SHANDONG UNIVERSITY6-7 The Carnot Cycle（卡诺循环) Consider a closed system that consists ofa gas contained in an adiabaticpiston-cylinder device.The fourreversible processes are:(1)+(2)Process1-2:isothermalexpansion(等温膨胀）Energyon=Process2-3:adiabaticexpansion(绝热膨胀）sourceatTHProcess3-4:isothermalcompression（等温压缩）EProcess4-1:adiabaticcompression(绝热压缩）QH(a)Process 1-2
SHANDONG UNIVERSITY 6-7 The Carnot Cycle (卡诺循环) • Consider a closed system that consists of a gas contained in an adiabatic pistoncylinder device. • The four reversible processes are: 11 Process 1-2: isothermal expansion(等温膨胀) Process 2-3: adiabatic expansion(绝热膨胀) Process 3-4: isothermal compression (等温压缩) Process 4-1: adiabatic compression(绝热压缩)
SHANDONG UNIVERSITY6-7 The Carnot Cycle(卡诺循环)：Reversibleisothermalexpansion(可逆等温膨胀）：一Process 1-2:isothermal expansion(等温膨胀)- Tμ=constant- Gas expands slowly, doing work on surroundings, T isgoing to decrease一QissuppliedtomaintainTμ=constant（定温吸热)(1)(2)EnergyIsuonsourcealTH工QH(a)Process1-2
SHANDONG UNIVERSITY 6-7 The Carnot Cycle (卡诺循环) • Reversible isothermal expansion(可逆等温膨胀)： – Process 1-2: isothermal expansion(等温膨胀) – TH=constant – Gas expands slowly, doing work on surroundings, T is going to decrease – QH is supplied to maintain TH=constant (定温吸热) 12