Particle Tracking_Particle Number Rate

sakurabogoda · March 17, 2014, 03:19

Hi All,
I can understand particle number rate represents number of representative particles. But it is defined as,

Number Rate is determined from the mass flow rate assigned to the representative particle divided by the mass of an actual particle.

Here,
how to define mass of an actual particle for poly dispersed sample?
mass flow rate -mentioned to actual mass flow rate?

Can any body help me, I think I have misunderstood the definition.

sakurabogoda · March 17, 2014, 10:17

Could you please help me???

At least to clarify the definition???

My problem is for poly dispersed particle situation, the mass flowrate of each particle track should be different. (according to the standard div.).
So, if I if I add 250 number of points and inject particles for only 10 time steps (total particles= 250*10=2500) for a particle sample (1-10um, std=2.75) then, will there be similar no. of particles at each particle track?

Really appreciate your help.

ghorrocks · March 17, 2014, 16:21

The particle mass is defined by the particle size (diameter) and material density.

So a specified mass flow will result in a lot of small particles (as each particle has small mass) or a smaller number of large particles.

sakurabogoda · March 17, 2014, 19:01

Dear Glenn,
Thanks a lot. Yes, I got it as assigned no. rate will follow the given PSD.
then, my next question is, if I defined, for given X mass flow rate, no rate as 1000 for 10000 particles, then one particle represent 10 real particles. but in simulations, I can got only 1000 particles.
next time use a doubled mass flow rate, 2X, and assign no rate as 1000 for 20000 particles which specified 20 particles by one representative particles, and here also I can see only 1000 particles in simulation.
then, is there any different in results?

(I am really sorry, if I try this, I have to spend more time, and I have a very limited time to finish this.)

ghorrocks · March 17, 2014, 19:45

Yes, it is a bit complex working out how all the stuff works. I do not have time to chase this up for you, you are going to have to work that out for yourself.

March 17, 2014, 03:19	Particle Tracking_Particle Number Rate	#1
sakurabogoda Senior Member S.Bogoda Join Date: Jul 2012 Posts: 133 Rep Power: 13	Hi All, I can understand particle number rate represents number of representative particles. But it is defined as, Number Rate is determined from the mass flow rate assigned to the representative particle divided by the mass of an actual particle. Here, how to define mass of an actual particle for poly dispersed sample? mass flow rate -mentioned to actual mass flow rate? Can any body help me, I think I have misunderstood the definition.

March 17, 2014, 10:17		#2
sakurabogoda Senior Member S.Bogoda Join Date: Jul 2012 Posts: 133 Rep Power: 13	Could you please help me??? At least to clarify the definition??? My problem is for poly dispersed particle situation, the mass flowrate of each particle track should be different. (according to the standard div.). So, if I if I add 250 number of points and inject particles for only 10 time steps (total particles= 25010=2500) for a particle sample (1-10um, std=2.75) then, will there be similar no. of particles at each particle track? Really appreciate your help. Last edited by sakurabogoda; March 17, 2014 at 11:49.*

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March 17, 2014, 16:21		#3
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,700 Rep Power: 143	The particle mass is defined by the particle size (diameter) and material density. So a specified mass flow will result in a lot of small particles (as each particle has small mass) or a smaller number of large particles.

March 17, 2014, 19:01		#4
sakurabogoda Senior Member S.Bogoda Join Date: Jul 2012 Posts: 133 Rep Power: 13	Dear Glenn, Thanks a lot. Yes, I got it as assigned no. rate will follow the given PSD. then, my next question is, if I defined, for given X mass flow rate, no rate as 1000 for 10000 particles, then one particle represent 10 real particles. but in simulations, I can got only 1000 particles. next time use a doubled mass flow rate, 2X, and assign no rate as 1000 for 20000 particles which specified 20 particles by one representative particles, and here also I can see only 1000 particles in simulation. then, is there any different in results? (I am really sorry, if I try this, I have to spend more time, and I have a very limited time to finish this.)

March 17, 2014, 19:45		#5
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,700 Rep Power: 143	Yes, it is a bit complex working out how all the stuff works. I do not have time to chase this up for you, you are going to have to work that out for yourself.