Problems with particle injection with zero velocity

ECruz · August 7, 2019, 11:47

Hi everyone,

while using the icoUncoupledKinematicParcelFoam solver with injectionType patchInjection, I noticed some strange behaviour regarding particle initial velocity. Setting U0 to (0.0 0.0 0.0) in constant/kinematicCloudProperties had the same effect as initializing it as flow velocity. I'd like to know why this is happening and if it should happen.

Regards,

ECruz

dscian · August 7, 2019, 21:02

Colliding type parcels (DPMFoam and uncoupledKinematicParcelFoam) are not supposed to be injected with patchInjection as there might be a big overlap between particles initially which causes unrealistic behaviour. I believe setting inlet velocity to zero would make it even worse.

ECruz · August 8, 2019, 09:26

Even if I set collisionModel to none? The simulation is steady-state, by the way.

ECruz

dscian · August 9, 2019, 22:39

Without collisionModel it shouldn't be a problem. Could you share your kinematicCloudProperties file?

August 7, 2019, 11:47	Problems with particle injection with zero velocity	#1
ECruz New Member Eduardo Cruz Join Date: Oct 2018 Posts: 13 Rep Power: 7	Hi everyone, while using the icoUncoupledKinematicParcelFoam solver with injectionType patchInjection, I noticed some strange behaviour regarding particle initial velocity. Setting U0 to (0.0 0.0 0.0) in constant/kinematicCloudProperties had the same effect as initializing it as flow velocity. I'd like to know why this is happening and if it should happen. Regards, ECruz

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August 7, 2019, 21:02		#2
dscian Member Utkan Caliskan Join Date: Aug 2014 Posts: 42 Rep Power: 11	Colliding type parcels (DPMFoam and uncoupledKinematicParcelFoam) are not supposed to be injected with patchInjection as there might be a big overlap between particles initially which causes unrealistic behaviour. I believe setting inlet velocity to zero would make it even worse.

August 8, 2019, 09:26		#3
ECruz New Member Eduardo Cruz Join Date: Oct 2018 Posts: 13 Rep Power: 7	Even if I set collisionModel to none? The simulation is steady-state, by the way. ECruz

August 9, 2019, 22:39		#4
dscian Member Utkan Caliskan Join Date: Aug 2014 Posts: 42 Rep Power: 11	Without collisionModel it shouldn't be a problem. Could you share your kinematicCloudProperties file?