1. A EROSPACE E NGINEERING L ABORATORY (MAE308) P ROF. S EUNG W OOK B AEK Department of A EROSPACE E NGINEERING, KAIST, IN KOREA R OOM : Building N7-2 #3304 T ELEPHONE : 3714 swbaek@kaist.ac.kr http://procom.kaist.ac.kr T A : Hyungjin Ahn R OOM : Building N7-2 #1304 T ELEPHONE : 5754 nicedays22@kaist.ac.kr P ROF. S EUNG W OOK B AEK Department of A EROSPACE E NGINEERING, KAIST, IN KOREA R OOM : Building N7-2 #3304 T ELEPHONE : 3714 swbaek@kaist.ac.kr http://procom.kaist.ac.kr T A : Hyungjin Ahn R OOM : Building N7-2 #1304 T ELEPHONE : 5754 nicedays22@kaist.ac.kr

2. P ROPULSION AND C OMBUSTION L ABORATORY A EROSPACE E NGINEERING L ABORATORY MAE 308 C ONTENTS 1. Objectives 2. Background 3. Experimental setup 4. Isothermal, Adiabatic process 5. Thermodynamic relation P ROPULSION AND C OMBUSTION L ABORATORY A EROSPACE E NGINEERING L ABORATORY MAE 308 Understanding of polytropic process by using RCM

3. P ROPULSION AND C OMBUSTION L ABORATORY A EROSPACE E NGINEERING L ABORATORY MAE 308 operation with various gases estimation of thermodynamic process Polytropic process using the RCM Objective Determination of specific heat ratio index RCM operation with air by varying operation speed Week 1Week 2

4. P ROPULSION AND C OMBUSTION L ABORATORY A EROSPACE E NGINEERING L ABORATORY MAE 308 Background What is RCM?(Rapid compression machine) Application → Experimental simulator of HCCI (Homogeneous Charge Compression Ignition) → Single compression stroke → Combustion experiment → Analysis of product gas

5. P ROPULSION AND C OMBUSTION L ABORATORY A EROSPACE E NGINEERING L ABORATORY MAE 308 Experimental setup

6. P ROPULSION AND C OMBUSTION L ABORATORY A EROSPACE E NGINEERING L ABORATORY MAE 308 Isothermal process

7. P ROPULSION AND C OMBUSTION L ABORATORY A EROSPACE E NGINEERING L ABORATORY MAE 308 Adiabatic process

8. P ROPULSION AND C OMBUSTION L ABORATORY A EROSPACE E NGINEERING L ABORATORY MAE 308 Isothermal, Adiabatic process Carnot cycle Isothermal process during heat exchange Isentropic compression and expansion Heat in Heat out Isentropic compression Isentropic expansion Isothermal Heat in Isothermal Heat out

9. P ROPULSION AND C OMBUSTION L ABORATORY A EROSPACE E NGINEERING L ABORATORY MAE 308 Isothermal Adiabatic 9 0<t<∞ t → ∞ Polytropic t → 0 State 1.State 2. Operation time Thermodynamic relation P peak1 > P peak2 > P peak3

10. P ROPULSION AND C OMBUSTION L ABORATORY A EROSPACE E NGINEERING L ABORATORY MAE 308 Heat loss through the wall… Controlling Parameters : Thermal conductivity, internal flow, operation time …. Polytropic process !! Thermodynamic relation

11. P ROPULSION AND C OMBUSTION L ABORATORY A EROSPACE E NGINEERING L ABORATORY MAE 308 n = Log CR P Peak Adiabatic Index n distribution according to time and CR at air case Operation time Vs. index n (Adiabatic) n=1.4(N2), 1.667(Ar) (Isothermal) n=1.0 (Polytropic) n = ? Thermodynamic relation Ideal case