Modelica Based Dynamic Modeling of Water-Cooled Centrifugal Chillers
نویسندگان
چکیده
In this paper, the transient model of a water-cooled centrifugal chiller is developed in Modelica with Dymola and the TLK/IfT Library (TIL). The centrifugal compressor is modeled in detail based on the turbomachinery theory. The chiller capacity control is achieved by the combination of variable inlet guide vane (VIGV) and variable speed drive (VSD). The shell-and-tube heat exchangers are discretized based on the finite volume method with convenient and numerically efficient two-phase property evaluations. A thermal expansion valve (TXV) is used to regulate the pressure levels at the condenser and evaporator sides. These models are interconnected to form a centrifugal chiller system. The developed chiller model could be easily integrated to various control applications and it is proposed to validate the controller performance at the simulation phase prior to experimentation.
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