Use this identifier to quote or link this document: http://hdl.handle.net/2072/169270

Improving the accuracy of heat balance integral methods applied to thermal problems with time dependent boundary conditions
Mitchell, Sarah L.; Myers, T.G.
Centre de Recerca Matemàtica
In this paper the two main drawbacks of the heat balance integral methods are examined. Firstly we investigate the choice of approximating function. For a standard polynomial form it is shown that combining the Heat Balance and Refined Integral methods to determine the power of the highest order term will either lead to the same, or more often, greatly improved accuracy on standard methods. Secondly we examine thermal problems with a time-dependent boundary condition. In doing so we develop a logarithmic approximating function. This new function allows us to model moving peaks in the temperature profile, a feature that previous heat balance methods cannot capture. If the boundary temperature varies so that at some time t & 0 it equals the far-field temperature, then standard methods predict that the temperature is everywhere at this constant value. The new method predicts the correct behaviour. It is also shown that this function provides even more accurate results, when coupled with the new CIM, than the polynomial profile. Analysis primarily focuses on a specified constant boundary temperature and is then extended to constant flux, Newton cooling and time dependent boundary conditions.
2011
53 - Física
Calor -- Transmissió
Dinàmica de fluids
Aquest document està subjecte a una llicència d'ús de Creative Commons, amb la qual es permet copiar, distribuir i comunicar públicament l'obra sempre que se'n citin l'autor original, la universitat i el centre i no se'n faci cap ús comercial ni obra derivada, tal com queda estipulat en la llicència d'ús (http://creativecommons.org/licenses/by-nc-nd/2.5/es/)
Preprint
Centre de Recerca Matemàtica
Prepublicacions del Centre de Recerca Matemàtica;1013
         

Full text files in this document

Files Size Format
Pr1013.pdf 316.7 KB PDF

Show full item record

 

Coordination

 

Supporters