What factors affect fuel consumption and speed in road vehicles?

In summary, the conversation is about the amount of fuel used for a given journey when traveling at different speeds. The speaker has assumed that fuel consumption is proportional to engine power and is only considering air drag, ignoring rolling resistance. They have used power * time as a measure for total fuel used and are seeking feedback. They also recommend a book, "Road Vehicle Performance: Methods of Measurement and Calculation" by George Gordon Lucas, specifically volume 7, for further study on the subject.
  • #1
dean barry
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I was wondering about the amount of fuel used for a given journey.
My model is that the same journey is made at two different constant speeds
I have assumed that instantaneous fuel consumption is proportional to the power produced by the engine at that point.
I an ignoring rolling resistance losses, and considering air drag only.
I have used power * time as a base for total amount of fuel used for each journey
Any comments ?
 
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1. How does speed affect fuel consumption?

As a general rule, the faster you go, the more fuel your vehicle will consume. This is because higher speeds require more energy to overcome air resistance and maintain constant acceleration. Additionally, driving at higher speeds often requires frequent braking and accelerating, which can decrease fuel efficiency.

2. What is the optimal speed for fuel efficiency?

The optimal speed for fuel efficiency varies depending on the vehicle and driving conditions, but in most cases, it is around 50-60 miles per hour. This is because most vehicles are designed to operate most efficiently at these speeds and driving at a constant speed without frequent braking and accelerating can improve fuel efficiency.

3. Is fuel consumption affected by other factors besides speed?

Yes, fuel consumption can be affected by several other factors including vehicle weight, engine size, and driving habits. Vehicles that are heavier or have larger engines typically consume more fuel, and aggressive driving habits such as sudden acceleration and braking can also decrease fuel efficiency.

4. How can I improve my vehicle's fuel efficiency?

To improve fuel efficiency, you can try driving at a constant speed, avoiding aggressive driving habits, and properly maintaining your vehicle. Additionally, using cruise control on the highway and keeping your tires properly inflated can also help improve fuel efficiency.

5. Does fuel consumption increase with the use of air conditioning?

Yes, using air conditioning can increase fuel consumption as it puts extra strain on the engine. However, at higher speeds, the use of air conditioning may be more efficient than driving with the windows down, as open windows can create drag and decrease fuel efficiency. It is recommended to use air conditioning sparingly to balance comfort and fuel efficiency.

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