Effect Of Dust On Engine Performance

You're too late. It's already been done.

How would an "air pre-filter" be different from an air filter?

Lyn,

Many trucks and most farm machinery run air pre-filters. These either spin out and drop the majority of the dust into a container or discharge it away from the primary air intake.

They do this to extend the life of the air filter element in a dusty environment.

Without the Pre-filter the main element would need to cleaned, if not replaced every day in dusty environments. The pre-filter does not wear out and extends the life of the main element many times over.

One maker you could look at for more detail (there are many others) is Donaldson.

I bet you have to make your own hypothesis and have it your way an empirical formula.

Common sense tells you, dust makes your combustion inefficient, therefore, I assume you must have taken basic mathematics and physics, then it would be that the rate of dust per charge is directly proportional to the loss of power, to find your empirical formula right there, you need to test your assumption, have some actual experiment and record the observation. From the data you have acquired, plot both parameter vs.(graph) one another, then you must find some significant correlation right there, then the relationship of both will then be your empirical formula.

And your project is done..ahm, pretty sure you need some budget to do that.

thank you Noudge, i was thinking of doing the same. but for that i would need to fabricate it. my profs require me to submit a draft on paper/ppt before i get to that, as they will be funding me. hence, the problem. is there absolutely any data out there that i can use?

Well, you can google it for some related literature. I am not quite sure there is. Your project could be of little importance compares to the effect of water/rain/snow to jet engine, because its not common to drive a car from a very dusty environment without pre-filter.

Well, good luck.

Particle size is directly proportional to how fast you want the engine to be destroyed. If you want longevity then you want particles 0 mm or less. If you want a short life-span, a singlr particle of 500 Kg released from a height of 1 M should be sufficient.

<...particles 0 mm or less...>

Absolutely!

What? I have a jar full of particles that size. Oh darn, the jar imploded.

beside the engine damage. the air to fuel ratio would be your major concern. the weight of intake air minus the weight of dust+the weight of the gasoline entering the engine should determine the air to fuel ratio. or are you asking the preformance of the air cleaner. that will depend on cylinder volume x rpm vs air flow through the filter. the difference between a clean to very dirty air filter can be measured on a flow bench.

i think i understand the ? now. the volume of the air intake " engine displacement x rpm" without an air cleaner would be the best air flow that can be expected. air filters tend to limit air flow to the engine. the size of the dust particals the filter can trap along with the area of the filter element plus the air flow should give you a mathicmatical figure you can work with.

It seems to me that dust impedes engine performance by reducing air flow through the filter. There is no appreciable performance impact of combustion air with dust in it versus combustion air without dust in it, except in the dramatic decrease in lifespan that occurs when dust is introduced into an IC. There is a lot of research on restricted airflow impact on performance.

good luck, and let me know if you disagree.

One thing to consider is the airflow capacity of the air filter assembly in a new condition relative to the airflow requirements of the engine. The same sized air filter used on a 5.0 liter engine and on a 7.4 liter engine. The first 15% air flow restriction might not affect the 5.0, while the firs 5% might cause dramatic changes on the 7.4.

Good luck.

You are trying to re-learn something that was a common application back before paper air filters were invented for IC engines.

The 'air filter' housing was a steel canister that either sat on the carb or was located remotely in the vehicle. It had an oil bath trough that completely encircled the the perimeter of the canister with an opening all the way around on the bottom.

As the air entered, it created a vortex that caused the dust laden air to hit the top of the oil bath, thereby causing the dust particles to stick to the surface of the oil as the air was being drawn into the carb. Combined with a paper filter and a centrifigal intake you would get this:

Not quite,

The pre-cleaner either drops the dust in a catch bowl or spits it back out away from the air intake.

The oil bath was the precursor of the paper or oiled foam filter. It bubbled the intake air through the oil by various means, and was very effective, but also very messy.

One of my previous cars had an an oil bath filter, one current car has a pre-cleaner followed by either an oiled foam or dry paper element depending on the owner's choice.