Fuels and Engine efficiency Mechanical Engineering

1. Jul 31, 2014

ra180

1. The problem statement, all variables and given/known data

Car (A) C180K WITH A 1.8 litre supercharged spark ignition, Maximum power output 104kw, based upon standard fuel efficiency test a vehicle with this engine would consume 6.1 liters over 100k journey

Car (B) C220 CDI with a 2.0 litre turbocharged diesel engine. Maximum output =109kw, based upon the standard fuel efficiency test a vehicle with this engine would consume 5.7 liters of Diesel over a 100km journey.

QUESTION: Calculate average fuel energy consumed per kilometer in the standard fuel efficiency test for each vehicle and hence determine which version of the vehicle had the most fuel efficient engine

2. Relevant equations

Convert miles per 100km to miles per gallon= 100*lpg/ kmpm*lp100km

lpg= litre per gallon= 4.54609188

kmpm= kilometers per mile= 1.609344

lp100km= litre per 100km

Variables given 1 mile = 1.609 km, 1 gallon = 4.546 litre

3. The attempt at a solution

Convert miles per 100km to miles per gallon= 100*lpg/ kmpm*lp100km

For Car A= 46.30 Car B = 49.56

Car (A) 104000 x 1800 = 187200000

187200000/ 1x10^6 =187.2

E gasoline = 187.2/(46.30 x 1.609km x 1/4.564)

E= gasoline= 11.47MJ/km < ANSWER

I DON'T WANT WASTE TIME ILL TRY CAR B WHEN I'M SURE MY STEPS ARE RIGHT FOR CAR A

2. Jul 31, 2014

rude man

Why convert fro nice SI units to British/American units?

3. Aug 3, 2014

ra180

I needed to convert it for my equation. Is my answer correct or not?

4. Aug 3, 2014

SteamKing

Staff Emeritus
What equation?