How does the engine of a plane work?

[JtD]

It changes with temperature and composition (humidity), but not density.

[-TBC-AeroAce]

On 09/03/2018 at 9:00 AM, Ehret said:

 

A turbofan engine can go supersonic - maybe could be considered as one, as its fan resembles a propeller in duct?

 

The air going in to jets is actually subsonic. The supersonic airflow is slowed down to subsonic by the inlet of the engine.

Edited March 12, 2018 by AeroAce

[PainGod85]

On 9.3.2018 at 2:39 AM, 6./ZG26_Klaus_Mann said:

A Diesel with AdBlue Injection will literally be unable to Kill you with it's exhaust Gasses. You can take a Modenr Diesel into your Garage, close all Doors, get in it and run it for 24 Hours and come out Perfectly alive.

 

I don't think you're aware of how deadly a pure carbon dioxide atmosphere is.

 

Yes, Diesels are more efficient than electric or gasoline engines, and the whole public debate is skewed by ideology, not influenced by facts. However, the difference in efficiency is around 5-10% (Gasoline cars reach 30-35%, diesels up to 40% efficiency).

 

The facts are that 90% of the particulates they find in city centers are actually from natural sources - pollen and so forth. Nobody has died from these, as far as anyone can tell. Furthermore, the 16 largest cargo vessels produce as much particulate as all cars worldwide - but for some reason, that doesn't matter in the eye of the public.

 

Furthermore, the NOx scare is also completely stupid. In the EU you're allowed to be exposed to 23 times the NOx concentration for 8 hours every workday sitting in your office, but spending 15 minutes walking alongside traffic on your way to or from work exposed to a fraction of that concentration is somehow unhealthy. Yeah, right.

As a matter of fact, I contest the supposition that having an AdBlue system in your Diesel car (or truck) is even necessary.

Edited March 12, 2018 by PainGod85

[Pail]

On 3/13/2018 at 9:40 AM, PainGod85 said:

The facts are that 90% of the particulates they find in city centers are actually from natural sources - pollen and so forth. Nobody has died from these, as far as anyone can tell. Furthermore, the 16 largest cargo vessels produce as much particulate as all cars worldwide - but for some reason, that doesn't matter in the eye of the public.

 

Furthermore, the NOx scare is also completely stupid. In the EU you're allowed to be exposed to 23 times the NOx concentration for 8 hours every workday sitting in your office, but spending 15 minutes walking alongside traffic on your way to or from work exposed to a fraction of that concentration is somehow unhealthy. Yeah, right.

 

Aerosol particles of natural origin (such as windblown dust) tend to have a larger radius than human-produced aerosols such as particle pollution.^[11]  and people do die from them at times....

 

'Because land is concentrated in the Northern Hemisphere, the amount of small aerosols from fires and human activities is greater there than in the Southern Hemisphere. Over land, patches of large-radius aerosols appear over deserts and arid regions, most prominently, the Sahara Desert in north Africa and the Arabian Peninsula, where dust storms are common. Places where human-triggered or natural fire activity is common (land-clearing fires in the Amazon from August–October, for example, or lightning-triggered fires in the forests of northern Canada in Northern Hemisphere summer) are dominated by smaller aerosols. Human-produced (fossil fuel) pollution is largely responsible for the areas of small aerosols over developed areas such as the eastern United States and Europe, especially in their summer. '

https://en.wikipedia.org/wiki/Particulates#Size_distribution_of_particulates

 

The primary sources indoors are combustion

processes, such as unvented combustion

appliances

(e.g., gas stoves, vented appliances

with defective installations, welding, and

tobacco smoke). Outdoor sources, such as

vehicles and lawn and garden equipment, also

contribute to nitrogen oxide levels

https://www.epa.gov/sites/production/files/2014-08/documents/refguide_appendix_e.pdf

 

Indoor Nitrogen Oxides

https://pdfs.semanticscholar.org/e5bb/ed9dff7e962f5539723e1b6dc904f174092c.pdf

 

NOAA Study Shows Nitrous Oxide Now Top Ozone-Depleting Emission

http://www.noaanews.noaa.gov/stories2009/20090827_ozone.html

 

http://www.canberratimes.com.au/environment/weather/going-to-extremes-uv-radiation-is-on-the-way-up-20180307-p4z3cp.html

 

There is no doubt human caused NOx pollution and ultra fine particulate pollution is bad.

Edited March 14, 2018 by Pail
remove vacant space at the bottom

[PainGod85]

10 hours ago, Pail said:

 

Aerosol particles of natural origin (such as windblown dust) tend to have a larger radius than human-produced aerosols such as particle pollution.^[11]  and people do die from them at times....

 

'Because land is concentrated in the Northern Hemisphere, the amount of small aerosols from fires and human activities is greater there than in the Southern Hemisphere. Over land, patches of large-radius aerosols appear over deserts and arid regions, most prominently, the Sahara Desert in north Africa and the Arabian Peninsula, where dust storms are common. Places where human-triggered or natural fire activity is common (land-clearing fires in the Amazon from August–October, for example, or lightning-triggered fires in the forests of northern Canada in Northern Hemisphere summer) are dominated by smaller aerosols. Human-produced (fossil fuel) pollution is largely responsible for the areas of small aerosols over developed areas such as the eastern United States and Europe, especially in their summer. '

https://en.wikipedia.org/wiki/Particulates#Size_distribution_of_particulates

 

The primary sources indoors are combustion

processes, such as unvented combustion

appliances

(e.g., gas stoves, vented appliances

with defective installations, welding, and

tobacco smoke). Outdoor sources, such as

vehicles and lawn and garden equipment, also

contribute to nitrogen oxide levels

https://www.epa.gov/sites/production/files/2014-08/documents/refguide_appendix_e.pdf

 

Indoor Nitrogen Oxides

https://pdfs.semanticscholar.org/e5bb/ed9dff7e962f5539723e1b6dc904f174092c.pdf

 

NOAA Study Shows Nitrous Oxide Now Top Ozone-Depleting Emission

http://www.noaanews.noaa.gov/stories2009/20090827_ozone.html

 

http://www.canberratimes.com.au/environment/weather/going-to-extremes-uv-radiation-is-on-the-way-up-20180307-p4z3cp.html

 

There is no doubt human caused NOx pollution and ultra fine particulate pollution is bad.

 

 

 

 

Sigh.

 

You really didn't address any of my points.

 

1. Of the miniscule fraction of manmade particulates, the overwhelming majority isn't actually produced by cars.

 

2. The threshold of NOx concentration next to a busy street is 1/23th of what you're allowed to be exposed to for 8 hours every day at your office job. If you don't see anything wrong with this, I don't even know anymore.

 

I'm not contesting NOx is bad for the ozone layer. I'm saying the current limits in the EU are not grounded in any notable scientific data, and neither are the ones for particulates.

[ACG_HotLunch]

On 09/03/2018 at 9:09 PM, Sambot88 said:

 

Weren't the bombs dropped on Japan in 1945 dropped by propeller-driven bombers?

And there it is folks. Checkmate.

[AndyJWest]

If this thread was an aeroplane, I'd court-martial the navigator.

[Finkeren]

3 hours ago, AndyJWest said:

If this thread was an aeroplane, I'd court-martial the navigator.

 

Well, to be fair: The initial question was answered within the first few posts.

[Pail]

8 hours ago, PainGod85 said:

You really didn't address any of my points.

 

They are anti-science rubbish with no supporting evidence. Your EU standards appear made up.

 

EU Standard

Nitrogen dioxide (NO2)	200 µg/m3	1 hour	Limit value entered into force 1.1.2010	18
	40 µg/m3	1 year	Limit value entered into force 1.1.2010*

http://ec.europa.eu/environment/air/quality/standards.htm

8 hours ago, PainGod85 said:

1. Of the miniscule fraction of manmade particulates, the overwhelming majority isn't actually produced by cars.

 

" PM_2.5 particles result from the burning of fossil fuels (such as coal), organic matter (including wood and grass) and most other materials, such as rubber and plastic. Motor vehicles, power plant emissions and bushfires are all major sources of fine particles. "

 

"There are outdoor and indoor sources of fine particles. Outside, fine particles primarily come from car, truck, bus and off-road vehicle (e.g., construction equipment, snowmobile, locomotive) exhausts, other operations that involve the burning of fuels such as wood, heating oil or coal and natural sources such as forest and grass fires. Fine particles also form from the reaction of gases or droplets in the atmosphere from sources such as power plants. These chemical reactions can occur miles from the original source of the emissions.

PM_2.5 is also produced by common indoor activities. Some indoor sources of fine particles are tobacco smoke, cooking (e.g., frying, sautéing, and broiling), burning candles or oil lamps, and operating fireplaces and fuel-burning space heaters (e.g., kerosene heaters)."

 

http://www.epa.vic.gov.au/your-environment/air/air-pollution/pm25-particles-in-air

https://www.health.ny.gov/environmental/indoors/air/pmq_a.htm

 

You Have No Points.

[Vig]

On ‎3‎/‎7‎/‎2018 at 6:03 PM, Sambot88 said:

 

Now this is a post that has piqued my interest. Are there examples of planes (modern or not) that used Diesel? Or that did something to be more "Rugged"? What about B-52s and C-130s?

 

 

C-130s are supposed to use JP-8 but can use other fuels, including AVGAS, in a pinch. 

 

[Pail]

As far as pollution mapping/modelling and atmospheric or ocean conditions go, a really nice website to look at them is https://earth.nullschool.net/

Very worth checking out if you haven't seen it.

[6./ZG26_Klaus_Mann]

On 13.3.2018 at 12:10 AM, PainGod85 said:

5-10% (Gasoline cars reach 30-35%, diesels up to 40% efficiency).

35% in a Petrol Car only under very, very controlled Conditions, not daily Driving. 30% are the Average today, while modern Turbodiesels are at 45% average today (hence the NOx Problem, of them Running so hot they actually start to react with such a very Inert Gas such as Nitrogen, Hell of a Lot of Energy in the Burn). 

 

That's not a 15% Difference, that is 50% better than Petrol. 

 

The Big Ship Diesels now are achieving 50%. 

 

There is simply is no Good Reason to own a Petrol Car over a Diesel Car in an equal Environment, unless you want something light and sporty. 

Otherwise Emissions are better, Economy and Longevity are as well, only Oil Change Intervals are slightly shorter for a Turbo Diesel v NA Petrol, but the TSIs and equialents are the same as Diesel in that Department. 

 

 

Edited March 14, 2018 by 6./ZG26_Klaus_Mann

[Bladebender]

Getting back to the original topic....

 

Most engines have a rating known as the SFC - Specific Fuel Consumption.

Typically given as: Pounds(lb) / Horsepower / Hour. Reciprocating engines from the WW2 period were in the range of 0.5 to 0.45.

So for any given throttle position / power setting you could work out how much tank range was available.

 

If you want a powerful and economical diesel aero engine, look up the Napier Nomad.......