1. Exhaust System

2. Exhaust system components: 1-Catalytic Converter 1-Catalytic Converter 2-Muffler 2-Muffler 3-Resonator 3-Resonator 4-Tail pipe 4-Tail pipe

3. Catalytic converter Came about in 1975. Came about in 1975. It converts harmfull pollutants into less harmful emissions. It converts harmfull pollutants into less harmful emissions.

4. The main emissions of acar engine 1-Nitrogen gas (N 2 ) 1-Nitrogen gas (N 2 ) ِ Air is 78-percent nitrogen gas. 2- Carbon dioxide (CO 2 ) This is aproduct of combustion, the carbon in the fuel bonds with the oxygen in the air. 3-Water vapor ( H 2 O) This id aproduct of combustion, the hydrogen in the fuel bonds with the oxgen in the air.

5. Catalytic converter are designed to reduce all three 1- carbon monoxide (co) 1- carbon monoxide (co) Is apoisonous gas that is colorless and odorless. 2- Hydrocarbons or volatile organic compounds (Vocs) 2- Hydrocarbons or volatile organic compounds (Vocs) Are major component of smog. 3- Nitrogen oxides (NO and NO 2 called Nox) 3- Nitrogen oxides (NO and NO 2 called Nox) Are a contributor to smog and acid rain.

6. Catalytic converter structure There are two different types of catalyst at work 1- a reduction catalyst. 2- and an oxidation catalyst. Both types of aceramic structure coated with a metal catalyst,usually platinum, rhodium and or palladium.

7. How catalytic converter work A- The Reduction catalyst. A- The Reduction catalyst. Is the first stage of the catalytic converter, it usesplatinum and rhodium to help reduce the nox emission. B-The oxidation catalyst B-The oxidation catalyst is the second stage of the catalytic converter. It reduces the unburned hydrocarbons and carbon monoxide. C- Control system (O 2 sensor ) C- Control system (O 2 sensor ) that monitors the exhaust stream, and uses this information to control the fuel injection system. fuel injection systemfuel injection system

8. The catalytic converter works efficiently at afairly high temperature We can reach this By : 1- move the catalytic converter closer to the engine. 1- move the catalytic converter closer to the engine. 2- preheating the catalytic converter. 2- preheating the catalytic converter.

9. Catalytic converter in diesel engines Do not work as well in reducing Nox.

10. 2- Muffler Cancel out most of an engine ’ s noise.(sound wave). Cancel out most of an engine ’ s noise.(sound wave).

11. Where Does the sound come from ? Pulses are created when an exhaust valve opens and a burst of high – pressure gas suddenly enters the exhaust system. Pulses are created when an exhaust valve opens and a burst of high – pressure gas suddenly enters the exhaust system.

12. How can you cancel out sounds? If the first wave is at its maximum pressure, the second wave is at its minimum. If the first wave is at its maximum pressure, the second wave is at its minimum. If both of these waves hit your ear drum, you wouldnot hear anything.

13. Inside a Muffler

14. Resonator

15. Common problems: 1- corrosion … or more commonly known as Rust 1- corrosion … or more commonly known as Rust 2- short trips. 2- short trips. 3- oxygen sensor wearing. 3- oxygen sensor wearing. 4-The rust in the muffler. 4-The rust in the muffler. 5- the catalytic converter will become clogged. 5- the catalytic converter will become clogged.

16. References : http://auto.howstuffworks.com/turbo.htm http://auto.howstuffworks.com/turbo.htm http://auto.howstuffworks.com/turbo.htm http://auto.howstuffworks.com/muffler.htm http://auto.howstuffworks.com/muffler.htm http://auto.howstuffworks.com/muffler.htm