1. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net CONVENTIONAL FUELS Carlos Sousa AGENEAL, Local Energy Management Agency of Almada

2. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net DIESEL AND PETROL ENGINES 4 Stroke Cycle Main components Auxiliary Systems

3. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net DIESEL 4 Stroke Cycle INTAKE Air enters the combustion chamber

4. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net COMPRESSION With all the valves closed, the piston goes up, compressing the air inside the cylinder Increase in air temperature and pressure DIESEL 4 Stroke Cycle

5. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net INJECTION The fuel is injected into the cylinder at high pressure, after the compression of the air DIESEL 4 Stroke Cycle

6. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net EXPANSION The fuel inflames when it contacts with the hot air The mechanical delivered the engine is now generated DIESEL 4 Stroke Cycle

7. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net EXHAUST After the combustion, the hot gases leave the cylinder through the exhaust valve(s) DIESEL 4 Stroke Cycle

8. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net INTAKECOMPRESSIONEXPANSIONEXHAUSTINJECTION COMBUSTÃO DIESEL 4 Stroke Cycle

9. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net Compression Ratio =

10. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net MAIN COMPONENTS OF THE ENGINE

11. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net Piston – Transmits the movement to the rod Connecting Rod – Transmits the movement to the cranshaft Crankshaft – Transforms the alternative movement in circular movement MAIN COMPONENTS OF THE ENGINE

12. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net

13. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net

14. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net

15. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net Distribution (opening / closing of the valves) Cooling system (prevents components from overheating) Lubrication (reduces sheer, washes components, etc.) Fuel (fuel intake) MAIN AUXILIARY SYSTEMS

16. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net Double OverHead Cam, DOHC Lateral Cam DISTRIBUTION

17. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net DISTRIBUTION

18. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net Objectives COOLING SYSTEMS 1. Cool engine components:  keep the engine at a suitable operating temperature (i.e. prevent the melting of components)  keep the physical and chemical proprieties of the lubricating oil (can deteriorate with exessive temperature) 2. Provide heat to acclimatize the interior of the vehicle 3. Improve cold start

19. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net Water pump Thermostat Radiator Fan Heating system COOLING SYSTEMS

20. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net The function of the engine oil is much more than lubricating. The oil must also have: High detergent and dispersant power High anti-oxidation power Good cooling capacity (contributes to engine cooling) Good capacity to neutralize acids Maintain its with temperature change (cold and hot) LUBRICATING SYSTEM

21. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net LUBRICATING SYSTEM

22. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net FUEL SYSTEM Objective: Introduce fuel in the engine, that will mix with the hot air inside the cylinder, evaporate, auto-inflame and burn

23. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net 1. Indirect injection 2. DIRECT INJECTION Direct injection in the cylinders Higher injection pressures More expensive and demanding technology Multiple jet injectors FUEL SYSTEM

24. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net DirectIndirect Losses Lower thermal losses High thermal losses between chambers Performance HigherLower Speed Slow engine speedHigher engine speed Fuel Demands higher quality fuels Works with lower quality fuels (viscosity, cetane number) Injection Multi-jet (higher injection pressure) Single-jet (lower injection pressures) DIRECT INJECTION vs. INDIRECT INJECTION

25. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net AdvantagesInconvenients Lower fuel consumptionPrice PowerNoise Cold startVibration DIRECT INJECTION vs. INDIRECT INJECTION

26. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net DIRECT INJECTION

27. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net Squish and Swirl DIRECT INJECTION

28. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net TYPES OF INJECTION SYSTEMS Radial and in-line pump Injector-pump Common Rail

29. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net TYPES OF INJECTION SYSTEMS In-line pump 600...700 bar  1 000 bar at the tip of the injector

30. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net TYPES OF INJECTION SYSTEMS Radial pump 1 000 to 1 500 bar at the tip of the injector

31. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net INJECTION SYSTEMS Advantages No high-pressure fuel lines Higher injection pressures Lower fuel consumption Better torque and power at low engine speeds Injector Pump  2000 bar

32. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net Pressão máx. 1350 – 1500 bar INJECTION SYSTEMS Common-Rail 1 800  2 000 bar Advantages Better injection control Reduction of noise and vibration Good fuel consumption Good torque and power Reduction of pollutant emissions

33. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net INTAKE IN PETROL ENGINES A petrol engine can admit: A mixture of air and fuel Air, with the fuel being injected directly into the cylinder – Direct Injection Engines Source: Total

34. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net TURBOCHARGING Objective: Increase the power/weight ratio A compressor increases the density of the air before being admitted to the cylinders Disadvantages (relative to atmospheric engines - “non-turbo”): Higher complexity and cost Higher physical and thermal strains on the engine Advantages: More torque and power Better fuel consumption

35. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net TURBOCHARGING

36. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net TURBOCHARGING

37. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net Variable geometry More torque over all engine speed range Better fuel consumption More power TURBOCHARGING

38. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net TURBOCHARGING INTERCOOLER Objective: Increase the power/weight ratio Cools the air after the compression, before admitting it to the cylinders: Higher mass of air inside the cylinders More fuel More torque More power

39. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net POLLUTANTS FORMATION AND CONTROL Combustion in Diesel engines is characterised by a high concentration of fuel droplets (poor atomization/vaporization of the fuel). Main pollutants: Particulate Matter (PM) Unburned Hydrocarbons, HC Carbon Monoxide, CO Nitrogen Oxides, NO x

40. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net POLLUTANTS FORMATION AND CONTROL Emissions control: Exhaust Gas Recirculation, EGR Particulate Filters Catalytic Converters

41. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net POLLUTANTS FORMATION AND CONTROL Emissions control Diesel: Exhaust Gas Recirculation, EGR (prevents the formation of NO x ) Particulate Filters, active and passive (PM) Oxidation Catalytic Converters (HC and CO) Selective Catalytic Reduction, SCR (NO x into N 2 and H 2 O) Petrol: 3-way Catalytic Converters Oxidation Catalysts (CO and HC into CO 2 and H 2 O) Reduction Catalysts (NO into N 2 and O 2 )

42. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net Fuel Quality, Diesel: Diesel is cetane derived (C 10 H 22 ) Cetane Number: Indicates the higher or lower capacity of the fuel to auto- ignite (  lower delay to auto ignition) 15: Low capacity to auto-ignite: isocetane 100: High capacity to auto-ignite: cetane Minimum cetane number demanded: 51 Sulphur content: Less than 50 ppm  Low sulphur fuel Eliminate emissions of sulphur dioxide (SO 2 ) Reduce PM emissions Less than 10 pmm: Sulphur free fuel (From 2009)

43. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net

44. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net HCCONO x PM Diesel Petrol POLLUTANTS FORMATION AND CONTROL

45. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net EUROPEAN EMISSIONS STANDARDS StandardYearCOHCHC + NO x NO x PM Euro 119922.72-0.97-0.14 Euro 2 - IDI19961.00-0.70-0.08 Euro 2 - DI19991.00-0.90-0.10 Euro 320010.64-0.560.500.05 Euro 420050.50-0.300.250.025 Diesel Passenger vehicles  2.5t (values in g/km)

46. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net ENERGY EFFICIENCY TORQUE Energy generated in one revolution of the engine, resulting from the combustion of the fuel [kg.m or N.m]. 1 kg.m=9.8 N.m The higher the torque, the more efficient is the engine for a given engine speed. POWER Energy generated per unit of time [W or CV]. 1kW = 1,36 CV 1 CV = 0,736 kW

47. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net ENERGY EFFICIENCY Torque curve Shows the torque distribution along the entire engine speed range, at full engine charge (full throttle). Should be as flat as possible, which means good engine response at all engine speeds. RPM x N.m (or kg.m)

48. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net ENERGY EFFICIENCY Power curve Shows the power distribution along the entire engine speed range, at full engine charge (full throttle). RPM x kW (or CV)

49. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net ENERGY EFFICIENCY CO 2 emissions per litre: Petrol a little lower Diesel CO 2 emissions per km: Diesel uses less fuel... …emits less CO 2 Energy efficiency is a function of the compression ratio Diesel engines use variable fuel to air ratios Petrol engines use a constant air to fuel ratio (stoichiometric: 14.7 to 1), no matter what the speed and load are Diesel engines have an unthrottled intake and the air to fuel ratio at idle speed can go as low as 100 to 1, thus giving a much greater partial load fuel efficiency than petrol engines

50. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net ENERGY EFFICIENCY Compression ratio Theoretical engine efficiency Diesel engines Petrol engines

51. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net ENERGY EFFICIENCY Useful work Ideal process Stoichiometric losses Combustion losses Speed variations Losses Friction losses Losses 87% Petrol engine, urban driving

52. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net DIESEL vs. PETROL DieselPetrol Admission AirAir and fuel Combustion Auto ignition, due to the high pressure and temperature inside the cylinder Spark ignition Fuel Must vaporize easily and auto-ignite (high cetane number) Must be resistant to auto- ignition (high octane number) Compression ratio Highest possible (15 to 24) Limited by fuel characteristics (9 to 12) Efficiency ~35%Less than 30% Turbo charging Whenever possible. Increases efficiency and improves combustion Not common, but is becoming a popular solution

53. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net DIESEL vs. PETROL DieselPetrol Fuel consumption LowerHigher Fuel price Usually lower, but depends on the taxes applied in each country Higher Weight HeavierLighter and more compact Start Almost immediateImmediate Vibration and noise HighLow Engine speed Limited by the characteristics of the cycle and fuel High

54. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net CAR INDUSTRY – ONE CURIOSITY In 1976, Volkswagen came up with the designation “GTI”, but did not register it. Almost all auto makers used it!! But, in 1991, Volkswagen came up with the designation “TDI” and registered it. The result was…

55. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net CAR INDUSTRY – ONE CURIOSITY TDI – VAG GroupTiD - Saab JTD - Alfa, Fiat, LanciaD- 4D - Toyota d - BMWD5- Volvo CRD - Chrysler, JeepHDI - Peugeot, Citroën TDdi - FordDi-D – Mitsubishi TDCi - ForddTi - Renault CDTi - HondadCi - Renault CRDi - HyundaiCDT – Rover DvTdi – Mazda DTI – Opel DiTD – Mazda CDI – Mercedes DDTi – Nissan

56. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net Summary Advantages Diesel engines: Better energy efficiency: Use less fuel/energy (work with higher compression ratios) Advantages Petrol engines: Better cold start Less noise and vibrations More elasticity (higher engine speeds) Lighter More power for the same engine size

57. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net Summary Investments in Diesel engines/technology intend to: improve atomization of the fuel (higher injection pressures) improve flow inside the cylinder optimize injection to reduce noise and vibration maximize power and torque without sacrificing fuel consumption (optimize turbo charging) optimize fuel injection to reduce fuel consumption (e.g.: injection technologies)

58. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net Oil companies are working to: Increase cetane number Lower sulphur content Summary

59. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net Thanks to Prof. Tiago Farias Technical University of Lisbon

60. ALTERNATIVE FUELS AND VEHICLES www.transportlearning.net Thank you for your attention!