Efficient Low-Lift Cooling with Radiant Distribution, Thermal Storage, and Variable-Speed Chiller Controls—Part I: Component and Subsystem Models

Component and subsystem models used to evaluate the performance of a low-lift cooling system are described. An air-cooled chiller, a hydronic radiant distribution system, variable-speed control, and peak-shifting controls are modeled. A variable-speed compressor that operates over 20:1 speed range and pressure ratios ranging from one to six is at the heart of the chiller. Condenser fan and chilled-water pump motors have independent speed controls. The load-side distribution is modeled from the refrigerant side of the evaporator to the conditioned zone as a single subsystem controlled by chilled-water flow rate for a specified instantaneous cooling load. Performance of the same chiller when operating with an all-air distribution system is also modeled. The compressor, condenser fan, and chilled-water pump motor speeds that achieve maximum coefficient of performance (COP) at a given condition are solved at each point on a grid of load and outdoor temperature. A variable-speed dehumidification subsystem is modeled and simulated as part of a dedicated outdoor air system to condition the ventilation air. A companion paper evaluates the annual cooling system energy use and potential energy savings to be gained by integrating radiant cooling, cool storage, and variable-speed compressor and transport motor controls.

[1]  Moncef Krarti,et al.  The impact of forecasting uncertainty on the performance of a predictive optimal controller for thermal energy storage systems , 1999 .

[2]  SystemsGregor,et al.  Development of a Predictive Optimal Controller for Thermal EnergyStorage , 1996 .

[3]  E. Granryd.  Power for Fans and Pumps in Heat Exchangers of Refrigerating Plants , 1998 .

[4]  Gunnar Stiesch.  PERFORMANCE OF ROTARY ENTHALPY EXCHANGERS , 1994 .

[5]  Srinivas Katipamula,et al.  Efficient Low-Lift Cooling with Radiant Distribution, Thermal Storage, and Variable-Speed Chiller Controls—Part II: Annual Use and Energy Savings , 2009 .

[6]  Sanford Klein,et al.  Methodologies for optimal control of chilled water systems without storage , 1989 .

[7]  Stanley A. Mumma,et al.  Ceiling Radiant Cooling Panels as a Viable Distributed Parallel Sensible Cooling Technology Integrated with Dedicated Outdoor Air Systems , 2001 .

[8]  Yasuyuki Fujimura.  Dehumidification of air , 1998 .

[9]  P. Jacobs,et al.  State-of-the-Art Review Whole Building, Building Envelope, and HVAC Component and System Simulation and Design Tools , 2002 .

[10]  L. Boeswirth,et al.  Simple but Efficient Methods for Estimation of Value Loss, Capacity Loss Due to Suction Valve Throttling and Heat Transfer in Cylinder , 1998 .

[11]  W. F. Stoecker,et al.  Refrigeration and air conditioning , 1958 .

[12]  Douglas T. Reindl,et al.  A Semi-Empirical Method for Representing Domestic Refrigerator/Freezer Compressor Calorimeter Test Data , 2000 .

[13]  Jeffrey D. Spitler,et al.  A Parameter Estimation Based Model of Water-to-Water Heat Pumps for Use in Energy Calculation Programs , 2002 .

[14]  J. Braun,et al.  Performance and control characteristics of a large cooling system , 1987 .

[15]  Barbara Pfeffer,et al.  Refrigeration and Air Conditioning , 1982 .

[16]  Moncef Krarti,et al.  Development of a Predictive Optimal Controller for Thermal Energy Storage Systems , 1997 .

[17]  W. K. Lewis,et al.  The Evaporation of a Liquid Into a Gas , 1922, Transactions of the American Society of Mechanical Engineers.

[18]  P. Popovic,et al.  A semi-empirical method for modeling a reciprocating compressor in refrigeration systems , 1995 .

[19]  M. McLinden,et al.  NIST Standard Reference Database 23: Reference Fluid Thermodynamic and Transport Properties-REFPROP, Version 8.0 , 2007 .

[20]  J. W. Ramsey,et al.  Thermal Environmental Engineering , 1970 .

[21]  Samuel F. Baldwin.  The Materials Revolution and Energy-Efficient Electric Motor Drive Systems , 1988 .

[22]  C. T. Gosling.  Applied Air Conditioning and Refrigeration , 1974 .

[23]  William A. Beckman,et al.  Models for variable-speed centrifugal chillers , 1987 .

[24]  Leon R. Glicksman,et al.  Improving heat pump performance via compressor capacity control: analysis and test. Volume II. Appendices , 1976 .