How to calculate fuel to accelerate a vehicle

In summary, the conversation discusses the calculation of fuel consumption for accelerating a vehicle, taking into consideration factors such as incline and efficiency of the engine. It is noted that for gasoline, 1 gram releases 44,000 Joules of heat and a conventional spark-ignited internal combustion engine has an efficiency of ~20%. The conversation also mentions the use of a brake specific fuel consumption (BSFC) plot to determine engine efficiency. Additionally, the effect of incline on fuel consumption is discussed, with the conclusion that greater height and acceleration result in higher fuel consumption. The conversation ends by mentioning the need for an estimate of fuel consumption to produce a certain amount of horsepower, with an average of 18-20 hp per gallon of fuel
  • #1
IMK
63
0
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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  • #2
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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  • #3
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.
 

1. How do you calculate the amount of fuel needed to accelerate a vehicle?

To calculate the fuel needed to accelerate a vehicle, you can use the following formula:

Fuel = (Vehicle Mass x Acceleration) / Fuel Efficiency

This formula takes into account the weight of the vehicle, the desired acceleration, and the fuel efficiency of the vehicle.

2. What is the vehicle mass and how do you determine it?

The vehicle mass refers to the weight of the vehicle, including any passengers or cargo. This can typically be found in the vehicle's manual or by using a scale to weigh the vehicle.

3. How do you determine the acceleration of a vehicle?

Acceleration is the rate at which the velocity of a vehicle changes over time. To determine the acceleration, you can use a speedometer or GPS device to measure the change in speed over a specific period of time.

4. What is fuel efficiency and how do you find it?

Fuel efficiency, also known as fuel economy, is the measure of how far a vehicle can travel with a certain amount of fuel. It is typically expressed in miles per gallon (MPG) or liters per 100 kilometers (L/100km). You can find the fuel efficiency of a vehicle in the owner's manual or by researching the make and model online.

5. Are there any other factors that can affect the calculation of fuel needed to accelerate a vehicle?

Yes, there are other factors that can affect the calculation of fuel needed to accelerate a vehicle. These may include driving conditions (such as stop-and-go traffic or inclines), weather conditions, and the type of fuel used. Additionally, factors such as air resistance and rolling resistance can also impact fuel consumption.

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