Airflow Distribution and Microenvironment Evaluation of CMP Task Conditioning System

Microenvironment of a typical office workplace consisting computer monitor panel (CMP) task conditioning systems was studied by numerical simulation. Two CMP task conditioning systems were operated while a conventional HVAC system supplied air through a diffuser located in the ceiling. Air was exhausted through a ducted ceiling-level grill. Numerical simulation by k-ε 3-D turbulent model was conducted to study the influence of supply velocity on microenvironment of CMP task conditioning system. Three task conditioning velocities, 0.8, 1.0 and 1.2 m/s were studied Temperature and velocity distribution, Draught Rating (DR) and Predicted Percentage of Dissatisfied (PPD) of the room and workstation were studied. Results showed that room temperature was distributed by region, and occupant was exactly in supplying area. Temperature around occupant was apparently lower than surrounding temperature. So task conditioning had high air-supplying efficiency. Results also showed that task conditioning can provide excellent working environment when supply velocity were well designed. Task conditioning may cause draught according to conventional thermal comfort standard. When supply velocity is 1.0 or 1.2 m/s, DR around head reached 25 or 30 and PPD reached 12 or 15, so it may be uncomfortable to occupant. However occupant can control supply velocity and air blowing distance of task conditioning system to maintain acceptable thermal comfort. To summarize, flexible control of task conditioning system can create a more comfortable indoor environment.