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Scaling Methods for Dynamic Building System Simulation in an HVACSIM+ Environment



Zhelun Chen, Jin Wen, Anthony J. Kearsley, Amanda Pertzborn


A robust and efficient nonlinear algebraic and differential equations solver is increasingly essential as the scale of dynamic building system simulation grows larger and the models employed become more complex. There are many factors affecting the performance of these solvers. In this paper the impact of variable scaling on the convergence of a family of Newton-method based solvers is summarized. A comparison of the performance of a few different scaling methods is presented using HVACSIM+, a software simulation tool that employs Powell's Hybrid method to solve the system of nonlinear algebraic equations. A small commercial building is modelled in HVACSIM+ and serves as an illustrative example for this study. It is demonstrated that, for these methods, variable scaling can strongly influence computational performance but, for our example problem, any improvement or deterioration in numerical accuracy is limited. The conclusions are not limited to the software platform HVACSIM+.
Proceedings Title
Proceedings of the 15th IBPSA Conference
Conference Dates
August 7-9, 2017
Conference Location
San Francisco, CA, US
Conference Title
Building Simulation 2017


HVAC, HVACSIM+, building simulation, Newton's Method, Scaling, Powell's Hybrid Method


Chen, Z. , Wen, J. , Kearsley, A. and Pertzborn, A. (2017), Scaling Methods for Dynamic Building System Simulation in an HVACSIM+ Environment, Proceedings of the 15th IBPSA Conference, San Francisco, CA, US, [online], (Accessed July 15, 2024)


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Created August 9, 2017, Updated September 28, 2022