thermodynamics - s3.amazonaws.com · • thermodynamics is a scientific subject routinely utilized...

THERMODYNAMICS

DEFINED

And

DISCUSSED

Thomas E. Eaton, CFI, PE, ScD

EATON ENGINEERING CO.

Harrodsburg, Kentucky

• Thermodynamics Defined and Discussed, Copyright 2016, Eaton Engineering Co.

THERMODYNAMICS

WHAT ? ? ?

IS ? ? ?

THERMODYNAMICS

? ? ? ? ? ? ? ? ? ? ? ? • Thermodynamics Defined and Discussed, Copyright 2016, Eaton Engineering Co.

WHAT

IS

THERMODYNAMICS

DUUUUHHHHHH

STRANGE

MYSTICAL

REMOTE

WEIRD

FUZZY

???????????

GOLLY GEE

WHY IS THERMODYNAMICS OF INTEREST

IN FIRE INVESTIGATION ? ? ?

NFPA

921 [ A GUIDE ]

NFPA

1033 [ A STANDARD ]


THE TECHNICAL “TOPICS” OF NFPA 1033: 2014 - Professional Qualifications for Fire Investigator

FIRE SCIENCE

FIRE CHEMISTRY

FIRE INVESTIGATON

FIRE ANALYSIS

FIRE INVESTIGATION METHODOLOGY

FIRE INVESTIGATION TECHNOLOGY

HAZARDOUS MATERIALS

ELECTRICITY AND ELECTRICAL SYSTEMS

THERMODYANMICS

THERMOMETRY

FIRE DYNAMICS

EXPLOSION DYNAMICS

COMPUTER FIRE MODELING

FIRE PROTECTION SYSTEMS

FAILURE ANALYSIS AND ANALYTICAL TOOLS

EVIDENCE DOCUMENTATION, COLLECTION AND PRESERVATION


NFPA 921 – 2014: “Guide for Fire and Explosion Investigations”

NFPA 1033 – 2014: “Standard for Professional Qualifications of Fire Investigator”

•NFPA 1033 – 2014: THERMODYNAMICS: NOT DEFINED

•NFPA 921 – 2014: THERMODYNAMICS: NOT DEFINED

The Dictionary of Thermodynamics

The Dictionary of Thermodynamics

Dr. A.M. James, 1976, 262 pp. John Wiley & Sons

“Thermodynamics” - NOT DEFINED

THE DICTIONARY (2009) SPECIFIED BY

NFPA 921 AND NFPA 1033

WEBSTER’S COLLEGIATE DICTIONARY

“THERMODYNAMICS” Defined

MERRIAM-WEBSTER’S COLLEGIATE DICTIONARY Eleventh Edition, 2009, p. 1297

• “thermodynamics \ (1854)

• 1: physics that deals with the mechanical action or relations to heat.

• 2: thermodynamic processes and phenomenon…. “

THERMODYNAMICS - - - Once Defined, It’s NOT SO STRANGE

• THERMODYNAMICS IS DIRECTLY RELATED TO FIRE INVESTIGATION.

• THERMODYNAMICS APPLIES TO ANY PROCESS WHERE ENERGY CONVERSION IS INVOLVED.

• GENERALLY, ENERGY CONVERSION IS INVOLVED WHERE THERE IS CHANGE.

• WHEN SOMETHING HAPPENS, THERMODYNAMICS IS INVOLVED.

• CONSEQUENTLY, FIRE INVESTIGATORS ARE FAMILIAR WITH

“THERMODYNAMICS"

Thermodynamics Defined, Copyright 2016. Eaton Engineering Co.

THERMODYNAMICS - - - It’s NOT SO STRANGE

• IGNITION INITIATES COMBUSTION IS A THERMODYNAMICS PROCESS

– Open Flames, Pilot Flames, Electrical Sparks (Transient Discharges), – Electrical Arcs (Sustained Discharges), Electric Resistance Heating, Chemical Reactions, – Friction, etc.

• COMBUSTION IS A PROCESS THAT CONVERTS CHEMICAL ENERGY IN FUELS TO THERMAL ENERGY, i.e., A THERMODYNAMIC PROCESS…

• THERMODYNAMICS IS A SCIENTIFIC SUBJECT ROUTINELY UTILIZED IN FIRE INVESTIGATION

• FIRE INVESTIGATORS ARE ALREADY FAMILIAR WITH “THERMODYNAMICS”

• Note Also: FIRE INVESTIGATORS ARE FAMILIAR WITH “FIRE DYNAMICS”. THIS IS BECAUSE ORIGIN DETERMINATION IS THE RECONSTRUCTION OF THE DYNAMIC DEVELOPMENT OF A FIRE FROM EXTINGUISHMENT (As Found) BACK TO IGNITION (First Fuel Ignited)

THERMODYNAMICS

THE SCIENCE

OF

ENERGY CONVERSION

THERMODYNAMICS

THE BRANCH OF THERMAL

SCIENCE CONCERNING

THE

CONVERSION OF ENERGY

FROM ONE FORM TO ANOTHER

THERMODYNAMICS

DEFINED AND DISCUSSED

WITHOUT

EQUATIONS, MATHEMATICS, COMPUTIONS,

AND OTHER CONFUSING ASPECTS

THERMODYNAMICS

THE STUDY OF

THE PRINCIPLE OF ENERGY CONSERVATION,

THE INHERNET RESTRICTIONS REGARDING ENERGY

CONVERSION,

THE TEMPERATURE OF SUBSTANCES, AND

THE THERMAL-PHYSICAL PROPERTIES OF

SUBSTANCES

Thermodynamics Defined and Discussed, Copyright 2016, Eaton Engineering Co.

Definition Methodology

Find and Quote

“ Thermodynamics is … ” in Engineering, Scientific, and Technical

Literature (Textbooks, Treatises, Technical Papers, Handbooks, Encyclopedias, Journals,

Publications, etc.)

Discussion Methodology

Describe What

“ Thermodynamics is … ”

And the “Laws of Thermodynamics”

Without Equations, Mathematics

WHAT IS

THERMODYNAMICS

? ? ? ? ? ? ?

The DEFINITION is --- Surprisingly Elusive,

Sometimes Confused,

Sometimes Inaccurate,

Often Not Mentioned

“Thermodynamics is . . .”

THERMODYNAMICS

SOME TEXTBOOK DEFINITIONS

• “Thermodynamics is the science of the relationship

between heat, work, and the properties of systems,”

– Keenan, Thermodynamics, 1941

• “One very excellent definition of thermodynamics is

that it is the science of energy and entropy….”

– Van Wylen and Soontag, Fundamentals of Classical

Thermodynamics, 1965

THERMODYNAMICS

SOME SCIENTIST’S DEFINITIONS

• “The subject matter of thermodynamics is based

essentially on two fundamental postulates (or laws)

which summarize actual experience with regard to the

interconversion of different forms of energy. These

are called the first and second laws of

Thermodynamics,”

• Samuel Glasstone, Thermodynamics for Chemists,

1947

THERMODYNAMICS


“THERMODYNAMICS is mainly concerned with the

transformations of heat into mechanical work and the

opposite transformations of mechanical work into heat.

Only in comparatively recent times have physicists

recognized that heat is a form of energy that can be

changed into other forms of energy.”

– Enrico Fermi, Thermodynamics, 1936

THERMODYNAMICS


“Thermodynamics is the science of the relationship

between heat, work, and other forms of energy in

combination with the physical properties of the

substances involved.”

- Clark S. Robinson, Thermodynamics of Firearms,

1943.

THERMODYNAMICS


“… As it has become apparent that thermodynamics

goes much deeper than the consideration of steam

engines associated with its historical beginnings, it

has also become apparent that biology is at its roots

is a profoundly thermodynamic subject.”

Harold J. Morowitz, Entropy for Biologists, 1970

FIELDS OF THERMODYNAMIC STUDY

• THERMAL PHYSICS

• METALLURGY

• BIOLOGY

• GEOLOGY

• MECHANICAL ENGINEERING

• ENERGY SYSTEMS

• CHEMISTRY • MATERIALS • MOLECULES • HYDROCARBONS • CHEMICAL ENGINEERING • ELECTRICAL ENGINEERING • FIRE PROTECTION ENGINEERING • NATURAL SYSTEMS • ASTRONOMY • BIOMECHANICS • ELECTRICITY • MAGNETISM • FIRE SCIENCE

THERMODYNAMICS

ENGINEERING DEFINITION

“ THERMODYNAMICS is

the study of energy,

its transformations, and

its relation to the states of matter.”

--- “Thermodynamics and Refrigeration Cycles,”

Chapter 2, 2013 ASHRAE HANDBOOK: FUNDAMENTALS

(ASHRAE, 2013), p. 2.1

APPLICATIONS OF THERMODYNAMICS OF INTEREST TO FIRE INVESTIGATORS

• COMBUSTION

• IGNITION

• PYROLYSIS

• PHASE CHANGE

• HYDRAULICS

• INSTRUMENTATION

• PHOTOGRAPHY

• WATER PUMPS

• GASOLINE / DIESEL ENGINES

• ELECTRICITY GENERATION

• TELECOMMUNICATIONS

• ELECTRONICS

THERMODYNAMICS

SOME ENCYCLOPEDIA DEFINITIONS

• “Thermodynamics is the science

of the Transformation of Energy.”

• McGraw-Hill Concise Encyclopedia of Physics, 2005

THERME --- DYNAMIS

(HEAT) --- (POWER)

In Lord Kelvin’s Words …

• “… Hence, Thermo-dynamics falls naturally into two Divisions, of which the subjects are respectively,

the relation of heat to the forces acting between contiguous parts of bodies, and the relation of heat to electrical energy ….” *

* Thompson, William (Lord Kelvin), “Fundamental Principles of General Thermo- Dynamics Recapulated,” Transactions of the Royal Society of Edinburg, Vol. XX1,Part I, 1856, pp. 123 – 171.

THERMODYNAMICS WHERE DOES IT COME FROM ? ? ?

BASED ON

EXPERIMENTAL OBSERVATION USING THE

SCIENTIFIC METHOD

What is SCIENCE ? ? ?

From the Latin: “scientia” ……

“KNOWLEDGE” “SCIENCE: knowledge about or study of the natural world based on facts learned through experiments and observation….” * * www.meriam-webster.com/dictionary/science

Benjamin Thompson, Count Rumford

HEATING CAUSED BY BORING CANNON (A RISE IN COOLING WATER TEMPERATURE)

“Heat is a Form of Motion…”

Philosophical Transactions, V88, 1798

THE RUMFORD FIREPLACE

http://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0ahUKEwjl5M7d_pXLAhUJRCYKHT97BCYQjRwIBw&url=http://www.rumford.com/training/design.html&psig=AFQjCNG0ltj4cE1n88rJ90G58hGizS_H_Q&ust=1456595297074263

HEAT TO WORK THE OBSESSION OF EARLY

THERMODYNAMICS -------- Common Examples -------

GASOLINE ENGINES

DIESEL ENGINES

STEAM ENGINES

STEAM TURBINES

GAS TURBINES

FIREARMS

ARTILLERY

EXPLOSIVES

ROCKETS

BOMBS

THERMODYNAMIC PROCESSES OF INTEREST TO FIRE INVESTIGATORS

• Combustion / Fire --------- Chemical to Thermal

• Explosion --------------------- Chemical to Thermal/Mechanical

• Pyrolysis ---------------------- Thermal to Chemical

• Ignition Source ------------- Flames, Sparks, Arcs, Resistance Heating, etc.

• Radiation --------------------- Thermal to Electromagnetic

• Pumping ---------------------- Mechanical to Kinetic (Fluid Flow)

• Braking ------------------------ Kinetic to Mechanical

• Power Generation --------- Mechanical to Electric

• Communication ------------- Electrical to Electromagnetic

• Corrosion --------------------- Chemical to Chemical

• Control ------------------------ Electrical to Electrical

• Phase Change ------ Thermal to Physical State

• Arcs & Sparks ------- Electrical to Thermal

• Illumination --------- Electrical to Electromagnetic

THERMODYNAMICS Some Historical Observations

• The Conversion of Heat Produced by burning wood or coal in a boiler into mechanical work using a steam engine was of much interest.

• Into the early nineteenth century, “heat” was thought to be a substance called “Caloric.”

• Thermodynamics was primarily concerned with “Heat and Work” for well over a century. In many fields, it still is today.

• In the early Twentieth Century, Statistical thermodynamics develops

• In the mid-Twentieth Century, Non-Linear Thermodynamics is proposed.

• In the mid-Twentieth Century, thermodynamics expands into numerous scientific fields beyond “heat and power” of interest to engineers

• Classical Thermodynamics accomplishes great advances based on systems in equilibrium --- which restricts thermodynamic analysis to only energy conversion and deliberately ignores energy transport --- in order to simplify the analysis.

• Today, non-equilibrium thermodynamics addresses complex energy conversion and energy transport processes simultaneously: Thermodynamics and Heat Transfer Combined

LAWS OF THERMODYNAMICS

• ZEROTH --- TEMPERATURE (of Energy)

• FIRST --- CONSERVATION OF ENERGY

• SECOND --- LIMITATIONS ON ENERGY CONVERSION

TEMPERATURE

IS

A QUANTITATIVE MEASURE

OF ENERGY INTENSITY

TEMPERATURE

The “Zeroth” Law of

Thermodynamics

ENERGY INTENSITY

CREATED BY THE

KINETIC MOTION OF MATTER:

ATOMS, MOLECULES, PARTICLES

TEMPERATURE

ENERGY INTENSITY

CREATED BY THE KINETIC MOTION

OF MATTER OR PARTICLES

ROOM TEMPERATURE: 70-F

70 degrees F =

21 degrees C, Celsius

294 degrees K, Kelvin

530 degrees R, Rankine

0.025 eV, electron-Volts

TEMPERATURE

1 eV, electron Volt

=

11,604.5 degrees Kelvin

20,428 degrees Fahrenheit

ABSOLUTE ZERO

=

- 459.67 F ---- Fahrenheit

- 273.15 C --- Celsius

0.0 K ----------- Kelvin

0.0 R ----------- Rankine

0.0 eV -------- electron-Volts

TEMPERATURE

The Electron Volt - eV

1 electron Volt, 1 eV

=

11,604 Kelvin, degrees K

11,331 Celsius, degrees C

20,888 Rankine, degrees R

20,428 Fahrenheit, degrees F

TEMPERATURE

CONSTANT TEMPERATURE

INDICATES

EQUILIBRIUM

CONDITIONS

( UNIFORM THROUGHOUT )

WHAT

IS

ENERGY ! ! !

--- ENERGY ---

THE ABILITY TO CAUSE

CHANGE

ENERGY IN GENERAL

•KINETIC (Motion)

•POTENTIAL (Stored)

TYPES OF ENERGY

• THERMAL

• CHEMICAL

• MECHANICAL

• GRAVITATIONAL

• KINETIC

• VIBRATIONAL*

• ROTATIONAL*

• ELECTRICAL

• MAGNETIC

• ELECTROMAGNETIC

• NUCLEAR

• MASS

TEMPERATURE

IS

ENERGY ! ! !

--- THERMAL ENERGY ---

KINETIC ENERGY OF ATOMS,

MOLECULES, PARTICLES

TEMPERATURE

IS

ENERGY ! ! !

KE = ½ mV² = 3/2 kT

KE - mean particle energy

T -- temperature equates to E -- energy

TEMPERATURE

IS

ENERGY ! ! !

---THERMAL ENERGY---

TEMPERATURE = INTENSITY

HEAT = QUANTITY

PRESSURE

IS ALSO

ENERGY

---Example: Pneumatic Tire ---

PRESSURE = ENERGY INTENSITY

VOLUME OF AIR = ENERGY QUANTITY

PRESSURIZED

ELECTRICITY

IS

ENERGY

---ELECTRICAL ENERGY---

VOLTAGE = INTENSITY

CHARGE = QUANTITY

THERMODYNAMIC METHODS

CLASSICAL

STATISTICAL

NON-EQUILIBRIUM

THERMODYNAMIC ANALYSIS - - - BEGIN WITH SYSTEM SELECTION

SYSTEM

BOUNDARY

THERMODYANMIC SYSTEM SURROUNDINGS

THERMODYNAMIC SYSTEMS

• A THERMODYNAMIC SYSTEM IS AN OBJECT SELECTED TO APPLY THE LAWS OF

THERMODYNAMICS • - The Subject of Thermodynamic Investigation • Examples: room, molecule, atom, battery, boiler, lamp, planet, nozzle,

planet, engine, heater, etc.

• CLASSICAL THERMODYNAMICS DEFINES THE STATE (PHYSICAL) CONDITIONS THROUGHOUT THE THERMODYNAMIC SYSTEM TO BE IN EQUILIBRIUM, I.E., UNIFORM AT ANY GIVEN TIME

• Transfer processes driven by non-equilibrium conditions are not considered

THERMODYNAMIC SYSTEMS

• THE FUNDAMENTAL BASIS OF THERMODYNAMIC ANALYSIS --- SYSTEM SELECTION

• THE THERMODYNAMIC SYSTEM IS SELECTED FOR THE TASK AT HAND

• SELECT THE SYSTEM WISELY --- THE THERMODYANMICS SYSTEM IS USER SELECTED

• THE THERMODYNAMIC SYSTEM IS TYPICALLY THE OBJECT, REGION, ITEM, ETC.

BEING STUDIED

• e.g.: A Match, A Room, An Engine, A Cigarette, A Couch, – A Container, A Heater, A Switch, An Arc, A Chimney, A Lamp, – A Cardboard Box, Roll of Hay, A Trash Can, Cook Top, Oven, etc.

Thermodynamics Defined and Discussed, Copyright © 2016, Eaton Engineering Co.

THERMODYNAMIC ANALYSIS

• DEFINE THE CLASSICAL THERMODYNAMIC SYSTEM

• APPLY THE LAWS OF THERMODYNAMICS

• EXAMINE THE “CONDITIONS OF STATE” AT DIFFERENT CONDITIONS

• REQUIRE MATERIALS, SUBSTANCES, e.g., CONTENTS, OF THE THERMODYNAMIC

SYSTEM BE IN EQUILBRIUM - - - UNIFORM THROUGHOUT THE SYSTEM

• ANALYZE THE ENERGY CONVERTED FROM ONE FORM TO ANOTHER

• EVALUATE THE ‘LOST’ ENERGY, IRREVERSIBILITIES, ETC.


THERMODYNAMIC ANALYSIS

• THERMODYNAMIC STATE CONDITION - – The Physical Properties of the System Contents at a Given Point

• LIKE A PHOTOGRAPH ! ! ! -------

– DOCUMENTING SPECIFIC CONDITIONS – A SEQUENCE OF PHOTOGRAPHS IS LIKE A SERIES

• OF THERMODYNAMIC STATES

• THERMAL-PHYSICAL PROPERTY CHANGES BETWEEN THERMODYNAMIC STATES DETERMINE THE ENERGY CONVERSION


THERMODYNAMICS AND FIRE ORIGIN AND CAUSE ANALYSIS

• ORIGIN AND CAUSE INVESTIGATION

• LIKE TWO PHOTOGRAPHS ! ! ! -------

– DOCUMENTS SPECIFIC STATIC CONDITIONS – A SEQUENCE OF PHOTOGRAPHS IS LIKE A SERIES

• OF THERMODYNAMIC STATES IN EQUILIBRIUM

• THE FIRE ORIGIN AND CAUSE INVESTIGATION BEGINS WITH A “PHOTOGRAPH” OF THE FIRE SCENE, AS FOUND

• THE OBJECTIVE OF FIRE ORIGIN AND CAUSE ANALYSIS IS TO CREATE THE “PHOTOGRAPH” OF THE IGNITION OF THE FIRE

• THERMAL-PHYSICAL PROPERTY CHANGES BETWEEN THERMODYNAMIC STATE CONDITIONS (… “Photographs” DETERMINE THE ENERGY CONVERSION


THERMODYNAMIC SYSTEM MANDATES

• THE CONSERVATION LAWS APPLY –ENERGY –MASS –MOMENTUM


THERMODYNAMIC SYSTEM BOUNDARY REQUIREMENTS

“WHAT GOES INSIDE,

COMES OUT,

OR

EITHER STAYS INSIDE

THERMODYNAMICS METHODOLOGIES

CLASSICAL ----- e.g.: Engineering

STATISTICAL ---

MODERN --------- Non-Equilibrium

Equilibrium Thermodynamics Energy Transport Ignored System Analysis Simplified but Powerful Not Heat Transfer Macroscopic (Real World) System Static Analysis (Thermostatics) Emphasis on “Heat and Power”

Equilibrium Thermodynamics Microscopic (Atomic/Molecular) System Results Not Possible with Classical

Thermodynamics Not Heat Transfer

All Types of Energy Conversion Studied Non-equilibrium Thermodynamics Details of Energy Transport Considered HEAT TRANSFER INCLUDED Detailed Analysis inside Thermodynamic System in

Non-equilibrium or quasi-equilibrium conditions


EQUILIBRIUM Classical / Statistical - Engineering Method Commonly Utilized and Taught Energy Transport, Heat Transfer Ignored

NON-EQUILIBRIUM Modern - Much More complex A Developing Field Includes Computational Fire Dynamics


EQUILIBRIUM – Internal Conditions ALL THE SAME

Uniform Throughout

No Differences in Physical Properties (T,P,v, etc.)

No Mechanism for Energy Transport

NON-EQUILIBRIUM – PHYSICAL PROPERTIES VARY - P, T, v, V, E, C, etc.

NON-EQUILIBRIUM STATE CONDITIONS Exist

NON-Uniform Substance / Material Conditions within System

Differences (Variations), Gradients in Properties are Present

Driving Forces of Energy, Mass, and Momentum Transport

Energy Transport, Heat Transfer, etc. can be included

PRINCIPAL ELEMENTS OF

THERMODYNAMICS

• 1. Energy Conservation - The FIRST LAW

• 2. Energy Conversion - The SECOND LAW Limitations

• 3. Thermal Equilibrium – The ZEROTH LAW

• 4. Thermal-Physical Properties of Substances –

Thermodynamic Data

Concepts of Thermodynamics

• Temperature

• Energy

• Irreversibility

• Availability

• Entropy

• Time

• VIDEO 1. Steam

• VIDEO 2. Reversed Videos

Consequences of Thermodynamics, i.e.,

ENERGY CONVERSION

• ENERGY TRANSPORT

• IRREVERSIBILITY

• CHANGE

• TIME

SPECIFIC AREAS OF THERMODYNAMIC STUDY:

The Conversion of Energy from One Form to Another • COMBUSTION

• IGNITION

• PROPULSION

• EXPLOSIONS

• FIRE DYNAMICS

• COMPRESSIBLE FLOW

• GAS DYNAMICS

• TURBOMACHINERY

• ELECTRONICS

• ELECTRICITY

• BATTERIES

• CLIMATE

• METALS

• MINERALS

• SOLIDS

• POLYMERS

• CORROSION

OTHER AREAS OF THERMODYNAMIC STUDY

• ATMOSPHERES • OCEANS • PLANETS • BLACK HOLES

• IMAGING • INSTRUMENTATION • DETECTORS

• PIZZA • COOKIES • BAR-B-QUE • SUGAR AND STARCH • FAT

E N T R O P Y

WHAT IS ENTROPY

? ? ? ? ? A CONCEPT REGARDING THE SECOND LAW

“ 2 b : a process of degradation or running down …

or a trend to disorder ….”

(Merriam-Webster Collegiate Dictionary, 11th Ed.)

E N T R O P Y

WHAT IS ENTROPY ? ? ? IT IS A

THERMAL-PHYSICAL

PROPERTY OF MATTER Thermodynamics Defined and Discussed, Copyright 2016, Eaton Engineering Co.

E N T R O P Y

WHAT IS ENTROPY ? ? ?

A MEASURE OF

ENERGY AVAILABILITY Thermodynamics Defined and Discussed, Copyright 2016, Eaton Engineering Co.

E N T R O P Y

WHAT IS ENTROPY ? ? ? An Indication of the

“PREFERED DIRECTION

of a Given Process” *

* Parker, S.P., ed., McGraw-Hill Encyclopedia of Physics, 1993


E N T R O P Y

WHAT IS ENTROPY ? ? ? A MEASURE OF IRREVERSIBILITY ---

THE ENERGY UTILIZED OR CONSUMED IN THE ENERGY CONVERSION PROCESS

Referred to as “LOST” Work. Nevertheless, Energy cannot be ‘Lost’

--- THE ENERGY YOU USE TO CONVERT ENERGY

TO THE FORM YOU NEED ----


IRREVERSIBILITY

YOU HAVE TO

USE ENERGY TO

CONVERT ENERGY

E N T R O P Y

WHAT IS AVAILABILITY

The AMOUNT OF ENERGY

That Can Be CONVERTED

In a Thermodynamic System


AVAILABILITY

• FUELS HAVE CHEMICAL ENERGY AVAILABLE FOR CONVERSION INTO HEAT

• GIVEN AN IGNITION SEQUENCE

• COMBUSTION OR EXPLOSION OF THE FUEL RELEASES HEAT ENERGY

• Consider - Risk Assessment, • Hazard Classification, • Loss Prevention

IRREVERSIBILITY DECAY

CORROSION

DETERIORATION

CRUMBLING

LEAKAGE

BURNING

FLOWING

COOLING

MIXING

CONSUMPTION

TOPPLING

DISCHARGE

AGING

FALLING

DEFORMATION

DIFFUSION

CONDUCTION

DISPERSION

IRREVERSIBILITY

ENERGY MUST BE USED

TO TRANSPORT ENERGY

IN ORDER TO

CONVERT ENERGY FROM

ONE FORM TO ANOTHER

• VIDEO 3 - Fires, Explosions, Etc.

Irreversibility Video here

THERMODYNAMICS

The One Equation

THE FIRST LAW OF

THERMODYNAMICS:

A BALANCE SHEET of ENERGY

HEAT = ENERGY + WORK

dQ = dE + dW

THERMODYNAMICS

The One Equation

dQ = dE + dW

Change in Heat Energy =

Change in Internal Energy +

Work Done

“ d “ - - - ‘ means a change in ‘

THERMODYNAMICS

The One Equation . . .

Encompasses All Forms of Energy

dQ - A Change in Heat Energy

dW - Work Done by System

dE - A Change in ANY OTHER ENERGY- -

Electrical, Gravitational,

Chemical, Magnetic, Nuclear,

Electromagnetic, etc.

THERMODYNAMICS


Encompasses All Forms of Energy

dQ - Heat Energy

dW - Work

dE - ALL Other Forms of Energy - - -




THERMODYNAMICS


dE = ALL OTHER FORMS of Energy

dE = ALL OTHER FORMS OF ENERGY - - -




________________________

EXCEPT - - -

NOT = HEAT

NOT = WORK

Consequences of Thermodynamics

CHANGE

ENERGY - The Ability to Cause

CHANGE


ENERGY CONVERSION, I.E.,

THERMODYNAMICS,

CREATES CHANGE


TIME

IS PART OF CHANGE !!!


CHANGE

There always will be change !

DYNAMICS VS. STATICS ! ! !

IS IT

•THERMODYNAMICS OR IS IT REALLY

•THERMOSTATICS

? ? ? ? ? ? ? ? ? ? ?

THERMOSTATICS ! ! !

1. THERMODYNAMIC LAWS DO NOT INVOLVE RATES

2. ENERGY MUST BE TRANSFERRED TO CONVERT ENERGY BUT ENERGY DYNAMICS IS NOT A THERMODYNAMIC SUBJECT

3. THERMODYNAMICS DOES NOT ADDRESS THE RATE OR PATH OF A PROCESS

4. TIME IS NOT A THERMODYNAMIC VARIABLE


IS IT

FIRE DYNAMICS OR IS IT

FIRE STATICS ? ? ? ? ? ? ? ? ? ? ?


FIRE STATICS THE PHOTOGRAPHS

OF FIRE INVESTIGATION


FIRE DYNAMICS

THE VIDEO

OF FIRE INVESTIGATION

thermodynamics - s3.amazonaws.com · • thermodynamics is a scientific subject routinely utilized...

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