Lecture Objectives: Learn about plumbing system and pumps Review the course topics and do the course evaluation

Water Cooled Chiller Loops Cooling tower loop Chiller water loop

Plumbing system Cooling towers

Relationship between velocity in a pipe and pressure drop Δp ~ v2 Δp = Constant × v2 Required power (P) for the pump P = V × Δp P –power [W], V –volume flow rate [m3/s], v – velocity [m/s] Δp – pressure drop [Pa] Δp ~ v2 (Δp ~ V2 – when same pipe is used) P ~ V × V2 – when same pipe is used P ~ V3 P2/P1 = (V2/V1)3 For the same pipe When different pipe is used for the same flow rate: For the same flow rate V Reduction of D: smaller pipe larger pipe Δp [Pa or ft water] D1 D2= D1/2 A1 V1 P1 A2=1/22 A1 V2=22 V1 P2/P1 = (D1/D2)4 - for the same flow rate or 50% smaller diameter of the pipe for the same flow rate wee have: 4 times larger velocity 16 times larger pressure drop and 16 times lager power for the pump v [m/s or fpm]

Examples of pump power P = V × Δp (all units metric) Sorption cooling Power generation 2 1

Head Loss

Fittings

System Curves ∆p ∆p A+B A B A+B A B V A B V A B Parallel Serial

Pumps Raise pressure and produce flow Main type Centrifugal Example of Turbine pump Base mounted Inline Reading (textbook) Page 3-36 - 3-45

Pump curves NPSHR = Net Positive Suction Head Required

Changing Pump Speed

Net Positive Suction Head (cavitation)

Curve for Multiple Pumps

System balancing AHU1 AHU2 HC1 HC2 100 ft 1000 ft 10 gpm 2 gpm 10 ft pump BOILER

Course Summary Course Objectives:   Learn about advanced building energy and environmental control systems. Obtain knowledge about district cooling and heating systems. Gain the skills and tools necessary to evaluate integration of sustainable energy production systems to a given building site. Study application of combined heat and power systems in a specific building or group of buildings. Conduct thermal, hydraulic and economic modeling of integrated building energy systems for planning and design. Course Topics:   Class intro and HVAC systems review Building ventilation heat recovery systems Thermal (solar and waste heat) powered desiccant systems 4. Centralized (compressor and sorption based) cooling systems 5. Centralized heating systems 6. District heating and cooling distribution systems 7. Geothermal buildings systems 8. Combined heat and power systems 9. Systems integration and control