Objectives Discuss HW5 – Plumbing Finalize valve design Learn about boilers Discuss power generation

HW5: Find a system curve for this plumbing configuration 40 ft 20 ft 20 ft Due date: May 5th 5 ft 200 ft 30 ft 30 ft 200 ft 40 ft 10 ton 30 ft 20 ft 10 ft 5 ft 5 ft 10 ft 10 ft 5 ft 30 ft 10 ft 5 ft 5 ft 10 ton HW5 – Design

Valve Sizing and Flow Coefficient Cv value: in liter/hour or…. in Pa Control Valve Selection For Hydronic Systems reference: http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0CCUQFjAA&url=http%3A%2F%2Fbookstore.ashrae.biz%2Fjournal%2Fdownload.php%3Ffile%3Dhegberg.pdf&ei=IvcqU_O1KMuE2AWgloHgDA&usg=AFQjCNFRAMzPnbzDpAluhyk4l8u_SKKTdw

Control Valve Selection For Hydronic Systems Before Digital Control we tried to do this Valve authority

Combined heat and power (cogeneration CHP or three generation CCHP) Here, we use thermal energy for heating and/or cooling

Power generation in steam turbines (Rankine cycle) Pump Nuclear Coal

Ideal Rankine Cycle 1-2 isentropic pump 2-3 constant pressure heat addition 3-4 isentropic turbine 4-1 constant pressure heat rejection

Ideal Rankine Cycle h1=hf saturated liquid Wpump (ideal)=h2-h1=vf(Phigh-Plow) vf=specific volume of saturated liquid at low pressure qin=h3-h2 heat added in boiler Usually either qin will be specified or else the high temperature and pressure (so you can find h3) qout=h4-h1 heat removed from condenser) wturbine=h3-h4 turbine work

Deviations from Ideal in Real Cycles Pump is not ideal Turbine is not ideal There is a pressure drop across the boiler and condenser We need to sub-cool the liquid in the condenser to prevent cavitation in the pump.

Reheat Cycle It allows increase boiler pressure without problems of low quality at turbine exit

Coal Boiler

Coal burning method Long time ago: Today: 1) Fluidized bed: http://www.youtube.com/watch?v=8n78CDI3GoU 2) Powdered coal: http://www.youtube.com/watch?v=g1ojza-nbqs

Coal-fired power plant filters For Particulate Maters Electrostatic precipitator Filter bags Scrubber for SO2 (to prevent formation of Sulfuric acid – H2SO4) Grinded Limestone in water (slurry) sprayed into the gas fluid stream SO2 + Limestone slurry → Gypsum (used for wallboard)

Oil – Gas based boilers Gas circulate through tubes water is in-between Water tube boiler

Furnaces For homes Roof tops and induct heaters