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AREN 2110: WATER PROPERTIES. STATE INFORMATION FOR LIQUID , SATURATED LIQUID-SATURATED VAPOR PHASE MIXTURES , AND SUPERHEATED STEAM P-v AND T-v DIAGRAMS SATURATED LIQUID-VAPOR AND STEAM TABLE EXAMPLES.
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AREN 2110: WATER PROPERTIES • STATE INFORMATION FOR LIQUID, SATURATED LIQUID-SATURATED VAPOR PHASE MIXTURES, AND SUPERHEATED STEAM • P-v AND T-v DIAGRAMS • SATURATED LIQUID-VAPOR AND STEAM TABLE EXAMPLES
Phase Equilibrium Conditions and Associated Temperature Points (Drawn volumes are not to scale) SAT. ICE + SAT WATER ICE LIQUID WATER Q Q Q T = Ti = ice point SUPER-HEATED STEAM SAT. STEAM SAT. STEAM SAT. LIQUID SAT. LIQUID Q Q Q Q T > TS T = TS T = TS = boiling point T = TS
Q Q Q Q STATE 1: PURE LIQUID H2O; T = 20 C P = 1 ATM "COMPRESSED LIQUID" Add heat, T increases. P held constant by piston + air weight, DV > 0 STATE 2: PURE LIQUID H2O; T = 100 C P = 1 ATM "SATURATED LIQUID" IF any heat added, liquid vaporizes. P constant, DV > 0 STATE 3: 2-PHASE MIXTURE T = 100 C P = 1 ATM "SATURATED LIQUID-VAPOR MIXTURE" Add heat, more liquid vapor, DT = 0, DV > 0 STATE 4: ALL H20-VAPOR T = 100 C P = 1 ATM "SATURATED VAPOR" IF any heat lost, vapor will condense (DT = 0, DV < 0). If heat added, DT > 0, DV > 0. STATE 5: ALL H20-VAPOR T = 200 C P = 1 ATM "SUPERHEATED VAPOR" IF some heat lost, but T > 100 C, no condensation, DT < 0, DV < 0. IF heat added, DT > 0, DV > 0 Q LIQUID-VAPOR PHASES UNDER CONSTANT PRESSURE WITH HEAT ADDED FOR LIQUID TEMP INCREASE, BOILING, AND STEAM TEMP INCREASE; PISTON MAINTAINS PRESSURE AT 1 ATM FOR ALL STEPS.
PLOT MULTIPLE ISOBARIC PHASE CHANGE T-v LINES TO PRODUCE COMPLETE LIQUID WATER-STEAM T-v DIAGRAM FOR H2O
Q Q STATE 1: PURE LIQUID H2O; T = 150 C P = 1 MPa (~ 100 atm) "COMPRESSED LIQUID" Lower pressure (decrease piston W), T held constant, Dv > 0 STATE 2: PURE LIQUID H2O; T = 150 C P = Psat = 0.4758 MPa "SATURATED LIQUID" Liquid begins to boil. DP = 0, Dv > 0, (expands, DW = 0) STATE 3: 2-PHASE MIXTURE T = 150 C P = Psat = 0.4758 MPa "SATURATED LIQUID-VAPOR MIXTURE" Boils, expands, DT = 0, DP = 0, Dv > 0 (DW = 0) STATE 4: ALL SATURATED H20-VAPOR T = 150 C P = Psat = 0.4758 MPa "SATURATED VAPOR" IF any expansion and DT = 0, Dv > 0, DP < 0 (DW < 0); IF Dv < 0, condensation, DP = 0, DT = 0 PHASE CHANGE UNDER CONSTANT TEMPERATURE. FOR 1-PHASE, PRESSURE REDUCED BY LOWERING PISTON WEIGHT; HEAT ADDED TO MAINTAIN ISOTHERMAL CONDITION AS SPECIFIC VOLUME INCREASES AT EACH STEP. DURING BOILING P AND T ARE CONSTANT. Q STATE 5: SUPERHEATED STEAM T = 150 C P = 0.2 MPa "SUPERHEATED VAPOR" no condensation if P increased but < 0.4758 MPa, DT = 0, IF DP < 0, Dv > 0
PLOT MULTIPLE ISOTHERMAL PHASE CHANGE P-v LINES TO PRODUCE COMPLETE LIQUID WATER-STEAM P-v DIAGRAM FOR H2O