Ch 6. Entropy Multimedia Engineering Thermodynamics Entropy Tds Relations EntropyChange IsentropicProcess IsentropicEfficiency EntropyBalance (1) EntropyBalance (2) ReversibleWork
 Chapter 1. Basics 2. Pure Substances 3. First Law 4. Energy Analysis 5. Second Law 6. Entropy 7. Exergy Analysis 8. Gas Power Cyc 9. Brayton Cycle 10. Rankine Cycle Appendix Basic Math Units Thermo Tables Search eBooks Dynamics Fluids Math Mechanics Statics Thermodynamics Author(s): Meirong Huang Kurt Gramoll ©Kurt Gramoll

 THERMODYNAMICS - CASE STUDY Introduction Problem Graphic Pat is taking a thermodynamics course this semester and in the class, his professor states that person increase entropy every time they do anything in daily life. Pat's mom cook eggs for his breakfast. He wonders how much entropy is generated when eggs are cooked. What is known: 6-cm-diameter spherical egg at 10oC is dropped into boiling water. The boiling water temperature is 100oC. Egg has a density of 1000 kg/m3 and a specific heat of 3.4 kJ/(kg-K). Question How much entropy is generated by boiling one egg to 100oC? Approach Method A: Take the egg as a system. It is a closed system due to no mass transfer involved. The entropy transfer is only due to the heat transfer. Model the egg as incompressible, and the entropy change in the system is ΔS = mCaveln(T2/T1) where 1 denotes the initial state and 2 denotes the final state. Method B: take the egg as a closed system. Consider the entropy change of the isolated system formed by the egg and the surrounding water.