Courses

Gas Exchange Processes of Thermal Engines

General

Course Contents

Thermodynamics of gas-turbine cycles, gas power systems, Brayton cycle
Dimensional analysis and performance laws, flow coefficient and stage loading, specific speed and specific diameter
Diffusion and diffusers
Design methods for radial flow turbomachines
Combustion in spark‐Ignition engines, thermodynamic analysis, computation of fuel burning rates by analysis of indicator diagram
Flame structure, propagation, engine knock
Combustion in diesel engines, IDI and DI combustion chambers
Ignition delay
Heat transfer in reciprocating engine cooling systems, computation of thermal loading of engine components (piston, cylinder head, cylinder liners, exhaust valves
Charge motion within the cylinder
Gas exchange processes, flow through valves and ports
Supercharging and turbocharging a reciprocating internal combustion engine

Educational Goals

After successful completion of the course, the student should be able to:
-understand why turbomachine blades are shaped like they are
-appreciate the basic fundamentals of sensibly scaling turbomachines that are larger or smaller than a prototype
-understand the basics of combustion (pre-mixed and diffusion flames in the various types of engine combustion chambers)
-understand the flow in the cylinder, flow through valves and ports, the role of turbulence
-be introduced to more advance engineering work involving engine thermodynamics, fluid mechanics and heat transfer

General Skills

Research, analysis and synthesis of data and information, Adaptation to new situations, Decision making, Autonomous work, Exercise criticism and self-criticism, Promoting free, creative and inductive thinking.

Teaching Methods

Lectures, Exercises, Online guidance, Projected Presentations, E-mail communication, Online Synchronous and Asynchronous Teaching Platform (moodle).

Students Evaluation

Assessment Language: Greek
The final grade of the course is formed by 70% by the grade of the theoretical part and by 30% by the grade of the laboratory part.
1. The grade of the theoretical part is formed by a written final examination. The written final examination of the theoretical part may include: Solving problems of application of the acquired knowledge, Short answer questions etc.
2. The examination of the Laboratory Exercises is carried out with the continuous evaluation of the laboratory skills and the theoretical knowledge that were acquired in the course by the method of continuous evaluation and submission of weekly assignments.

Recommended Bibliography

1. N. Watson and M.S. Janota: Turbocharging the Internal Combustion Engine. Macmillan Press, 1982.
2. Turton R.K.: Principles of Turbomachinery, 2nd Ed. Chapman & Hall. London, 1995.
3. Lewis R.I.: Turbomachinery Performance Analysis, Arnold Wiley, 1996.