{"id":159227,"date":"2021-06-07T08:25:15","date_gmt":"2021-06-07T08:25:15","guid":{"rendered":"\/forum\/forums\/topic\/fluent-dpm-unsteady-injection-file-how-does-repeat-interval-in-file-work\/"},"modified":"2021-06-08T14:40:55","modified_gmt":"2021-06-08T14:40:55","slug":"fluent-dpm-unsteady-injection-file-how-does-repeat-interval-in-file-work","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/fluent-dpm-unsteady-injection-file-how-does-repeat-interval-in-file-work\/","title":{"rendered":"Fluent DPM Unsteady Injection File: how does “Repeat Interval in File” work?"},"content":{"rendered":"
\n
\n

Hello everybody<\/p>\n

I am simulating a very simple case to verify the unsteady injection file characteristics (later to be applied to a more complex scenario). This test case consists of a number of hexa elements placed in series along the main axis, where the eulerian phase equation are disabled and only the lagrangian phase is solved. The inlet and the outlet sections of the domain are treated as periodicity, the lateral sides as simmetry. At a certain time, I am injecting a particle parcel in the domain, with an assigned velocity, diameter, parcel-mass, etc., where the only velocity component that is assigned is the one along the main axis (other are set to 0). Considering all this settings, parcels are injected in the domain and therefore remain there (they cannot escape, being trapped, evaporate…). The simulation is transient, with a dt=1e-4s and flow is inviscid.<\/p>\n

I am using this very simple unsteady injection file:<\/p>\n

(z=4 13)<\/p>\n

(x y z u v w diameter t parcel-mass mass n-in-parcel time flow-time)<\/p>\n

((0.0 0.00000000 5.5e-02 0.0 0.0 1 3.73e-05 400.0 1e-11 2.12406e-11 0.56349 0.0000e+00 2.0000e-04) injection-0:0)<\/p>\n

At this point, if I am using the "Repeat Interval in File" in the injection panel set to 0, the injection works fine: the parcel is injected at flow-time=0.0002 s, that is the prescribed time. Then I impose "Repeat Interval in File=10e-04s" and if I am not wrong I should expect that the injection file is re-winded once the periodic window (defined by the repeat interval time) is reached. For this unsteady file injection and this specif interval I should expect that considering a total simulation windows of 20e-4 s means two parcels in the domain (injected at 2e-04s and 12e-4s): instead three parcels are tracked…<\/p>\n

Of course I cleared the previous parcels before the test, as well I set to 0 the flow-time. <\/p>\n

I report also the "unexpected injection" according to the console:<\/p>\n

[…<\/p>\n

Updating solution at time level N…<\/p>\n

done.<\/p>\n

Advancing DPM injections ….<\/p>\n

number tracked = 1, escaped = 0, aborted = 0, trapped = 0, evaporated = 0, incomplete = 0, incomplete_parallel = 0<\/p>\n

iter time\/iter<\/p>\n

Flow time = 0.0011s, time step = 11<\/p>\n

9 more time steps<\/p>\n

Updating solution at time level N…<\/p>\n

done.<\/p>\n

Injecting 1 particle parcels with mass 1e-11 at t = 0.0011<\/p>\n

Advancing DPM injections ….<\/p>\n

number tracked = 2, escaped = 0, aborted = 0, trapped = 0, evaporated = 0, incomplete = 0, incomplete_parallel = 0<\/p>\n

iter time\/iter<\/p>\n

Flow time = 0.0012s, time step = 12<\/p>\n

8 more time steps<\/p>\n

Updating solution at time level N…<\/p>\n

done.<\/p>\n

Injecting 1 particle parcels with mass 1e-11 at t = 0.0012<\/p>\n

Advancing DPM injections ….<\/p>\n

number tracked = 3, escaped = 0, aborted = 0, trapped = 0, evaporated = 0, incomplete = 0, incomplete_parallel = 0<\/p>\n

iter time\/iter<\/p>\n

Flow time = 0.0013s, time step = 13<\/p>\n

..]<\/p>\n

As you can see, the test case is really fundamental and I think I am doing a very dumb error, but I cannot see where it is.<\/p>\n

Thanks in advance for any help!<\/p>\n","protected":false},"template":"","class_list":["post-159227","topic","type-topic","status-closed","hentry","topic-tag-ansys-fluent","topic-tag-dpm","topic-tag-fluid-dynamics","topic-tag-unsteady-tracking"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_author_ip":[""],"_bbp_old_reply_author_name_id":["Anonymous"],"_bbp_old_is_reply_anonymous_id":["false"],"_btv_view_count":["2716"],"_bbp_likes_count":["0"],"_bbp_subscription":["239915","139858"],"_bbp_topic_status":["unanswered"],"_bbp_status":["publish"],"_bbp_topic_id":["159227"],"_bbp_forum_id":["27792"],"_bbp_engagement":["22555","139858","200977"],"_bbp_voice_count":["3"],"_bbp_reply_count":["8"],"_bbp_last_reply_id":["277007"],"_bbp_last_active_id":["277007"],"_bbp_last_active_time":["2023-03-29 13:02:07"]},"test":"leonardo-langoneunifi-it"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/159227","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics"}],"about":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/types\/topic"}],"version-history":[{"count":0,"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/159227\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=159227"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}