amount of particle capture the increased mass flow, when the dia, velocity and density is predefined. sorry for asking so many questions. many thanks

March 13, 2018, 07:43		#4
sonnet New Member nirjhor Join Date: Feb 2015 Posts: 7 Rep Power: 11	moreover, i have tried to do the single injection with the sqipt as shown below. i have saved it as .inj file on the directory. It is not working. can you please check it. (( x y z u v w diameter temperature mass-flow ) name ) (( 30 0 -140.98 0 0 31.678 0.25 288 0.5 ) 1 ) ((28.97777479 7.764571353 -140.98 0 0 31.678 0.25 288 0.5 ) 2 ) (( 25.98076211 15 -140.98 0 0 31.678 0.25 288 0.5 ) 3 ) (( 21.21320344 21.21320344 -140.98 0 0 31.678 0.25 288 0.5 ) 4 ) (( 15 25.98076211 -140.98 0 0 31.678 0.25 288 0.5 ) 5 ) (( 7.764571353 28.97777479 -140.98 0 0 31.678 0.25 288 0.5 ) 6 ) (( 1.83772E-15 30 -140.98 0 0 31.678 0.25 288 0.5 ) 7 ) (( -7.764571353 28.97777479 -140.98 0 0 31.678 0.25 288 0.5 ) 8 ) (( -15 25.98076211 -140.98 0 0 31.678 0.25 288 0.5 ) 9 ) (( -21.21320344 21.21320344 -140.98 0 0 31.678 0.25 288 0.5 ) 10 ) (( -25.98076211 15 -140.98 0 0 31.678 0.25 288 0.5 ) 11 ) (( -28.97777479 7.764571353 -140.98 0 0 31.678 0.25 288 0.5 ) 12 ) (( -30 3.67545E-15 -140.98 0 0 31.678 0.25 288 0.5 ) 13 ) (( -28.97777479 -7.764571353 -140.98 0 0 31.678 0.25 288 0.5 ) 14 ) (( -25.98076211 -15 -140.98 0 0 31.678 0.25 288 0.5 ) 15 ) (( -21.21320344 -21.21320344 -140.98 0 0 31.678 0.25 288 0.5 ) 16 ) (( -15 -25.98076211 -140.98 0 0 31.678 0.25 288 0.5 ) 17 ) (( -7.764571353 -28.97777479 -140.98 0 0 31.678 0.25 288 0.5 ) 18 ) (( -5.51317E-15 -30 -140.98 0 0 31.678 0.25 288 0.5 ) 19 ) (( 7.764571353 -28.97777479 -140.98 0 0 31.678 0.25 288 0.5 ) 20 ) (( 15 -25.98076211 -140.98 0 0 31.678 0.25 288 0.5 ) 21 ) (( 21.21320344 -21.21320344 -140.98 0 0 31.678 0.25 288 0.5 ) 22 ) (( 25.98076211 -15 -140.98 0 0 31.678 0.25 288 0.5 ) 23 ) (( 28.97777479 -7.764571353 -140.98 0 0 31.678 0.25 288 0.5 ) 24 ) (( 30 -7.35089E-15 -140.98 0 0 31.678 0.25 288 0.5 ) 25 )