2. TYPES OF ENGINE COOLING SYSTEMS
Typical gasoline engine cooling system
Air-cooled aircraft engine
3. ADVANTAGES OF A PRESSURISED
THERMO-SYPHON SYSTEM
• Better thermal efficiency allowing the engine to run at a
higher temperature
• Smaller system required
• Reduces water loss from vapourisation
• Engine can operate efficiently at high altitudes
5. PETROL, DIESEL OR…?
WHICH HEAT ENGINE?
• Torque
• Efficiency
• Combustion temperature
• Lubrication required
6.
7. HEAT LOAD
𝑞 = 𝑚 ∙ 𝑐𝑝 ∙ ∆𝑇
Where: q is the heat load in BTU/min
m is the mass flow rate of the coolant in BTU/(lb⋅F)
𝑐 𝑝 is the specific heat capacity in kJ/kgK
∆𝑇 is the drop in temperature at the radiator in F
8. HEAT LOSSES
𝑄𝑙𝑜𝑠𝑠 = 𝑄 𝑐𝑜𝑜𝑙𝑎𝑛𝑡 + 𝑄 𝑜𝑖𝑙 + 𝑄 𝑎𝑚𝑏𝑖𝑒𝑛𝑡
• Combustion chamber
• Gas to cylinder walls
• Cylinder walls
• Coolant
• Pipework and engine
• Engine materials to air
9.
10. METHODS OF IMPROVEMENT
• Better insulation
• Lower heat production
• Better flow (air and
coolant)
• Better heat removal
• Alternative fuels
• Alternative coolant fluids
