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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. Δ p ~ v 2
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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 × ΔpP –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)3For the same pipe • When different pipe is used for the same flow rate: • For the same • flow rate V • Reduction of D: D2= D1/2 A2=1/22 A1 V2=22 V1 A1 V1 P1 smaller pipe D1 larger pipe Δp [Pa or ft water] 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
Simple absorption system 3V 3L 3LLP
System Curves ∆p ∆p A+B A+B B A B A 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
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