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Indian Space Capabilities

Why are there two separate scramjet projects? Isn't that sort of like duplication of efforts? Has the DRDL product been ground tested? When was the ISRO product ground tested, all I know of is the passive scramjet test back in 2010?
One is for Civilian space use while later will be used for future longrange 1500km cruise missiles.DRDLs scramjet project has been ground tested for around 7 seconds.
An interesting paper by DRDLs director about our scramjet project.
http://www.combustioninstitute-indiansection.com/pdf/SCRAMJET%20COMBUSTOR%20DEVELOPMENT.pdf
http://www.hindu.com/fline/fl3002/stories/20130208300205300.htm
 
NAND tech still hovering between 15~29 nm. There are many industries working to break 15nm barrier. So far they are facing high failure rate, inconsistent performance.
It will take another year or two to make commercially feasible and technically consistent product with <15nm tech
Yes, we are. The industry saw it coming, actually, but we had to experience the failures in terms of mechanisms and rate in order to explore the alternatives.

Just in case anyone wonders why...

What is tunnel injection? - Definition from WhatIs.com
Tunnel injection, also called Fowler-Nordheim tunnel injection, is the process by which data is written to NAND flash memory.

Fowler-Nordheim tunneling involves electrons passing through a barrier in the presence of a high electric field. During write operation on NAND flash media, the electrons tunnel through a thin dielectric material to change the electronic charge of a floating gate associated with a memory cell. A memory cell&#8217;s bit state depends upon whether or not the floating gate is charged or uncharged. When electrons are present on the floating gate, the bit state is 0. When electrons are removed from the floating gate, the bit state is 1.

The process by which data is erased from NAND flash memory is called Fowler-Nordheim tunnel releasing.
Volatile memory is the DRAM in your 'putah. If you remove power, you lose data, as in DRAM memory.

Non-volatile memory retains their data by physically moving the electrons through the barriers that make up a cell, as in the highlighted tunneling mechanism. At smaller and smaller scaling, these barriers are getting so thin that the 'pass through' count decreases to the point where the barriers are physically destroyed.

This is where we get what is called the 'write' or 'erase' limit...

SSD Performance Review - 270TB Written | StorageReview.com - Storage Reviews
...degrades as it nears its program/erase (P/E cycle) limit. For this particular drive that limit is around 5,000 P/E cycles using 32nm Toshiba MLC Toggle NAND.
You have to insert electrons to create data, then you have to remove them to erase data. Through time, eventually you will wear out the walls that separate the structures that create a memory cell. If you make those walls thinner in order to cram more cells into a finite area, inevitably you lower those P/E limits because of thinner and thinner and thinner walls. The low 10s nm scaling is giving everyone problems. Thinner walls increases operation speed and give higher capacity (gb) but decreases useful life.

This issue is in all things miniaturized at the atomic scaling level, even if there is no tunneling involved. An antenna created at this scaling may contaminate neighboring structures when it radiate. Or may not. We just have to find out.
 
Hopefully.Scramjet technology may help Brahmos-2.

It looks like they have finaly broke 20 seconds envelope.:cheers:

You know at that projected speed and altitude- a 25 second burn is approximately 50 Km covered- rough math with a margin of error of 1 km or so. You could cover 1500km in 12.5+-1 minutes. :cheesy:
 
You know at that projected speed and altitude- a 25 second burn is approximately 50 Km covered- rough math with a margin of error of 1 km or so. You could cover 1500km in 12.5+-1 minutes. :cheesy:
Sustaining 12 minutes scramjet propulsion will be challenge,but'll be worth taking.X-51A can sustain supersonic combustion inside its combustor for around5 minutes,that's 300 sec.
 
Sustaining 12 minutes scramjet propulsion will be challenge,but'll be worth taking.X-51A can sustain supersonic combustion inside its combustor for around5 minutes,that's 300 sec.

2 minutes should do the job if the weapon can be suitably sized to be viable as a standoff system- But seriously I want to see this baby even more so than the manned mission or anything else. I don't even care if its weaponised or not- I am in it for the science. Just once I want to see the cutting edge achieved.:bounce:

Obviously my calc had to take speed as a constant, since variations and their specific duration have not been mentioned.
 
2 minutes should do the job if the weapon can be suitably sized to be viable as a standoff system- But seriously I want to see this baby even more so than the manned mission or anything else. I don't even care if its weaponised or not- I am in it for the science. Just once I want to see the cutting edge achieved.:bounce:

Obviously my calc had to take speed as a constant, since variations and their specific duration have not been mentioned.
Brahmos-2 with 300KM is very much feasible if combustor can sustain around 60 sec burntime(D=By booster+scramjet).
ISROs version is a bit different though.Ramjet+scramjet both coupled in one engine=DMRJ.
 
Brahmos-2 with 300KM is very much feasible if combustor can sustain around 60 sec burntime(D=By booster+scramjet).
ISROs version is a bit different though.Ramjet+scramjet both coupled in one engine=DMRJ.

That last one is scary, any ground tests even. Was the passive scramjet component tested on the the ATV part of this amalgamated ISRO engine? What's the tentative schedule for it, if any?
 
That last one is scary, any ground tests even. Was the passive scramjet component tested on the the ATV part of this amalgamated ISRO engine? What's the tentative schedule for it, if any?
Frim what i have read from the souvneir.They'll 1st develope DMRJ then after mastering it they'll integrate DMRJ for Hypersonic test vehicile(HTV).
1)It would take-off horizontally using conventional turbo-rocket.After it has reached cruise speed of mach 1-1.2, vehicle would use DMRJ dual mode ramjet-scramjet engine to accelerate to mach 3-10.then it will land using its turborocket engine.
HTV is going be predecessor of AVATAR SSTO.
HypersonicaircraftDRDO-4.jpg

htv0.png

Development of inflight air liquification is being done in IITs and IISC.
htv1.png

htv5.png
 
@S-DUCT The US patent description of a DMRJ throws up something else- the commentary is limited to attaining high supersonic speeds and nothing more- have a look and let me know what's it about.

Patente US20090071120 - Combined cycle integrated combustor and nozzle system - Patentes do Google
Since Scramjet engines only work in around 4-5 mach numbers,It is generally developed with turbofan+ramjet engine to remove the need of Solid rocket boosters.
So basically Hypersonic space plane will have:1)Turbofan:for horizontal takeoff.Then after attaining M2 speed engine will be switched over to Ramjet and then to scamjet when adequete speed for supersonic combustion is achieved.
 
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Patannahinconfused btw AAP & BJP
I think AAP should get a chance though

What do you think ?
me too because i dont think Vijay Goel will be any better than Sheila Dixit.Besides in d past BJP has had some significant victories right??? Have they done some thing significant??Is their performance satisfactory???
 

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