The height at which Jet planes fly Oxygen must be very rare , so how much Oxygen is required for combustion ?
At high altitudes the Oxygen level must be very low, still combustion is taking place , how is that possible on such a low Oxygen level ?
Oxygen does not get rare as you go up, it is about the same % of the air composition as at sea level. What happens, however, is that the pressure and the density go down as you go up. At the altitude a jetliner cruise (35000 ft or so), the density of the air is about 30% of what exists at sea level, but (and that is the neat part) this density is also a factor in the lift, which also depends on how much air one encounters to provide the pressure differential required to fly.
The solution? Fly faster. If you go faster, you encounter more air, and thus more oxygen, per unit time. This is actually the reason why airliner fly high: so they can fly faster.
Flying faster means you get enough air per unit of time to sustain combustion at a rate that is compatible with the thrust required to keep flying at that speed. Remember that any jet engine is made of 3 parts: a compressor at the front (that compresses air to actually a much higher pressure then what we have a sea level), a combustion chamber, and a turbine that extract some of the power from the hot gases to drive the compressor and accesories; the rest of the energy is propulsive power (I simplify; high bypass turbofan have most of their thrust coming from the by-pass air that only went through the low pressure compressor stage).
As you get further up, the requirement to fly faster still to get enough oxygen goes to above the speed of sound and eventually much higher; at such altitude an aircraft has to fly so fast and use so much energy, most engines run out of power (and you start having other problems, like kinetic heatic of the airframe). All those, and the fact that compression of the air around the speed of sound creates shock wave that take energy away, that wings may not be designed for, and so on; those considerations establish the ceiling of an airplane, the maximum altitude at which it can fly.
Just remember one thing: if you have less oxygen, say only 1/3 the amount, and you do no benefit from the high speed factor, you can still burn 1/3 as much fuel. That is what airplane do as well. Sure the thrust goes down, but as long as it is enough to balance drag, there is no need to accelerate or have excess power to climb, as the airplane is already at its peak altitude and speed.
Very rare fight kung fu vs taekwondo (Master Ehsan Shafiq)
|
|
10 Neodymium Magnets 1/2 x 1/8 inch Disc N48 $3.99 ONE lot of 10 Magnets. Size: 1/2 inch diameter x 1/2 inch thick discs. Nickel (Ni) Plated (silver-like shine) Grade: N48 – Extremely powerful magnetic material Pull Force is approximately 6.1 pounds under ideal conditions. These discs are axially magnetized, so the strong North/South poles are in the center of the flat sides. That makes them easier to stack into a cylinder than to connect side by … |
|
|
Three By Three Seattle Tiny Mighties Magnets, 0.125 Inches Diameter, Chrome, 16 Pack (20500) $9.95 At 1/8 inch in diameter these chromed Tiny Mighties are surprisingly strong for their size, yet so small they’re almost invisible. These ultra strong magnets are commonly referred to as neodymium magnets or rare earth magnets. One Tiny Mighty is strong enough to hold 3 sheets of 8 1/2 x 11 paper. This set includes 16 magnets, from Three By Three Seattle…. |
|
|
Libbey Polaris Drinking Glasses and Tumblers, Set of 16 $26.99 16-piece set of drinking glasses with heavy, 1-inch-thick rounded bases that impart substance and stabilityWith 16 glasses total, the set includes eight tumblers and eight glassesThe glasses measure 2-3/4 by 2-3/4 by 6-1/2 inches and hold 16-1/4 ounces; tumblers are 3 by 3 by 4 inches and hold 12-1/4 ouncesLayers beautifully with a variety of dinnerware and table settings; crystal-clear glass cons… |
|
|
The Beach Boys – Limited Edition 50th Anniversary Collection ‘ZinePak $21.29 This commemorative 50th Anniversary Beach Boys release includes an 11-song CD, a collectible 72-page magazine and three exclusive postcards. The CD features an all-new recording of the hit “Do It Again” available exclusively on this release, plus 10 more of the band’s greatest hits. The magazine includes dozens of rare photographs from the band’s career and exclusive new interviews with Brian Wils… |
|
|
Audioslave $6.06 The debut of thundering supergroup Audioslave–featuring members of Rage Against the Machine post-Zack de la Rocha with ex-Soundgarden singer Chris Cornell–is as much curio as fascinating blend of visions. Cornell might be outnumbered, but his unmistakable holler and nihilistic imagery ensure that Audioslave, the album, recalls early Soundgarden. That’s especially true since de la Rocha took Rage… |
|
|
The Best of Rare Earth – 20th Century Masters $2.61 … |
|
|
Disney’s Sing Along Songs – Beach Party at Walt Disney World [VHS] $9.99 Sing, dance, and play along with Mickey and the gang in fun-filled musical adventures! It’s easy as you read the on-screen lyrics to favorite kid songs! In BEACH PARTY AT WALT DISNEY WORLD, Mickey, Minnie, Donald, Goofy, Tigger, and The Sing-Along Kids hit the waves and have a ball at Blizzard Beach, Typhoon Lagoon, Shark Reef, and more. What a cool place to have oceans of fun!… |
|
|
WWF Royal Rumble 1989 [VHS] $39.99 … |
|
|
The Deadliest Art – The Best of the Martial Arts Films [VHS] $9.98 … |
|
|
Magcraft NSN0573 3/8-Inch by 1/8-Inch Rare Earth Disc Magnets, 30-Count $9.99 Rare earth magnets are the strongest type of permanent magnet currently made. They are amazingly powerful for their size and have innumerable uses. These disc magnets are 0.375 inch (9.5mm) diameter and 0.125 inch (3.2mm) thick. They are magnetized through the thickness. They are composed of grade 40 neodymium iron boron magnetic material and are plated in nickel-copper-nickel for a shiny corrosio… |
Tags: art, blog, history, photography, rare very expensive, rare very old books, rare very rare, rare very rare dog breeds, rare very rare drop runescape, very