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A stiff variable time step transport solver for CONTAM



David M. Lorenzetti, William Stuart Dols, Andrew K. Persily, Michael D. Sohn


CONTAM, a multizone model for predicting whole-building airflow and contaminant transport, has been updated to improve the speed and accuracy of its transport calculations. CVODE, a general-purpose code for solving ordinary differential equations, brings variable time steps, high-order integration meth¬ods, and automatic error control to CONTAM. We describe the modeling decisions needed to integrate CVODE into CONTAM, then compare it to the original transport solvers on two realistic building models. CVODE can be more accurate when simulating fast transport mechanisms such as sorption, chemical re¬actions, or even high air change rates. In many cases, CVODE also runs faster than the legacy solvers— up to 180 times faster in the tests reported here.
Building and Environment


Keywords: contaminant, pollutant, transport, simulation, buildings, CONTAM, CVODE


Lorenzetti, D. , Dols, W. , Persily, A. and Sohn, M. (2013), A stiff variable time step transport solver for CONTAM, Building and Environment, [online], (Accessed April 20, 2024)
Created May 9, 2013, Updated October 12, 2021