 Ch 8. Gas Power Cycle Multimedia Engineering Thermodynamics OttoCycle DieselCycle
 Chapter 1. Basics 2. Pure Substances 3. First Law 4. Energy Analysis 5. Second Law 6. Entropy 7. Exergy Analysis 8. Gas Power Cyc 9. Brayton Cycle 10. Rankine Cycle Appendix Basic Math Units Thermo Tables Search eBooks Dynamics Statics Mechanics Fluids Thermodynamics Math Author(s): Meirong Huang Kurt Gramoll ©Kurt Gramoll THERMODYNAMICS - CASE STUDY Introduction Presentation During Max's presentation of his senior capstone design project, someone asks him about comparisons between spark-ignition (SI) engine and compression-ignition) CI engine. What is known: The displacement volume of each cylinder is 1.0 L. The crankshaft rotates at 2600 RPM. The clearance volume is 15% of the volume when the piston is at the bottom dead center (BDC). The pressure and temperature of the gas-fuel mixture just before compression are: P = 100 kPa and T = 15oC The maximum temperature the engine cylinder can tolerate is T = 1800oC. Question Determine the thermal efficiency and compression ratio using the ideal Otto-cycle model. For the same temperature limits and equal amounts of heat input, which air-standard cycle has a higher thermal efficiency, Otto or Diesel? Which one has the higher compression ratio? Approach Model the cycle of this engine as an air-standard Otto-cycle and Diesel-cycle, respectively. Calculate their thermal efficiencies and compression ratios.