Hi,<\/p>\n
<\/p>\n
<\/p>\n
<\/p>\n
I have been modeling piezoelectric acoustic transducers to determine the frequency response spectrum in water.<\/p>\n
<\/p>\n
<\/p>\n
<\/p>\n
The specific transducer types I am modeling are monopole ring and dipole bender bar transducers. They are to be operated in a pulse mode: a single sine differential voltage pulse is applied. The frequencies I am modeling are between 500 Hz and 20 kHz.<\/p>\n
<\/p>\n
<\/p>\n
<\/p>\n
I have been using a harmonic analysis in workbench 19.1 with both the acoustic and piezoelectric extensions. Materials are modeled as isotropic as a simplification.<\/p>\n
<\/p>\n
<\/p>\n
<\/p>\n
My models (for both ring and bender transducers) all suffer from the same issues:<\/p>\n
<\/p>\n
<\/p>\n
<\/p>\n
(1) The model shows a much higher response than the experiment at resonance<\/p>\n
<\/p>\n
(2) The model shows a lower response than the experiment at both higher and lower frequencies than resonance<\/p>\n
<\/p>\n
(3) The location of the peaks in the model vs. experiment is substantially different<\/p>\n
<\/p>\n
(4) Typically the difference in response for the model between two designs is much greater than reality<\/p>\n
<\/p>\n
<\/p>\n
<\/p>\n
I have attached the response of two different ring transducers for the model vs. experiment to illustrate the problem.<\/p>\n
<\/p>\n
<\/p>\n
<\/p>\n
What’s wrong and what could be used to improve the fidelity of the model (and be able to use it to predict the behavior of the actual part)?<\/p>\n
<\/p>\n
<\/p>\n
<\/p>\n
Much higher mesh densities?<\/p>\n
<\/p>\n
Adding damping to the transducer? If so what is the best method?<\/p>\n
<\/p>\n
Modeling via fluent rather the acoustic extension?<\/p>\n
<\/p>\n
Doing a transient analysis rather than a harmonic analysis to more closely match the experiment?<\/p>\n
<\/p>\n
Or am I expecting too much from this type of model?<\/p>\n
<\/p>\n
<\/p>\n
<\/p>\n
Any help or insights would be much appreciated as I have very little experience with Ansys and acoustic\/piezoelectric modeling and don’t know where to start.<\/p>\n
<\/p>\n
<\/p>\n
<\/p>\n
Thanks,<\/p>\n
<\/p>\n
<\/p>\n
<\/p>\n
Raphael<\/p>\n","protected":false},"template":"","class_list":["post-29557","topic","type-topic","status-closed","hentry"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_old_topic_id":["1726"],"_bbp_old_topic_author_name_id":["Anonymous"],"_bbp_old_is_topic_anonymous_id":["false"],"_bbp_old_closed_status_id":["publish"],"_bbp_author_ip":[null],"_bbp_old_sticky_status_id":["normal"],"_bbp_likes_count":["0","0","0","0","0"],"_btv_view_count":["978"],"_bbp_topic_status":["unanswered"],"_bbp_status":["publish"],"_bbp_topic_id":["29557"],"_bbp_forum_id":["27791"],"_bbp_engagement":["240","157368"],"_bbp_voice_count":["2"],"_bbp_reply_count":["3"],"_bbp_last_reply_id":["59797"],"_bbp_last_active_id":["59797"],"_bbp_last_active_time":["2018-06-25 23:55:01"]},"test":"raphaelr"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/29557","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\/29557\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=29557"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}