Inscrição na biblioteca: Guest

ISSN Online: 2377-424X

ISBN Print: 978-1-56700-421-2

International Heat Transfer Conference 15
August, 10-15, 2014, Kyoto, Japan

Modelling Heat and Mass Transfer in Porous Material during Pyrolysis using Operator Splitting and Dimensionless Analysis

Get access (open in a dialog) DOI: 10.1615/IHTC15.pmd.008848
pages 6883-6897

Resumo

Dimensionless analysis is used to improve the computational performance when using operator splitting methods to model the heat and mass transfer during pyrolysis. The specific examples investigated are thermal decomposition of polymer composite when used as heat shields during space-craft re-entry or for rocket nozzle’s protection, and the In-Situ Upgrading (ISU) of solid oil shale by subsurface pyrolysis to form liquid oil and . ISU is a very challenging process to model numerically because a large number of components need to be modelled using a system of equations that are both highly non-linear and strongly coupled. Inspectional Analysis is used to determine the minimum number of dimensionless groups that can be used to describe the process. This set of dimensionless numbers is then reduced to those that are key to describing the system behaviour. This is achieved by performing a sensitivity study using Experimental Design to rank the numbers in terms of their impact on system behaviour. The numbers are then sub-divided into those of primary importance, secondary importance and those which are insignificant based on the t-value of their effect, which is compared to the Bonferroni corrected t-limit and Lenth’s margin of error. Finally we use the sub-set of the most significant numbers to improve the stability and performance when numerically modelling this process. A range of operator splitting techniques is evaluated including the Sequential Split Operator (SSO), the Iterative Split Operator (ISO) and the Alternating Split Operator (ASO).