Balisic of the shaft

[tromic]

Here is an approximation of shaft's underwater speed and energy. The formula is based on a few measurements in swimming pool. Mono line of 120 lb was used to tie the shaft. Measurement had been done by Italian guy Luciano Garibbo.
Starting speed (v0) and mass of the shaft (m) could be changed. Function might be usable to 5 m distance.

 

[Lastonogiy]

There is a mistake in calculations.
When I put the shaft weight 560g - energy and speed increase with distance

 

[Vlanik]

There is a mistake in calculations.
When I put the shaft weight 560g - energy and speed increase with distance

 

[tromic]

There is a mistake in calculations.
When I put the shaft weight 560g - energy and speed increase with distance

Thanks! There is no mistake but the formula have restrictions. It is based on measurement for mass of the shaft form about 200 - 400 g, and for distances to about 5 m. :friday

Interesting, here is what I got. Try to upload the formula again. Maybe you accidentally changed the speed calculation.

 

[Vlanik]

For comparison
http://vlanikgun.narod.ru/Vlanik.xls

 

[tromic]

For comparison
http://vlanikgun.narod.ru/Vlanik.xls

Thanks Vladimir for this new data. My formula is not good for such a heavy shaft. It near 600 g. It would be possible to make another formula for heavy shaft but I need measurement data in water, not calculations.

 

[Vlanik]

Exsel can not mistaken...
And him without difference what weight of the harpoon if correct formula is used...
In this case work on calculation it is necessary to try back...
А for this take the worker material Luchano Garibbo.
Where possible their see?

 

[tromic]

Exsel can not mistaken...
And him without difference what weight of the harpoon if correct formula is used...
In this case work on calculation it is necessary to try back...
А for this take the worker material Luchano Garibbo.
Where possible their see?

I used data from here:
http://1578879519322306501-a-180274...RDzkVaZlIPEMWSoIfz5eu0B8IK-hdi&attredirects=0

 

[tromic]

For comparison
http://vlanikgun.narod.ru/Vlanik.xls

Vladimir, I think something is wrong with your calculation in this excel file on the link.
I compared performance on 3 m:
Vlanik 120, on 39 bar, 595 g shaft: speed - 8,6 m/s, energy - 22 J;
Cyrano 85 (vacuum barrel), on 25 bar, 300 g shaft: speed - 12,3 m/s, energy - 22 J;

I am sure Vlanik 120 must have better performance than according to your excel file! Data for Cyrano is very near to measurement results in swimming pool.

 

[Vlanik]

Counting out data derives from back edge of the harpoon...
When nose of the harpoon passes the distance 3 m, tail of the harpoon passes whole 2 m...
Consequently and evidences will others...
Their it is necessary to take from columns 2 metres...
21,92 m/sec. 45,665 dzh.
--------
I have copied exel...
Now he takes into account the long worker of the move of the harpoon...
http://vlanikgun.narod.ru/Vlanik.xls

 

[tromic]

Counting out data derives from back edge of the harpoon...
When nose of the harpoon passes the distance 3 m, tail of the harpoon passes whole 2 m...
Consequently and evidences will others...
Their it is necessary to take from columns 2 metres...
21,92 m/sec. 45,665 dzh.
--------
I have copied exel...
Now he takes into account the long worker of the move of the harpoon...
http://vlanikgun.narod.ru/Vlanik.xls

You must adjust it better. Now you have starting speed v0 = 25.8 m/s on distance 0,95 m and should be 0 m, or v0 should be more than 25.8 m/s?

 

[Vlanik]

You must adjust it better. Now you have starting speed v0 = 25.8 m/s on distance 0,95 m and should be 0 m, or v0 should be more than 25.8 m/s?

Now counting out to distances goes from tip of the harpoon...
During runaway harpoon passes the way 0,95 m...
and gains the velocity 25,8 m/sec...
So all it is correct...
I hurried and hid one necessary earl...
This cross-section of the most thick part of harpoon (мидель) shall Presently remake...
-----------------------------
Has Corrected...
Possible скачивать....

 

[tromic]

Now counting out to distances goes from tip of the harpoon...
During runaway harpoon passes the way 0,95 m...
and gains the velocity 25,8 m/sec...
So all it is correct...
I hurried and hid one necessary earl...
This cross-section of the most thick part of harpoon (мидель) shall Presently remake...
-----------------------------
Has Corrected...
Possible скачивать....

What is more important is that you make good guns and have good ideas! :friday

 

[Vlanik]

Much interesting see in this subject tests different weapon...
With result of the measurements external and internal ballistics of the harpoon...
This helped write the more exact programs a calculation for all types of the weapon...
The Many constructor of such program simply necessary...
To as far back as process конструирования, possible was pawn necessary parameters of the functioning gun