열과 역학에너지와의 관계를 바탕으로 열현상을 연구하는 분야를 열역학이라고 부른다(여기서 열역학 [Thermodynamics] 이란 뜻은 희랍어에서 열의 운동학이란 뜻이다). 열역학은 물질 내의 원자나 분자의 존재를 알기 전인 19세기 초에 발전된 분야이다. 열역학은 계를 구성하는 원자나 분자의 운동현상에 관한 미시적 지식이 없이도 계의 거시적 물리량의 변화를 알 수 있는 과학적 방법론을 제공한다. 열역학의 기초는 에너지 보존법칙과 열의 이동 방향에 관한 법칙이다. 이들 두 법칙으로 증기기관, 핵융합로 등의 열기관 또는 냉난방장치에 관한 기초이론을 확립할 수 있다.

Chapter 1 열역학의 기초

1.1 온도와 열 그리고 열 현상 ·························································· 8

(1) 온도(temperature) ········································································· 10

(2) 열(heat, thermo), 열에너지(thermal energy) ····························· 12

(3) 열의 이동 ····················································································· 14

(4) 열량(heat quantity)과 열용량(heat capacity) ···························· 16

(5) 열역학 제 0 법칙 ········································································· 18

1.2 일(work)과 열(heat) 그리고 열역학 ····································· 20

(1) 일(work) ························································································ 22

(2) 일의 표기 ····················································································· 24

(3) 일의 열당량, 열의 일당량 ························································ 28

(4) 에너지(energy, erg) ····································································· 30

(5) 외부에너지(external energy) ······················································· 32

(6) 내부에너지(internal energy) ······················································· 34

(7) 에너지방정식(equation of energy) ············································ 36

1.3 열역학의 용어와 정의 ································································ 38

(1) 열역학적 계(system) ··································································· 40

(2) 상태(state) 및 상태량(property) ················································· 42

(3) 상평형(phase equilibrium)과 상태량의 종류 ··························· 44

(4) 열역학적 평형상태(thermodynamic equilibrium state) ··········· 46

(5) 과정(process)과 사이클(cycle) ··················································· 48

(6) 가역(reversible)과정과 비가역(irreversible)과정 ······················ 50

(7) 준평형 / 정적 과정(quasi-equilibrium / statical process) ··········· 52

(8) 열역학(thermodynamics)과 미분(differential) ··························· 54

(9) 압력(pressure) ··············································································· 60

(10) 비체적, 비중량 및 밀도 ···························································· 62

(11) 비열(specific heat) / 정적비열, 정압비열 ······························· 64

(12) 단위(unit) 및 단위계(unit system) ·········································· 66

(13) 일(work), 열(heat) 및 동력(power)의 단위 ··························· 70

연습문제 ······························································································ 73

Chapter 2 열역학 제 1 법칙

2.1 열역학 제 1 법칙의 의미 ··························································· 86

2.2 열역학 제 1 법칙과 에너지보존의 법칙 ································· 88

(1) 열역학 제 1 법칙 ········································································· 88

(2) 제 1 종 영구기관 ········································································· 90

(3) 에너지보존의 법칙 ····································································· 92

2.3 밀폐계에 대한 열역학 제 1 법칙 ············································· 94

(1) 열역학 제 1 법칙의 기본식 ······················································· 94

(2) 에너지 관련 변형식 ··································································· 96

(3) 에너지 방정식 / 열역학 제 1 법칙의 제 1 공식 ···················· 98

(4) 밀폐계에 대한 열역학 제 1 법칙의 고찰 ····························· 100

2.4 개방계에 대한 열역학 제 1 법칙 ··········································· 102

(1) 유동일과 엔탈피 ······································································· 104

(2) 총 에너지량 ··············································································· 106

(3) 에너지 입·출량 ·········································································· 108

(4) (일반) 에너지보존의 식 ·························································· 110

(5) 정상유동 과정(steady flow process) ······································· 112

(6) (정상유동 과정의) 에너지 유입·유출 ··································· 114

(7) 에너지방정식 / 열역학 제 1 법칙의 제 2 공식 ···················· 116

(8) 개방계에 대한 열역학 제 1 법칙의 고찰 ··························· 118

2.5 엔탈피(enthalpy) ······································································· 120

(1) 엔탈피와 내부에너지 ······························································· 120

(2) 엔탈피의 열역학적 특성함수 ················································· 122

(3) 엔탈피, 열화학 방정식 ···························································· 124

(4) 엔탈피의 공학적 활용 ····························································· 126

2.6 열역학 제 1 법칙(에너지보존의 법칙)의 응용 ···················· 128

(1) 정상유동 과정의 일 ·································································· 128

(2) 정상유동 과정의 일 해석 ························································ 130

2.7 절대일과 공업일 ········································································ 132

(1) 절대일 ·························································································· 132

(2) 밀폐계에서의 절대일 ································································ 134

(3) 공업일 ·························································································· 136

(4) 개방계에서의 공업일 ································································ 138

2.8 열역학 제 1 법칙에 의한 일 ․ 에너지 해석 ··························· 140

연습문제 ·································································································· 143

Chapter 3 이상기체(완전가스)

3.1 완전가스(perfect gas) ····························································· 156

3.2 완전가스의 특성식(equation of state) ································ 158

(1) Boyle의 법칙 ·············································································· 158

(2) Charles의 법칙 ············································································ 160

(3) 이상기체의 상태방정식(완전가스의 특성식) ····················· 162

3.3 기체상수(gas constant, 가스정수) ······································· 164

(1) 일반 가스정수 ············································································ 164

3.4 완전가스의 내부에너지 ···························································· 170

(1) Joule의 법칙 ··············································································· 170

(2) Joule-Thomson의 효과 ······························································· 172

3.5 완전가스의 상태변화( I ) / 비열 ············································· 174

(1) 정적비열 ······················································································ 174

(2) 정압비열 ······················································································ 176

(3) 비열 差/ 정압비열 과 정적비열 의 관계 ···················· 178

(4) 비열 比/ 정압비열 과 정적비열 의 관계 ···················· 180

3.6 완전가스의 상태변화( II ) / 가역변화 ···································· 182

(1) 정적변화(constant volume change) ··········································· 186

(2) 정압변화(constant pressure change) ········································ 188

(3) 등온변화(constant temperature change) ··································· 190

(4) 단열변화(adiabatic change) ······················································· 192

(5) 폴리트로픽 변화(polytropic change) ······································· 198

3.7 완전가스의 상태변화(Ⅲ) / 비(非)가역 변화 ························ 210

3.8 혼합가스(mixed gas) ································································ 212

(1) Dalton의 법칙 ············································································ 214

(2) 혼합가스의 가스정수 ······························································· 216

(3) 혼합가스의 분자량 ··································································· 218

(4) 온도와 압력이 다른 가스의 혼합 / 일정체적 하의 밀폐계에서의 혼합 ········································ 220

연습문제 ································································································· 223

Chapter 4 열역학 제 2 법칙

4.1 열의 흐름(flow of heat) ························································ 236

4.2 가역과정(reversible process) / 준 정적과정(quasi-static process) ···································· 238

4.3 비가역 과정(irreversible process) ········································· 240

4.4 열역학 제 2 법칙의 여러 가지 표현 ····································· 242

(1) 에너지의 가치변화와 방향성 ················································· 242

(2) Clausius의 서술 ········································································· 244

(3) Kelvin(Thomson)-Planck의 서술 ·············································· 246

4.5 제 2 종 영구기관 / Ostwald의 서술 ······································· 248

4.6 열역학 제 2 법칙의 물리적 의미 ··········································· 250

4.7 일반 사이클 ················································································ 252

(1) 유효일(effective work) / 유용일 ··············································· 254

(2) 열효율과 성적계수 ··································································· 256

4.8 카르노사이클(Carnot cycle) ··················································· 258

(1) 카르노사이클의 4 과정 ···························································· 260

(2) 카르노사이클의 열효율  ···················································· 262

(3) 카르노사이클 열효율의 증명 ·················································· 264

(4) 카르노의 정리-I ········································································· 266

(5) 카르노의 정리-II ········································································ 268

(6) 카르노의 정리-III ······································································· 270

4.9 열역학적 온도(thermodynamic temperature) ··················· 272

(1) 열역학적 온도눈금(thermodynamic temperature) ··················· 272

(2) 카르노 함수(Carnot function) ··················································· 274

(3) 열역학적 온도의 성질 ······························································ 276

(4) Kelvin의 절대온도 ····································································· 278

(5) Q / T ····························································································· 280

4.10 가역사이클과 Clausius 폐적분 ············································· 282

4.11 Clausius의 부등식(inequality of clausius) ······················ 284

4.12 엔트로피(entropy) ·································································· 286

4.13 엔트로피(entropy) 증가의 법칙 ·········································· 288

(1) 비가역변화의 엔트로피-I ························································· 288

(2) 비가역변화의 엔트로피-II ························································ 290

4.14 엔트로피(entropy)의 계산 ···················································· 294

(1) 고체 및 액체 ············································································ 296

(2) 기체(이상기체) ········································································· 296

4.15 완전가스 엔트로피의 일반적인 변화 ·································· 298

(1)    의 항으로 표시 ······························································· 298

(2)   의 항으로 표시 ································································· 298

(3)    의 항으로 표시 ································································· 300

4.16 가역변화의 엔트로피 계산 ···················································· 302

(1) 정적(등적)변화 ··········································································· 302

(2) 정압(등압)변화 ··········································································· 302

(3) 등온(정온)변화 ··········································································· 302

(4) 단열변화 ······················································································ 302

(5) 폴리트로픽변화 ·········································································· 304

4.17 (이상기체의) 비가역변화의 엔트로피 계산 ······················ 306

(1) 마찰이 있는 경우 ······································································ 306

(2) 온도차가 있는 두 물체 사이의 열 이동 ···························· 306

(3) 교축 ····························································································· 306

4.18 (혼합기체의) 비가역변화의 엔트로피 계산 ······················· 308

(1) 확산 ··························································································· 308

(2) 혼합 ····························································································· 310

4.19 엔트로피 선도(entropy diagram) ·········································· 314

(1) 열선도 ························································································· 314

(2) 등압변화 ····················································································· 316

(3) 등적변화 ····················································································· 318

(4) 카르노사이클 ············································································· 320

4.20 엔트로피와 열역학 제 3 법칙 ················································· 322

(1) 에너지의 질(質)적 변화 ·························································· 322

(2) 열역학 제 3 법칙 ······································································· 324

연습문제 ··································································································· 327

Chapter 5 에너지의 유용성

5.1 에너지의 유용성 / 유용에너지 ················································· 342

5.2 유용에너지와 무용에너지 ························································· 344

5.3 엔트로피의 생성 ········································································· 346

(1) 마찰이 일어나는 경우 ····························································· 346

(2) 비가역 단열과정 ······································································· 346

5.4 에너지의 유용(효)성의 척도 ····················································· 348

(1) 무용에너지의 증가 ··································································· 348

(2) 엔트로피 변화량 ······································································· 350

5.5 가역일, 유용일, 비(非)가역성 ·················································· 352

5.6 유용일 손실 ················································································· 354

5.7 유용에너지의 소산(dissipation of energy) ···························· 356

5.8 에너지의 잠재일(potential work) / 엑서지(exergy) ············· 358

5.9 (유용)에너지의 일 ······································································· 360

5.10 유용일(available work)과 실제일(net work) ······················ 362

5.11 최대 유용일 / 엑서지(exergy) ············································· 364

5.12 개방계의 엑서지 ······································································ 366

5.13 엑서지 / 엑세르기 ····································································· 368

5.14 역학적에너지의 엑서지 ·························································· 370

(1) 운동에너지의 엑서지 ··························································· 370

(2) 위치에너지의 엑서지 ··························································· 370

5.15 내부에너지 ․ 엔탈피의 엑서지 ··············································· 372

5.16 엑서지 손실 / 제 1 종 손실 / anergy ································ 374

5.17 엑서지 소멸 / 제 2 종 손실 / 비(非)가역 손실 ···················· 376

5.18 엑서지의 실용계산법 ······························································ 378

(1) 비열을 알 때의 물질의 엑서지 ··········································· 378

(2) 압력을 알 때의 물질의 엑서지 ··········································· 379

(3) 외계와 다른 분율을 갖는 혼합기체의 엑서지 ················· 379

5.19 Helmholtz 함수 / 자유에너지 ················································· 380

5.20 Gibbs / 자유엔탈피 ·································································· 382

5.21 에너지변환의 분류와 효율 ···················································· 384

(1) 엔트로피 효율  ···································································· 384

(2) 열효율(제 1 법칙 효율)  ···················································· 386

(3) 엑서지효율(제 2 법칙 효율) Ⅱ ············································ 388

5.22 에너지의 질(質)적 평가 ························································ 390

5.23 바람직한 에너지 이용 방식 ·················································· 392

5.24 바람직한 에너지 변환 방식 ·················································· 394

연습문제 ·································································································· 399

Chapter 6 열에너지의 변환

6.1 공기표준 사이클 ········································································ 418

6.2 (공기표준) 카르노사이클 ························································ 420

(1) 카르노사이클의 구성 ··························································· 422

(2) 카르노사이클의 열효율 ······················································· 424

(3) 카르노사이클의 공학적 가치 ················································· 426

6.3 (공기표준) 피스톤형 열기관 사이클 ···································· 428

(1) 지시계(indicator) ········································································ 430

6.4 (공기표준) Otto 사이클 ···························································· 432

(1) 정적사이클의 해석 ··································································· 434

(2) Otto 사이클의 열효율 ······························································· 436

6.5 (공기표준) Diesel 사이클 ························································· 438

(1) 정압사이클의 해석 ··································································· 440

(2) Diesel 사이클의 열효율 ···························································· 442

6.6 (공기표준) 혼합사이클 ····························································· 444

(1) 혼합사이클의 구성 ··································································· 446

(2) 혼합사이클의 열효율 ······························································· 448

6.7 각(공기표준) 피스톤형 열기관 사이클의 비교 ··················· 450

(1) Carnot 사이클과 Otto 사이클의 비교 ····································· 450

(2) Otto 사이클과 Diesel 사이클의 비교 ······································ 452

6.8 (공기표준) 회전형 열기관 사이클 ········································· 456

(1) 브레이턴사이클의 열효율 ······················································· 458

(2) 브레이턴사이클의 출력 ··························································· 460

(3) 브레이턴사이클의 최대일 ······················································· 462

6.9 브레이턴 재생사이클 ································································ 464

(1) 브레이턴 재생사이클의 열효율 ··········································· 466

(2) 브레이턴 재생사이클의 해석과 적용(제트기관) ·············· 468

6.10 기타 사이클 ············································································· 470

(1) Ericsson 사이클 ········································································· 470

(2) Stirling 사이클 ··········································································· 470

연습문제 ································································································ 473