'Centre for Evaluation in Education and Science (CEON/CEES)'
Doi
Abstract
U radu su prikazani rezultati numeričkih proračuna interakcije fluid-struktura korišćenjem diskretizacionih numeričkih metoda - metode konačnih elemenata za proračun naponsko-deformacionog stanja zida kanala i metode konačnih zapremina za numerički proračun dinamike fluida. Na osnovu dobijenih rezultata razvijen je fazi ekspertski sistem za procenu izlaznih parametara numeričkog proračuna, prikazane su osnovne karakteristike razvijenog fazi modela i rezultati dobijeni njegovom primenom. Analizirani su uticaji tri ulazna parametra - temperature unutrašnje površine zida kanala, razlike između temperatura unutrašnje i spoljašnje površine zida i faktora koji definiše gustinu numeričkih mreža - na dva izlazna parametra: vrednost pada statičkog pritiska niz struju i vrednost maksimalnih kombinovanih Fon Misesovih napona ostvarenih u strukturi kanala za zadate uslove opterećenja. Na osnovu dobijenih rezultata vidimo da formirani fazi ekspertski sistem može sa zadovoljavajućom tačnošću biti iskorišćen za procenu posmatranih izlaznih veličina, pri znatno kraćem vremenu potrebnom za proračun i uz angažovanje resursa računarskog sistema u značajno manjem obimu.This paper deal with structural deformation of one rectangular, closed, thin walled, steel made, thermally loaded channel and influence of this deformation on the air flow through the channel, recognised as coupled fluid-structure interaction problem. The geometrically non-linear deformation of thermally loaded channel was solved using commercial finite-element analysis software ANSYS. The unsteady Navier-Stokes equations in their conservation form defining fluid flow are solved using commercial computer fluid dynamics software ANSYS CFX. A fuzzy logic-based expert system has been developed to predict some results of structural and fluid flow numerical simulation instead of directly evaluating it by a time-consuming software coupling of finite-element and computer fluid dynamics numerical analysis. Three input parameters, namely temperature of channel inner walls, difference in temperature of inner and outer surface of channel wall, and factor of mesh size, are varied while solving the fluid-structure interaction problem. A pressure drop downstream the flow was considered as a computer fluid dynamics output parameter of importance, while Von Misses maximum stresses were an finite-element analysis output parameter observed. The developed FLES can predict the results of finite-element and computer fluid dynamics analysis, a pressure drop and Von Misses maximum stresses respectively, within a reasonable accuracy limit and at lower computation cost compared to the finite-element, and CFD computer fluid dynamics packages combined into series of multi-physics analyses
