2013-2-27 Basic concepts:System Classification Mass.M of both energy(heat and work) hea、g Basic concepts:System Classification 02013-2-27 18 1 2 4 3 Mass, M Work, W heat , Q 1 ⇒ Open System (Control volume)：between a system and surrounding, there are exchanges of both energy (heat and work) and mass 35 Basic concepts: System Classification 36 Basic concepts: System Classification