Automobiles And The Environment CHAPTER 3

3.1 The Automobile and Society The Sale Comparison of China and USA, Jan-March 2009 Unit: 10000

The Annual Car Production of China, Unit:

What are the major elements you will consider when you decide to buy a car? Case Study:

An Average Buyer  Price  Power --- speed, strength  Outlook --- color, profile  Oil Consumption  Safety Design \ Function  Interior Decoration--- comfort, space  Lifetime

The Priority Choice  Power  Outlook  Interior Design  Safety Function

Environmental Choice  Oil Consumption--- Fuel  Material --- quantity, types……  Emission Control --- type of pollutant, quantity….  Profile--- power, speed, oil usage… …  Energy Efficiency ……….

3.1 The Automobile and Society  Contribution of automobile(cars) An important element in modern society USA( example):  Standing a big percentage in industrial development  Responsible for the growth of suburb  Provide person freedom  A promotion to roads and traffic Traffic accidents Reverse environment impacts

3.2 Environmental Impacts of the Automobile  Urban Air pollution Major Pollutants Offsetting Factors that automobile keep on affects air quality  Increasing vehicle population  Increasing travel per vehicle  Departures from federal standards  Greater use of light trucks

 Greenhouse Gas Emission The major source lead to Global Warming Main items: CO 2,O 3,CFC S ….. Source of CO 2 :  Combustion of Fossil fuels 3.2 Environmental Impacts of the Automobile

 Material Used and Solid waste Major material used in a car:  Steel,Iron, Aluminum  Plastics,Rubber  Glass  Other material….. Mainly Non-renewable Resources 3.2 Environmental Impacts of the Automobile

 Material used and Solid waste Impacts deal with material usage  Mining for resources — land destroy; ecological damage  Refining : pollution, waste heat, energy consumption  Processing: more pollution,energy consumption  Transportation: emission, energy consumption  Manufacturing : energy consumption, pollution

 Material Used and Solid waste Major solid waste that car produced:  Metals  Combustibles  Inerts Major technology used dealing with solid waste:  Junk yard: piling waste car  Recycle technology: useful material collection  Landfill: final way for waste deposal 3.2 Environmental Impacts of the Automobile

Other Environmental Impacts  Lead emission Source? Impacts?  CFC emission Source? Impacts?  Waste Motor Oil Source? Impacts?  Other life cycle impact

3.3 Fuel and Energy Requirements  Power for Cruising 1.Moving on level ground, constant speed 2.Major barrier (force ) to over come: Friction :44% Aerodynamic drag:56% 3.Car elements related: Cross-sectional area Shape Weight F drag F friction F

 Power for Cruising  Power for Hill Climbing 1Hill climbing,constant speed 2.Major barrier (force )to over come: Friction : Aerodynamic drag: Gravity :>50% of total power 3.Car elements related: Cross-sectional area Shape Weight and material chosen 4. Additional power needed depends on : Weight and material Steepness of slope F drag F friction F W

 Power for Cruising  Power for Hill Climbing  Power for Acceleration 1 Accelerate from rest, level 2.Major barrier (force )to over come: Road friction : Aerodynamic drag: Kinetic energy change ( from rest to certain velocity) 3.Car elements related: Cross-sectional area + Shape Weight + material chosen Accelerating time + Final velocity 4. Additional power needed depends on : Weight + material Increasing speed Travel distance

3.3 Fuel and Energy Requirements Barrier need to over come Power Cruising Road friction Aerodynamic drag P cruise Hill Climbing Road friction Aerodynamic drag Gravity P hill =2P cruise Acceleration Road friction Aerodynamic drag Kinetic energy change P accel =3P cruise

3.3 Fuel and Energy Requirements 1. What is the efficiency of a car ? 60-70%: transfer into waste heat 15%: for “ standby loss ” (keep an engine idling and ready to power) Few %: auxiliary system 5%: to overcome frictional forces 15-20%: propel a car 2. What is the overall efficiency? 3.Peak Efficiency: cruising speed at 13-18m/s(30 to 40 mph)  Power for Cruising  Power for Hill Climbing  Power for Acceleration  Energy Efficiency

3.3 Fuel and Energy Requirements  Fuel Consumption Travel at constant speed Travel at constant acceleration

 Designing for Energy Efficiency Benefits deal to energy saving  Less fuel required  Less CO 2 Emission  Reduce indirect impacts  Reduce the depletion of natural resources 3.4 Engineering Cleaner Cars

 Designing factors affects energy efficiency Engine efficiency Drive train efficiency Vehicle weight Cross-sectional area Drag coefficient Rolling friction coefficient Engine size or power Velocity Acceleration

 Understanding pollution formation Air-fuel ratio:  Affected completed combustion Formation of NOx:  control of peak temperature  Alter combustion stoichiometry  Time-temperature profile 3.4 Engineering Cleaner Cars

 Designing for low-emission New kind of engine Catalytic converters  Alternative fuel Alternative fuel Diesel methanol 3.4 Engineering Cleaner Cars

 Alternative Vehicles Hybrid Vehicles V2 Hybrid Vehicles V2 Eden-Car Show 3.4 Engineering Cleaner Cars