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Basic notions and definitions
Before getting into the world of thermodynamics, we need to understand some basic notions and definitions.

■ System

  • The thermodynamic system is any portion of space or materials defined for study. A system can be open or closed.
    1. Open system: can exchange materials with surrounding
    2. Closed system: does not exchange materials with surrounding
    ※ Isolated system: does not exchange materials and energy with surrounding

■ Parameters

  • The parameters are either extensive or intensive depending on whether they depend on the mass of the system.
    1. Intensive parameters: the value does not depend on the volume(size) of system.
       ex) density, temperature, pressure etc.
    2. Extensive parameters: depend on the size of system.
       ex) volume, mass, energy, entropy etc.

■ Others

  1. Adiabatic: No heat transfer bewettn system and surrounding
  2. Diathermal: Heat can pass through

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Thermodynamics in Energy Engineering

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