Q$2.$ A four$-$cylinder four$-$stroke spark ignition engine with $80$ mm bore and $90$ mm stroke runs at $4000$ rpm and uses a fuel having $84\%$ carbon and $16\%$ hydrogen by mass. The volumetric efficiency of the engine at that speed is $80\%.$ The ambient conditions are: pressure $=\frac{1\mathrm{.}0}{b}ar,$ temperature $=25C.$ The depression at the venturi throat is $0\mathrm{.}06$ bar. The actual quantity of air supplied is $0\mathrm{.}95$ of the stoichiometric value. Calculate the fuel flow rate, the air velocity at the throat and the throat diameter. $(R(air)=287\frac{J}{kgK}$; R $($fuel vapour$)=98\frac{J}{kgK}.$

$($Ans: mdot$\_$f $=0\mathrm{.}003792k\frac{g}{s},V2=102\mathrm{.}5\frac{m}{s},d2=24\mathrm{.}7mm)$