THE SECOND LAW OF THERMODYNAMICS - LECTURE - 9

THE SECOND LAW OF THERMODYNAMICS - LECTURE - 9 - STUDY MATERIAL

ENTROPY

The first law of thermodynamics deals with the property energy and the conservation of energy. The second law introduced in the previous chapter, leads to the definition of a new property called entropy.

Entropy is defined in terms of a calculus operation, and no direct physical picture of it can be given. In this chapter, Clausius inequality, which forms the basis for the definition of entropy will be discussed first.

It will be followed by the discussion of entropy changes that take place during various processes for different working fluids. Finally, the reversible steady-flow work and the isentropic efficiencies of various engineering devices such as turbine and compressors will be discussed.

AVAILABLE ENERGY, AVAILABILITY AND IRREVERSIBILITY

From second law of thermodynamics we found that complete conversion of heat into work is not possible in a continuous process. Also it has been proved that the most efficient cycle to produce work is a reversible power cycle (Carnot cycle).

Even in carnot cycle, the efficiency of conversion can never be unity and hence to establish a comparison of the work-energy conversion in actual processes, the maximum theoretical work obtainable with respect to some datum must be determined. This chapter is dedicated for this objective.

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UNIT-2 IInd Law of TD (Hand Written Notes) : https://www.file-upload.com/aq0vlmfyihur

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