Determining critical conditions for two dimensional compost piles with air flow via numerical simulations

Thiansiri Luangwilai, Harvinder Sidhu


We consider the self-heating process of a two dimensional, spatially dependent, model of a compost pile which incorporates terms that account for self-heating due to both biological and oxidative mechanisms. This self-heating model consists of mass balance equations for oxygen and energy. We study the effects of air flow through the pile. Numerical solutions determine critical conditions for thermal ignition within the compost pile. Two distinct numerical approaches corroborate solutions to the self-heating problem in compost piles. We analyse the model numerically using FlexPDE (a commercial software package) in a two dimensional configuration. The results obtained are then compared with those obtained using the Method of Lines. We focus mainly on the critical conditions for thermal ignition for different rates of air flow moving through the compost pile.

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biological self-heating; compost pile; air-flow;

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