Thermodynamics Lecture Series Capturing the Lingo Assoc. Prof. Dr. Jaafar Jantan aka DR. JJ Applied Science Education Research Applied Science, UiTM, Shah Alam Journey towards Enrichment and Balance utilizing Arts and Sciences in Teaching & Learning Deep Impact Mission: Flyby camera capturing the image when impactor spacecraft collides with Tempel 1 on July 3rd. Dr. J.J. Voice: 019-455-1621 email: drjjlanita@hotmail.com; jjnita@salam.uitm.edu.my Website: http://www3.uitm.edu.my/staff/drjj/drjj1.html Copyright DRJJ, ASERG, FSG, UiTM, 2004

Copyright DRJJ, ASERG, FSG, UiTM, 2004 “Education is the kindling of a flame, not the filling of a vessel” - Socrates. “Learning is not a spectator sport. You do not learn much just sitting in classes listening to teachers, memorizing prepackaged assignments, and spitting out answers. You must talk about what you are learning, write reflectively about it, relate it to past experiences, and apply it to your daily lives. You must make what you learn part of yourselves.”   -Source:"Implementing the Seven Principles: Technology as Lever" by Arthur W. Chickering and Stephen C. Ehrmann 11/28/2018 Copyright DRJJ, ASERG, FSG, UiTM, 2004 Copyright DRJJ, ASERG, FSG, UiTM, 2004

Copyright DRJJ, ASERG, FSG, UiTM, 2004 Learning Objectives/Intended Learning Outcome: At the end of this session, participants should be able to: State, discuss and apply the terminologies used in thermodynamics to daily life. State and identify origins and transformations of the many different forms of energy State and discuss the characteristics and description of changes from and to a system State and discuss the zeroth law of thermo. 11/28/2018 Copyright DRJJ, ASERG, FSG, UiTM, 2004 Copyright DRJJ, ASERG, FSG, UiTM, 2004

Basic Concepts of Thermodynamics – The science of Energy CHAPTER 1 Basic Concepts of Thermodynamics – The science of Energy

FIGURE 1–5 Some application areas of thermodynamics. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. FIGURE 1–5 Some application areas of thermodynamics. 1-1

Steam Power Plant

FIGURE 1–13 System, surroundings, and boundary. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. FIGURE 1–13 System, surroundings, and boundary. 1-3

Copyright © The McGraw-Hill Companies, Inc Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. FIGURE 1–14 Mass cannot cross the boundaries of a closed system, but energy can. 1-4

Dynamic Energies cross in and out Systems Win Wout Dynamic Energies cross in and out NO VOLUME CHANGE Vinitial = Vfinal V = constant Qin Qout A rigid tank

NO dynamic energy transfer Systems NO mass transfer min = mout = 0 NO dynamic energy transfer Ein = Eout = 0 An isolated system

Copyright © The McGraw-Hill Companies, Inc Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. FIGURE 1–17 A control volume may involve fixed, moving, real, and imaginary boundaries. 1-5

Open system devices Throttle Heat Exchanger Copyright DRJJ, ASERG, FSG, UiTM, 2004

The system can be either open or closed. The concept of a property Properties Properties: Temperature Pressure Volume Internal energy Entropy System The system can be either open or closed. The concept of a property still applies.

First Law of Thermodynamics System expands Movable boundary position gone up System System A change has taken place.

NOT ADDITIVE OVER THE SYSTEM. Classes of properties Extensive MASS, m VOLUME, V ENERGY, E ADDITIVE OVER THE SYSTEM. Intensive TEMPERATURE, T PRESSURE, P DENSITY Specific properties NOT ADDITIVE OVER THE SYSTEM.

Box with 3 sections after equilibrium Intensive: not size independent Classes of properties Box with 3 sections after equilibrium Intensive: not size independent  = 1 = 2 = 3 = V/m e = e1 = e2 = e3 = E/m T, P Extensive: Total : V = V1 + V2 + V3 E = E1 + E2 + E3 m = m1 + m2 + m3

State A set of properties describing the condition of a system States State A set of properties describing the condition of a system A change in any property, changes the state of that system

Equilibrium A state of balance States Equilibrium A state of balance Thermal – temperature same at all points of system Mechanical – pressure same at all points of system at all time Phase – mass of each phase about the same Chemical – chemical reaction stop

States State postulate Must have 2 independent intensive properties to specify a state: Pressure & specific internal energy Pressure & specific volume Temperature & specific enthalpy

Processes and cycles

First Law of Thermodynamics Properties will change indicating change of state System E1, P1, T1, V1 To E2, P2, T2, V2 Win Wout Mass in Mass out Qin Qout

FIGURE 1–25 A process between states 1 and 2 and the process path. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. FIGURE 1–25 A process between states 1 and 2 and the process path. 1-6

FIGURE 1–28 The P-V diagram of a compression process. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. FIGURE 1–28 The P-V diagram of a compression process. 1-7

Thermodynamic process State 1 State 2 p V T

Example: Heating water Heat supplied by electricity or combustion. T1 T1+dT T1+2dT T2 ….

Theater System analysis of the slow heating process: Energy in via electricity or gas combustion System Boundary Neglect vapor loss Twater Theater Assume no heat losses from sides and bottom.

Theater System analysis for the water under equilibrium processes: Heating via an equilibrium process Energy In Twater Theater Reversed process of slow cooling, which is reversible for the water Energy Out

Processes & Equilibrium States What is the state of the system along the process path? p V T S1 S2 Process Path

Thermodynamic process State 1 State 2 Process 1 p V Process 2

P1 P2 Process Path I Process Path II State 1 State 2 Thermodynamic cycles P1 P2 State 1 State 2 Process Path I Process Path II

Example: A steam power cycle. Turbine Mechanical Energy to Generator Heat Exchanger Cooling Water Pump Fuel Air Combustion Products System Boundary for Thermodynamic Analysis

Types of Energy

Dynamic System Changes occuring within system Types of Energy Dynamic Heat, Q Work, W Energy of moving mass, Emass Crosses in and out of system’s boundary System Internal, U Kinetic, KE Potential, PE Changes occuring within system

Internal, U Sensible, Relates to temperature change Latent Types of Energy Internal, U Sensible, Relates to temperature change Latent Relates to phase change

Copyright © The McGraw-Hill Companies, Inc Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. FIGURE 1–32 The various forms of microscopic energies that make up sensible energy. 1-8

Kinetic Changes with square of velocity Types of Energy Kinetic Changes with square of velocity KE = (mv2)/2, kJ; ke = v2/2, kJ/kg If velocity doubles, KE = (m(2v)2)/2 = (4mv2)/2, kJ If decrease by ½, then KE = (m(v/2)2)/2 = (mv2)/8, kJ

Potential Changes with vertical position, Types of Energy Potential Changes with vertical position, PE = mg(yf - yi) = mgh, kJ; pe = gh, kJ/kg If position above reference point doubles, PE = mg(2h), kJ; pe = g2h, kJ/kg If decrease by ½, then PE = mgh/2, kJ; pe = gh/2, kJ/kg

APPLICATION OF THE EQUILIBRIUM PRINCIPLE Zeroth Law of Thermodynamics Heat, and Temperature Copyright DRJJ, ASERG, FSG, UiTM, 2004

Temperature & heat...

Our sense of the direction of Heat & temperature Large body at constant temperature T1 T2<T1 Our sense of the direction of heat flow - from high to low temperature.

Temperature and heat are related. For metals, high heat flow - diathermal materials. T1 T2 For nonmetals, low heat flow - insulating.

Caloric definition of temperature Isolating boundaries

Bring systems into thermal contact and surround with an isolating -- adiabatic -- boundary. Initial configuration of the closed, combined systems with a diathermal wall between the two. T1 T2

Heat is observed to flow from the subsystem at the higher temperature to that with the lower temperature. T1 T2

The final observed state of the total system is that when the temperatures are equal. Heat flow from subsystem 1 to subsystem 2 decreases in time. T1,final T2,final

Zeroth Law of Thermodynamics...

Thermal equilibrium T1 T2 T1,final T2,final Initial State: Final State:

Demonstration of the Zeroth Law Two subsystems in equilibrium with a third subsystem Adiabatic Diathermal B D A C

The Zeroth Law Two systems in thermal equilibrium with a third system are in thermal equilibrium with each other.

FIGURE 1–41 The greenhouse effect on earth. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. FIGURE 1–41 The greenhouse effect on earth. 1-11

Copyright © The McGraw-Hill Companies, Inc Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. FIGURE 1–45 P versus T plots of the experimental data obtained from a constant-volume gas thermometer using four different gases at different (but low) pressures. 1-12

FIGURE 1–47 Comparison of temperature scales. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. FIGURE 1–47 Comparison of temperature scales. 1-13

FIGURE 1–51 Absolute, gage, and vacuum pressures. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. FIGURE 1–51 Absolute, gage, and vacuum pressures. 1-14

Copyright © The McGraw-Hill Companies, Inc Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. FIGURE 1–55 The pressure is the same at all points on a horizontal plane in a given fluid regardless of geometry, provided that the points are interconnected by the same fluid. 1-15

FIGURE 1–57 The basic manometer. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. FIGURE 1–57 The basic manometer. 1-16

FIGURE 1–61 Schematic for Example 1–8. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. FIGURE 1–61 Schematic for Example 1–8. 1-17

FIGURE 1–63 The basic barometer. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. FIGURE 1–63 The basic barometer. 1-18

Copyright © The McGraw-Hill Companies, Inc Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. FIGURE 1–75 Some arrangements that supply a room the same amount of energy as a 300-W electric resistance heater. 1-19

Copyright © The McGraw-Hill Companies, Inc Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. FIGURE 1–39 Ground-level ozone, which is the primary component of smog, forms when HC and NOx react in the presence of sunlight in hot calm days. 1-9

Copyright © The McGraw-Hill Companies, Inc Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. FIGURE 1–40 Sulfuric acid and nitric acid are formed when sulfur oxides and nitric oxides react with water vapor and other chemicals high in the atmosphere in the presence of sunlight. 1-10

FIGURE 1–7 The definition of the force units. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. FIGURE 1–7 The definition of the force units. 1-2