Computation of Air Flow in CMU’s Intelligent Workplace and Its Effect on Occupant Health and Comfort

In this paper, computational fluid dynamics (CFD) is utilized to investigate thermal comfort and energy efficiency of an office in the Intelligent Workplace (IW) of Carnegie Mellon University. First, a comprehensive geometric grid model is constructed to represent the office including the walls, floor, roof, windows, doors, fan coil units, and furnishings. Then the air flow and accompanying heat exchange with the bounding surfaces of the office are calculated based on indoor and outdoor ambient conditions, the operating conditions of the fan coil units and windows, and the occupancy of the space. The computational results of the air flow provide the means to measure whether comfort conditions have been established based on the outside conditions and on the operation of the fan coil units. The operating conditions of the fan coil units, fan speed, and chilled/heated water flow, determine their effectiveness in cooling/heating and their operating costs. This CFD air flow simulation, therefore, when generalized, provides a design support system for architects and engineers. The numerical solutions of office space are calibrated and validated by empirical operational data from the fan coil units. The design support system will enable the evaluation of the annual performance and operating cost of given fan coil units in a given building space.