How to calculate fuel to accelerate a vehicle

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To calculate the fuel needed to accelerate a vehicle, one must consider both the change in potential energy due to incline and the change in kinetic energy. The energy required for potential energy can be calculated using the formula W = mgh, while kinetic energy is calculated as W = 1/2 mv^2. Fuel efficiency is a critical factor, with gasoline engines typically converting about 20% of the energy from fuel into usable power. For modern diesel engines, an average output is around 18 to 20 horsepower per gallon of fuel burned per hour. Understanding these principles will help in accurately estimating fuel consumption during acceleration.
IMK
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Hello,
I am trying to calculate how much fuel (petrol/diesel/LPG) it takes to accelerate a vehicle and well to cut a long story sort I seem to be getting my units mixed up also whether I should us small or big calories. Lastly is the incline and issue that I also need to consider and how do I apply it please?

So was wondering if someone could get me off in the right direction please?

Many thanks in advance

PS This is NOT a home work question!
 
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For gasoline, oxidation of 1 gram releases about 44,000 Joules of heat. For 1 U.S. gallon, 120 million joules. But a conventional spark-ignited internal combustion engine, the conversion efficiency is typically ~20%.

The attached thumbnail of a brake specific fuel consumption (BSFC) plot shows the efficiency of a typical 2.7-L gasoline engine as a function of RPM and torque.

Bob S
 

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If you are accelerating a vehicle up an incline, the resultant HP used is the change in potential energy plus the change in kinetic energy. Assuming you start from a standstill and zero reference position:

for the potential energy, W = mgh; for the KE energy, W = K= 1/2mv
and velocity (v) is at.

So you should expect to consume more fuel for greater height (steeper incline) and/or greater acceleration.

You'll also have to get an estimate of fuel consumption to produce a HP...that depends on the type of fuel, such as gas or diesel, type of engine, and a lot of other factors...but a reasonable average for modern diesel engines is that they produce 18 to 20 hp per gallon of fuel burned per hour.
 
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