پاورپوینت ENGSC 2333 – Thermodynamics Chapter 3

— پاورپوینت شامل تصاویر میباشد —-

اسلاید ۱ :

oTo apply the energy balance to a system of interest requires knowledge of the properties of the system and how the properties are related.  The objective of Chapter 3 is to introduce property relations relevant to engineering thermodynamics.  We will focus on the use of the closed system energy balance introduce in Chapter 2, together with the property relations considered in this chapter.

اسلاید ۲ :

Some Concepts and Definitions

oState principal

oSimple compressible system

op-υ-T surface

o2-phase region

oTriple line

oTriple point

oSaturation state

oVapor dome

o

oCritical point

op-υ diagram

oT-υ diagram

oSubcooled (compressed) liquid

oSuperheated vapor

o2-phase liquid-vapor mixture

oQuality

اسلاید ۳ :

For simple, compressible systems, the state principle indicates that the number of independent intensive properties is two.

Intensive properties such as velocity and elevation that are assigned values relative to datum outside the system are excluded from present considerations.

اسلاید ۴ :

For a two-phase liquid-vapor mixture, the ratio of the mass of vapor to the total mass of the mixture is call quality, represented as x.

اسلاید ۵ :

The specific volume of a two-phase liquid-vapor mixture can be determined by using the saturation tables and the definition of quality.

اسلاید ۶ :

In many thermodynamic analyses the sum of the internal energy U and the product of pressure p and volume V appears.  Because the sum U + pV appears so frequently, we give this combination a name, enthalpy, and a distinct symbol, H.