کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
649084 884642 2009 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Simulation of dynamics and control of a double-effect LiBr-H2O absorption chiller
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی جریان سیال و فرایندهای انتقال
پیش نمایش صفحه اول مقاله
Simulation of dynamics and control of a double-effect LiBr-H2O absorption chiller
چکیده انگلیسی
A dynamic model has been developed to simulate dynamic operation of a real double-effect absorption chiller. Dynamic behavior of working fluids in main components was modeled in first-order nonlinear differential equations based on heat and mass balances. Mass transport mechanisms among the main components were modeled by valve throttling, 'U' tube overflow and solution sub-cooling. The nonlinear dynamic equations coupled with the subroutines to calculate thermodynamic properties of working fluids were solved by a numerical method. The dynamic performance of the model was compared with the test data of a commercial medium chiller. The model showed a good agreement with the test data except for the first 83 min during which different flow rates of the weak solution caused some discrepancy. It was found that the chiller dynamics is governed by the inlet temperatures of the cooling water and the chilled water when the heat input to the chiller is relatively constant. For a step change of load at constant inlet temperatures of the cooling water and the chilled water, the response time of the chilled water exit temperature was about 15 min and it was due to the thermal capacities of the chiller. The dilution cycle was found to be an essential means for improvement of control performance as well as anti-crystallization.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Applied Thermal Engineering - Volume 29, Issue 13, September 2009, Pages 2718-2725
نویسندگان
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