The Best Cyprus Community

Skip to content


Beirut explosion .......

Feel free to talk about anything that you want.

Re: Beirut explosion .......

Postby Kikapu » Wed Aug 05, 2020 8:01 pm

Londonrake wrote:
Kikapu wrote:I wonder how many thousands of people who had survived the blast but ended with permanent hearing damage?


Current reports are saying that 300,000 have been made homeless.

Terrible. In just one swoop in few seconds. :shock:
User avatar
Kikapu
Leading Contributor
Leading Contributor
 
Posts: 15215
Joined: Sun Apr 16, 2006 6:18 pm

Re: Beirut explosion .......

Postby Cap » Wed Aug 05, 2020 8:45 pm

Cap wrote:Cyprus sends in rescue team
Choppers and dogs.


https://cyprus-mail.com/2020/08/05/repa ... 4uKzqUA8RY


Image

Image


Image
User avatar
Cap
Main Contributor
Main Contributor
 
Posts: 7205
Joined: Mon Jun 18, 2007 12:55 pm
Location: Cypriot Empire

Re: Beirut explosion .......

Postby Paphitis » Thu Aug 06, 2020 3:16 am

erolz66 wrote:
Paphitis wrote:I’m amazed you all heard it from over 200 kms away.

When you guys heard it, they explosion would have already happened 9 minutes prior.

Wasn’t it already in the news before you heard it?


The assumption that the shock wave from an explosive blast travels at the speed of sound is incorrect. They can and do travel super sonic speeds. Start with an incorrect premise and you will end up with an incorrect conclusion.


There was no assumption as I know it doesn't. Not in the first seconds, but the shock wave slows or converges towards the speed of sound. The shock wave therefore decreases velocity at a very fast rate as the Air Pressure and temperature equalizes as the wave travels away from the blast zone.

For the purposes of simplicity. the blast in Lebanon would have been heard at approximately 9 minutes after the blast. Give or take plus or minus 30 seconds. That according to my very rough calculations.

To try and explain in very simple terms, as I never intended to get in a tit for tat over physics, the initial blast shock wave would be beyond the sound barrier, but eventually slow as air temperature and pressure equalizes with the surrounding area. What radius that is anyone's guess but I would say it would definitely occur within 20kms if not much sooner. The bigger the blast, the bigger the radius where this would occur. So it depends on the severity of the blast. Imagine a massive meteor colliding with earth of a Nuclear Blast, the destruction would be more widespread as the shock wave alone with level everything out to a far greater distance.

So yeh, you can use the speed of sound and you would be within at least 10% accurate in this case. To get it to the second you would need to be able to do some advance calculations for as many radii as possible and to get it to within a second, it's probably hundreds of calculations.

My intention was not to make any statements or claim that it would be heard at exactly 9 minutes. My calculation was rough, but would be very close. I did from the top of my head. I did not use any formula but mere rules of thumb and with many assumptions such as the Distance I used which is 200kms. The actual distance is 240 kms. So it would be closer to 11 minutes.

I just asked a question out of interest because I love the science and physics behind these things. Not of course to diminish the immense suffering of the people of Lebanon. I feel very sorry for the people of Beirut. It's a terrible tragedy.

When I first saw the blast, it looked like what you wold see in Tactical Nuclear Strike. I am very glad that wasn't the case and that it was a freak accident.
User avatar
Paphitis
Leading Contributor
Leading Contributor
 
Posts: 27224
Joined: Sun May 21, 2006 2:06 pm

Re: Beirut explosion .......

Postby Paphitis » Thu Aug 06, 2020 3:38 am

Get Real! wrote:
erolz66 wrote:
Paphitis wrote:I’m amazed you all heard it from over 200 kms away.

When you guys heard it, they explosion would have already happened 9 minutes prior.

Wasn’t it already in the news before you heard it?

The assumption that the shock wave from an explosive blast travels at the speed of sound is incorrect. They can and do travel super sonic speeds. Start with an incorrect premise and you will end up with an incorrect conclusion.

More like hypersonic for detonation waves… probably Mach 10+


If it was that fast, you wouldn't be getting so many videos from people close to the actual blast.

Most of Beirut would be wiped off the face. Mach 2 or 3 is more likely. probably Mach 2.

Mach 1 at sea level is 340 m/second or 1225 km/hr. therefore, Mach 2 is 2450 km/hr at sea level in a standard atmosphere. It varies with temperature and pressure.

That's why we had whiz wheels in the old days to work our the speed of sound and determine Mach Number. All computerized today. Mach Number as a speed decreases with altitude. Which is why we are able to produce aircraft and missiles capable of exceeding speed of sound. When Chuck Yeager was the first to break the sound barrier, he did it at 60000 ft.
User avatar
Paphitis
Leading Contributor
Leading Contributor
 
Posts: 27224
Joined: Sun May 21, 2006 2:06 pm

Re: Beirut explosion .......

Postby Get Real! » Thu Aug 06, 2020 5:05 am

Paphitis wrote:
Get Real! wrote:
erolz66 wrote:
Paphitis wrote:I’m amazed you all heard it from over 200 kms away.

When you guys heard it, they explosion would have already happened 9 minutes prior.

Wasn’t it already in the news before you heard it?

The assumption that the shock wave from an explosive blast travels at the speed of sound is incorrect. They can and do travel super sonic speeds. Start with an incorrect premise and you will end up with an incorrect conclusion.

More like hypersonic for detonation waves… probably Mach 10+

If it was that fast, you wouldn't be getting so many videos from people close to the actual blast.

Most of Beirut would be wiped off the face. Mach 2 or 3 is more likely. probably Mach 2.

Mach 1 at sea level is 340 m/second or 1225 km/hr. therefore, Mach 2 is 2450 km/hr at sea level in a standard atmosphere. It varies with temperature and pressure.

That's why we had whiz wheels in the old days to work our the speed of sound and determine Mach Number. All computerized today. Mach Number as a speed decreases with altitude. Which is why we are able to produce aircraft and missiles capable of exceeding speed of sound. When Chuck Yeager was the first to break the sound barrier, he did it at 60000 ft.

Well according to the table...

hyper.png


at...

https://en.wikipedia.org/wiki/Mach_number

Hypersonic is in the range of 1,702–3,403 m/s


And if we then look at this table of explosive detonation velocities under...

https://en.wikipedia.org/wiki/Table_of_ ... velocities

we can see that the different types of explosives can attain speeds within the range of 2,700-10,000 m/s

So that would place them well in the Hypersonic, High-hypersonic, and beyond, speed ranges.
You do not have the required permissions to view the files attached to this post.
User avatar
Get Real!
Forum Addict
Forum Addict
 
Posts: 42682
Joined: Mon Feb 26, 2007 12:25 am
Location: Nicosia

Re: Beirut explosion .......

Postby Londonrake » Thu Aug 06, 2020 7:58 am

Robin Hood wrote:But you are right about the blame game. The Lebanese President says he is going to punish those responsible ........... well at least some poor bastard at the bottom end of the chain of command. Just like the Christophias investigation on the Mari incident was used to get him off the hook and blame others. The Presidents party has been in power for years, it was bought up many times about the dangers and his government did nothing about it. As you say 'MARI' all over again! :x


My recollection of the Mari enquiry was it concluded that the President was ultimately culpable. IIRC there was a recommendation the Attorney General consider charging all involved with manslaughter. Tof nevertheless dismissed the findings, denying responsibility and saying the adjudicator had exceeded his mandate.

It sounds like corruption’s rife in Lebanon, particularly in the political sphere.
Londonrake
Regular Contributor
Regular Contributor
 
Posts: 2443
Joined: Tue Dec 29, 2015 6:19 pm
Location: ROC

Re: Beirut explosion .......

Postby repulsewarrior » Fri Aug 07, 2020 1:48 am

...the Captain speaks.

http://www.abc27.com/news/us-world/inte ... explosive/

The chemicals were to be delivered to Fábrica de Explosivos de Moçambique, a company majority-owned by the Portuguese explosives company Moura Silva e Filhos.

Importing ammonium nitrate is common in Mozambique, either to make fertilizer or for use as explosives in quarries and coal pits.

The ship made a stop in Beirut to try to earn extra money by taking on several pieces of heavy machinery. But that additional cargo proved too heavy for the Rhosus and the crew refused to take it on. The Rhosus was soon impounded by the Lebanese authorities for failing to pay port fees, and never left the port again.

Prokoshev and three other crew members were forced to remain on board because of immigration restrictions. The former captain said they were stuck on the ship for 11 months, with food and other supplies running low. He said Grechushkin abandoned them without paying the wages or the debt he owed to the port.

He said the Beirut port supplied them with food out of pity.

At some point he sold some of the fuel and used the cash to hire lawyers, who got the crew released on compassionate grounds in 2014. The application to the court emphasized “the imminent danger the crew was facing given the ‘dangerous’ nature of the cargo,” the lawyers wrote in a 2015 article published by shiparrested.com, a website providing information on ship arrests and releases.

The cargo was transferred to a port warehouse only after the crew disembarked and headed back to Ukraine in 2014, Prokoshev said. It remained there ever since — until it detonated on Tuesday.
User avatar
repulsewarrior
Main Contributor
Main Contributor
 
Posts: 9671
Joined: Sat Apr 08, 2006 2:13 am
Location: homeless in Canada

Re: Beirut explosion .......

Postby Londonrake » Fri Aug 07, 2020 7:28 am

53BB33FE-D70D-47C8-826B-2C79653FF951.jpeg
You do not have the required permissions to view the files attached to this post.
Londonrake
Regular Contributor
Regular Contributor
 
Posts: 2443
Joined: Tue Dec 29, 2015 6:19 pm
Location: ROC

Re: Beirut explosion .......

Postby Londonrake » Fri Aug 07, 2020 9:59 am

Londonrake
Regular Contributor
Regular Contributor
 
Posts: 2443
Joined: Tue Dec 29, 2015 6:19 pm
Location: ROC

Re: Beirut explosion .......

Postby yialousa1971 » Fri Aug 07, 2020 4:05 pm

IS-RA-HELL did it.
User avatar
yialousa1971
Main Contributor
Main Contributor
 
Posts: 6106
Joined: Sat Aug 30, 2008 2:55 pm
Location: With my friends on the Cyprus forum

PreviousNext

Return to General Chat

Who is online

Users browsing this forum: No registered users and 0 guests