5

a) Explain qualitatively how laminar burning velocity for a particular fuel varies with initial temperature, stoichiometry, pressure and oxygen concentration.

b)Define the term auto-ignition temperature (AIT). AIT tests are usually conducted according to ASTM E659 Standard. Explain the test method for a liquid fuel using this standard.

5c)What is the reason most longer chain alkanes such as those contained in gasoline (e.g. n-heptane) have lower AITs than hydrogen or methane? In your answer you should refer to additional low temperature branching routes that occur for typical longer chain alkane fuels.