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Thermo cht 3
Term | Definition |
---|---|
Simple Compressible Substance | a substance whose magnetic effects and electrical effects are insignificant but changes in volume are very important For example water or a uniform mixture of non-reacting gases). |
Simple Compressible System | a system consisting of a simple compressible substance |
State Principle | The state of a simple compressible system at equilibrium can be uniquely determined by two independent intensive thermodynamic properties |
Single-phase regions | solid, liquid, vapor |
Two-phase regions | liquid-vapor (vaporization & liquefaction) solid-liquid (melting & freezing) solid-vapor (sublimation: gasification and solidification) |
vaporization & liquefaction | liquid-vapor |
melting & freezing | solid-liquid |
sublimation: gasification and solidification | solid-vapor |
Triple line | the line along which three phases can exist in equilibrium |
Critical point | the point for the maximum temperature and pressure at which liquid and vapor phases can coexist in equilibrium. |
Triple point | a point of the triple line projected onto the phase diagram |
isotherms | constant-temperature lines drawn in p -v diagram |
isobars | Note the constant-pressure lines |
Saturation temperature | the temperature at which a phase change takes place at a fixed pressure |
Saturation pressure | the pressure at which a phase change takes place at a fixed temperature |
Subcooled liquid (compressed liquid) | the liquid of which temperature is lower than the saturation temperature |
Saturated liquid | a substance that exists as liquid at the saturation condition |
Quality (x) | the ratio of the mass of vapor present to the total mass of the liquid-vapor mixture - an intensive property |
Saturated vapor | a substance that exists as vapor at the saturation condition |
dry saturated vapor | quality is 1. |
Superheated vapor | a vapor of which temperature is higher than the saturation temperature |
supercritical fluid | If the pressure is equal to or higher than pc |
Specific Heats | → intensive properties; also called heat capacities) |
thermally perfect | When u and h of a gas are functions of temperature only |
calorically perfect | when Cv and Cp are constant monatomic gases or other gases with small temperature change |
isobaric process | p = constant |
isometric process | Volume is constant |