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Mass of Particulate from fuel exhaust

  1. Jun 15, 2016 #1
    I'd like to know that apart from Gases coming out of tailpipe of a vehicle, how much is Solid particle mass exhausted per gallon of fuel? I tried to search but I couldn't get exact answer.
    e.g. After 1 gallon of fuel burnout, exhaust pipe emits 1 gm or 10 gm or 100 gm of solid particles (PM10 or similar?)?
  2. jcsd
  3. Jun 16, 2016 #2
    Diesel particulates have a bimodal size distribution which includes small nuclei mode particles and larger accumulation mode particles.

    Most of diesel particle mass is contained in the accumulation mode while most of the particle number can be found in the nuclei mode. Although the exact composition of diesel nano particles is not known, it is believed that they are composed primarily of condensates (hydrocarbons, water, sulfuric acid).

    The amount of these condensates and the number of nano particles depends significantly on the particulate sampling conditions, such as dilution ratios, which were applied during the measurement. Spark ignited engines also emit numbers of small particles which are comparable to those from diesel engines.
    This definition includes both solids, as well as liquid material which condenses ...Diesel particulates include small nuclei mode particles of diameters below 0.04 µm and ... The mass of particulate emissions is determined based on the weight of PM ... Since the atmospheric dilution ratios of PM (about 500-1000) are much ...

  4. Jun 16, 2016 #3


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    There is no one exact answer, but per the ranges you gave, 1 gm/gallon would be the closest. What, exactly, was the google search you did? I got a lot of relevant hits.
  5. Jun 17, 2016 #4
    Thank you. 1 gm/gallon was just thrown as example. I used various terms for search but couldn't find the formula or example for particular car model or so. I was wondering whether there is certain range for different vehicles, based on how much mileage they give.
  6. Jun 17, 2016 #5

    Thank you!
    So it looks like we don't have exact or approximate values published by Auto makers? They should mention that our vehicle emits this much particles and this much gas per gallon. That would be very useful info, but looks like they want to hide something and don't want to let us know.
  7. Jun 17, 2016 #6


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    AFAIK, there are no requirements for manufacturers to measure or compile data on particulate emissions for every type of vehicle.

    That said, there is much ongoing research into particulate matter being created and emitted by many newer types of engines, such as gasoline direct injection designs. The environmental agencies charged with monitoring all types of particulate emissions, from stationary as well as vehicle sources, are also involved in this research, certainly with the goal to step in and regulate such emissions when necessary.

    There's no need to formulate any conspiracy theories just yet.
  8. Jun 17, 2016 #7
    Not conspiracy theory, but how hard is it for car manufacturer to mention the PM mass / gallon at idle running condition or at some rpm? It must be very easy to measure it, right?
    Also I see GPM and DPM, are they still researching on what would be the mass of it? I see the particle numbers they claim in range. But was curious about mass in lb/gallon or so.
  9. Jun 17, 2016 #8


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    Beats me, but if you start measuring X, then some bright spark will want you to measure Y and Z also. There's only so much time you can spend fiddling on this stuff when you must get the vehicles certified for sale. If you miss that deadline, the company can lose millions of dollars in sales.

    If you have access to a car, you can try to measure how much PM comes out the tailpipe.
  10. Jun 17, 2016 #9
    Unfortunately I don't have equipment to measure it, but I guess that would be easy to measure using the GPM / DPM filters. Or in an enclosed laboratory, that could be done. Just my thoughts. But looks like it is difficult, as it hasn't been done before.
  11. Jun 18, 2016 #10


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    The equipment would not be terribly expensive. You need some sort of heat exchanger to reduce the tailpipe temperature. Then catch the particulates in a HEPA filter.

    Bake out and weigh the equipment first. Burn a given amount of fuel then bake out and weigh again. Do that at several operating points. I would guess that the dynamometer time would be your biggest expense.

  12. Apr 24, 2017 #11
    Looks like a Brown's gas generator helps burn gasoline more efficiently . My inquiries have led me to believe so . I live in Hawaii and we don't test for emissions , perhaps that data would be helpful .
    L. A. cleaned up their sky's with tight emissions control . My concern is that a lot of visible particulate matter got removed , now the population has doubled and albeit the sky is much clearer , we now have more particulate matter than before .
    Does anyone have any information about
    Browns gas/particulate emissions ?
  13. Apr 24, 2017 #12
    The vehicles are required to meet emissions standards. The emissions data is released to the EPA and is highly proprietary.

    You should research the emissions standards that vehicles have to meet in order to be eligible for lawful commercial sale in the U.S. If you knew anything about emissions testing engines, you would know that emissions are measured in grams per kilowatt-hour. Emissions are not measured on a per-gallon domain. They are not trying to "hide" anything. The emissions standards for engines in every given type, size, and application are on the public domain. You can research them yourself.

    Thermal efficiency and emissions output levels are not the same thing.

    Most people would not know how to comprehend emissions data or compare two different engine types or two different applications. THey also wouldn't understand how the rate of emissions production per kw-hr relates to the actual amount of emissions that they would generate by driving that vehicle around. Some vehicles need to make fewer kw-hrs to go from A-B than other vehicls. So one car might make more emissions per kw-hr, but generate fewer emissions on your way to work than another vehicle, because the other vehicle has to make more kw-hr to get to work. And how much emissions generated per gallon depends entirely on the duty cycle that the engine is operating at.

    The manufacturers aren't trying to "hide" anything. Its proprietary information relating to regulatory compliance. The legal department would **** a brick if their marketing team started advertising that sensitive information with today's destructive eco-fascist eco-friendlier-than-thou movements. They'd be doing nothing but opening themselves up to problems no matter how good their vehicles emissions were.
    Last edited: Apr 24, 2017
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