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Palomar

Member

From: USA

Registered: 2002-05-30

Posts: 9,734

Re: Ramjet & Scramjet - ...what's the difference?

http://www.aviation-history.com/engines … .htm]Click

*I asked, in another thread, the difference between a ramjet and a scramjet...basically because I've seen many articles wherein those two words seem -interchangeable-.  Not wanting to take that thread off-topic, I've posted this.

I have Googled in the past (Mark, <smile>) for an explanatory article (relative to my specific question)...I got luckier today, and found the above.  Rather straightforward. 

--Cindy 

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We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

RobertDyck

Moderator

From: Winnipeg, Canada

Registered: 2002-08-20

Posts: 7,813

Website

Re: Ramjet & Scramjet - ...what's the difference?

A ram jet uses a shaped intake to compress air and slow it down. The aircraft may travel faster than the speed of sound, but air inside the engine does not. A ram jet does not have a turbine or a compressor, it just rams air into the engine, that's why it's called a ram jet. A Supersonic Combustion RAM jet (S.C.RAM) operates with air inside the engine moving faster than the speed of sound. I could get into more technical detail, but the speed of air inside the engine is the difference.

Palomar

Member

From: USA

Registered: 2002-05-30

Posts: 9,734

Re: Ramjet & Scramjet - ...what's the difference?

http://www.aviation-history.com/engines … .htm]Click

*I asked, in another thread, the difference between a ramjet and a scramjet...basically because I've seen many articles wherein those two words seem -interchangeable-.  Not wanting to take that thread off-topic, I've posted this.

...I got luckier today, and found the above.  Rather straightforward.

*Would an aquatic ramjet be possible?  Or is there something already similar to it, used in our oceans?

If not, would that be due mostly to the density of water?  Or some other factor in the technology of it? 

Any/all answers will be appreciated and thanks in advance...

--Cindy

---

We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...

--John Sladek (The New Apocrypha)

Grypd

Member

From: Scotland, Europe

Registered: 2004-06-07

Posts: 1,879

Re: Ramjet & Scramjet - ...what's the difference?

http://www.aviation-history.com/engines … .htm]Click

*I asked, in another thread, the difference between a ramjet and a scramjet...basically because I've seen many articles wherein those two words seem -interchangeable-.  Not wanting to take that thread off-topic, I've posted this.

...I got luckier today, and found the above.  Rather straightforward.

*Would an aquatic ramjet be possible?  Or is there something already similar to it, used in our oceans?

If not, would that be due mostly to the density of water?  Or some other factor in the technology of it? 

Any/all answers will be appreciated and thanks in advance...

--Cindy

No but we can use rocket powered vehicles underwater.

They create a bubble around themselves with supercavitation and then can travel very fast. The idea of subs going at Mach 2 or higher is not far fetched there are already torpedoes in active use that do this.

Anyone for subfighters folks.

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Chan eil mi aig a bheil ùidh ann an gleidheadh an status quo; Tha mi airson cur às e.

GCNRevenger

Member

From: Earth

Registered: 2003-10-14

Posts: 6,056

Re: Ramjet & Scramjet - ...what's the difference?

http://www.aviation-history.com/engines … .htm]Click

*I asked, in another thread, the difference between a ramjet and a scramjet...basically because I've seen many articles wherein those two words seem -interchangeable-.  Not wanting to take that thread off-topic, I've posted this.

...I got luckier today, and found the above.  Rather straightforward.

*Would an aquatic ramjet be possible?  Or is there something already similar to it, used in our oceans?

If not, would that be due mostly to the density of water?  Or some other factor in the technology of it? 

Any/all answers will be appreciated and thanks in advance...

--Cindy

No but we can use rocket powered vehicles underwater.

They create a bubble around themselves with supercavitation and then can travel very fast. The idea of subs going at Mach 2 or higher is not far fetched there are already torpedoes in active use that do this.

Anyone for subfighters folks.

Ehhh that might be a stretch to talk about supersonic underwater vehicles... The only underwater machine that is fully supercavitating "cheats" by directing rocket exhaust into the bubble, which decreases the velocity it needs to make a big enough bubble. This device is the Russian "Shkval" torpedo, and has a top speed of around 250-300 knots. Speeds much higher then this underwater would be difficult to achieve with chemical fuel sources, and navigation is difficult while supercavitating. Sonar does not function either.

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[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]