CFD Online Discussion Forums

CFD Online Discussion Forums (https://www.cfd-online.com/Forums/)
-   FLUENT (https://www.cfd-online.com/Forums/fluent/)
-   -   Diameter of particle dpm (https://www.cfd-online.com/Forums/fluent/147164-diameter-particle-dpm.html)

DrFloyd January 14, 2015 12:34

Diameter of particle dpm
 
Hi everybody,

i have problem with transient injection in a dpm simulation. i should want an injection of particle with the diameter of nozzle-hole, then with "point injection" the particle diameter should be the same of diameter point, that i set 0.00014 m.

I can't undertand why there are particle with diameter that is 0.00025m!

Can you help me?

thank you!!

fishball January 20, 2015 05:33

Quote:

Originally Posted by DrFloyd (Post 527509)
Hi everybody,

i have problem with transient injection in a dpm simulation. i should want an injection of particle with the diameter of nozzle-hole, then with "point injection" the particle diameter should be the same of diameter point, that i set 0.00014 m.

I can't undertand why there are particle with diameter that is 0.00025m!

Can you help me?

thank you!!

Dear DrFloyd,

Where did you set the diameter and how did you get the particle diameter in fluent?

DrFloyd February 12, 2015 11:55

Dr fishball,
I apologize for the late reply but i was abroad.
In the discrete phase model i create an injection and i choose respectly:
injection type -> solid cone
diameter distribution -> uniform
point properties -> diameter = 1.4e-04.

Can you help me with these large bubbles that i find in the spray with a diameter bigger than the fixed size?
thank you!

fishball February 12, 2015 20:31

Quote:

Originally Posted by DrFloyd (Post 531607)
Dr fishball,
I apologize for the late reply but i was abroad.
In the discrete phase model i create an injection and i choose respectly:
injection type -> solid cone
diameter distribution -> uniform
point properties -> diameter = 1.4e-04.

Can you help me with these large bubbles that i find in the spray with a diameter bigger than the fixed size?
thank you!

Where you find the bigger diameter size from?

DrFloyd February 13, 2015 09:33

Hi fishball,
during the injection at some time the nozzle injects these large bubbles. I find them in a random position respect to spray axes at the end of the injection time. They are about 15-20!

fishball February 16, 2015 21:08

Quote:

Originally Posted by DrFloyd (Post 531732)
Hi fishball,
during the injection at some time the nozzle injects these large bubbles. I find them in a random position respect to spray axes at the end of the injection time. They are about 15-20!

Which injection type you set for the injection. For some atomizer types, only injector inner diameter could be configured not particle's diameter

DrFloyd February 17, 2015 03:05

Quote:

Originally Posted by fishball (Post 532106)
Which injection type you set for the injection. For some atomizer types, only injector inner diameter could be configured not particle's diameter

the injection type is "solid-cone"..I mean the initial diameter setted in "initial diameter distribution". This is the diameter of the first particles injected before the breakup and their size should be constant.

edoan February 17, 2015 14:22

is collision and coalescence turned off?

DrFloyd February 17, 2015 15:45

Quote:

Originally Posted by edoan (Post 532204)
is collision and coalescence turned off?

yes collision and coalescence are turned off


All times are GMT -4. The time now is 08:42.