240 likes | 389 Views
Objectives. Finish duct systems Learn about plumbing systems Discuss your question relate to HW4 Introduce some project topics. VAV Operation. How to use multiple pumps. Dampers. Summary of Air Distribution Systems. Select diffuser based on ADPI Given a layout of duct system
E N D
Objectives • Finish duct systems • Learn about plumbing systems • Discuss your question relate to HW4 • Introduce some project topics
Summary of Air Distribution Systems • Select diffuser based on ADPI • Given a layout of duct system • Calculate total pressure drop • Deal with non-circular ducts and fitting losses • Select the fan based on fan and duct curve
Hydronic Terms • Head loss • Open-loop vs. closed loop
Pumps • Driving force to move air water in buildings • Raise pressure and produce flow • One main type • Centrifugal
Pump curves • NPSHR = Net Positive Suction Head Required
Project • Design problem • …. • Research problem • ….
Couple chiller and cooling tower Cooling tower TCTS TCTR Weather parameters P - Find COP for several weather condition • Use nonlinear equation solution methods TCWS TCWR Q
HVAC Control Economizer (fresh air volume flow rate control) fresh air damper filter cooling coil heating coil filter steam humidifier fan mixing
Mixture 3 DPTSP Set Point (SP) Mixture 2 Mixture 1 DBTSP Sequence of operation(ECJ research facility) Control logic: Mixture in zone 1: IF (( TM<TSP) & (DPTM<DPTSP) ) heating and humidifying Heater control: IF (TSP>TSA) increase heating or IF (TSP<TSA) decrease heating Humidifier: IF (DPTSP>DPTSA) increase humidifying or IF (DPTSP<DPTSA) decrease humid. Mixture in zone 2: IF ((TM>TSP) & (DPTM<DPTSP) ) cooling and humidifying Cool. coil cont.: IF (TSP<TSA) increase cooling or IF (TSP>TSA) decrease cooling Humidifier: IF (DPTSP>DPTSA) increase humidifying or IF (DPTSP<DPTSA) decrease hum. Mixture in zone 3: IF ((DPTM>DPTSP) ) cooling/dehumidifying and reheatin Cool. coil cont.: IF (DPTSP>DPTSA) increase cooling or IF (DPTSP<DPTSA) decrease cooling Heater control: IF (TSP>TSA) increase heating or IF (TSP<TSA) decrease heating
Fan Biomedical Engineering (BME) Building Duct Optimization Ducts Supply Return In-Take air Exhaust
Life Cycle Cost Analysis • Engineering economics Option A Option B
VAV Example • One system • Multiple Spaces/Zones - VAV box for each space/zone • http://www.trane.com/commercial/library/vol242/v24b6.asp