Peculiarities of the local abnormal heat transfer due to non-linear heat conductivity and their influence on the steam (gas) non-isothermal filtration through the particles layer
2010 (English)In: Applied Computer Sciences, 2010, 179-184 p.Conference paper (Refereed)
The 2-D model of a non-stationary, non-isothermal steam (gas) filtration through a monospherical particle layer with internal heat generation is considered and analyzed with the particular emphasis on the non-thermal steam/particles local equilibrium. The real non-linear properties of the steam (gas) and particles, as well as the influence of the impermeable medium surrounding the permable layer are taken into account. Boundary-value problem for the complex multiphase system of the steam (gas) flow and the layer of particles is formulated both in the dimension and then in dimensionless forms and both are discussed. The thermal hydraulic problem is solved numerically using the effective finite-difference fractional time-step method earlier develod by one of the authors. It is shown that some initial thermodynamic perturbations in the system, which are always present in such kind of systems, may cause the phenomenon of local abnormal steam heating (mainly due to non-linear heat conductivity of the steam having power-law character by temperature). This phenomenon was first revealed for such non-linear boundary-value problems in a modeling of geothermal systems 25 years ago. Then it was revealed for the severe accidents scenario both theoretically and experimentally. The phenomenon of local abnormal heating may cause some temperature escalation in a specific spatial region of the system, which is of paramount interest for many modern industrial and natural processes because it differs dramatically from the linear case, which is conventionally considered in a similar systems without taking into account the real non-linear processes.
Place, publisher, year, edition, pages
2010. 179-184 p.
, International Conference on Applied Computer Science - Proceedings, ISSN 1792-4863
Filtration, Localization of heating, Modelling, Non-linear conductivity, Partice layer, Steam
IdentifiersURN: urn:nbn:se:kth:diva-150301ScopusID: 2-s2.0-79959940704OAI: oai:DiVA.org:kth-150301DiVA: diva2:742740
International Conference on Applied Computer Science, ACS, 15 September 2010 through 17 September 2010, Malta
QC 201409022014-09-022014-09-012014-09-02Bibliographically approved