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From: Jerry DeLisle on 6 Jun 2010 13:28
On 06/05/2010 07:56 PM, Uno wrote:
> On 6/5/2010 10:26 AM, Ron Shepard wrote:
>> In article<86ulj7Ff3dU1(a)mid.individual.net>, Uno<merrilljensen(a)q.com>
>
>> You cannot know. If the pressure within the pipe is greater than the
>> pressure at 32.8 ft, then the liquid will continue to flow, but at a
>> slower rate. If the pressure within the pipe is less than the pressure
>> at 32.8 ft, then it will flow in the opposite direction.
>>
>> So you need an additional important piece of information to answer the
>> question.
>
> Right.
>
> Let's say the pressure is typical city water pressure. This isn't too
> hard for anyone to measure.
>
> E:\gcc_eq32>gfortran -Wall -Wextra p1.f90 -o out.exe
>
> E:\gcc_eq32>out
> atmos is 160.93440
> city_pressure is 65.000000
> atmos2 is 4.5699549
> depth is 149.93291
>
> E:\gcc_eq32>type p1.f90
> implicit none
>
> real :: feet_per_mile, feet_per_atmos, atmos
> real :: city_pressure, atmos_per_pound, atmos2
> real :: depth
>
> ! values
> feet_per_mile = 5280
> feet_per_atmos = 32.808399169
> city_pressure = 65 !typical water pressure in lb/in^2
> ! http://en.wikipedia.org/wiki/Atmosphere_(unit)
> atmos_per_pound = 70.307E-3
>
> ! calculations
> atmos = feet_per_mile / feet_per_atmos
> atmos2 = city_pressure * atmos_per_pound
> depth = feet_per_atmos*atmos2
>
> !output
> print *, "atmos is ", atmos
> print *, "city_pressure is ", city_pressure
> print *, "atmos2 is ", atmos2
> print *, "depth is ", depth
> endprogram
> ! gfortran -Wall -Wextra p1.f90 -o out.exe
>
> E:\gcc_eq32>
>
> So, if instead of opening a water spigot at seal level, you went 150
> feet down, would it have no net flux?a b
>
>>
>>> q2) How would this vary if salt were added in the amounts of the gulf
>>> of mexico?
>>
>> You need to look up the density of sea water and compare that to fresh
>> water. You can then determine the feet per atmosphere of pressure for
>> sea water, and that should give you enough info to answer the question.
>
> Ok.
>
> Gotta run
Water pressure due to gravity is about 27.68 inches / psi. (Seawater is a bit
more dense then pure water) So, 150 feet down, the pressure will be about
150*12/27.68 psi. (about 65 psi, and a bit more for seawater)

Jerry
From: Uno on 8 Jun 2010 01:44
Jerry DeLisle wrote:

> Water pressure due to gravity is about 27.68 inches / psi. (Seawater is
> a bit more dense then pure water) So, 150 feet down, the pressure will
> be about 150*12/27.68 psi. (about 65 psi, and a bit more for seawater)

Alright, thx Jerry. I've got this gussied up a little better now:

$ pwd
/home/dan/source/fortran_stuff
$ gfortran -Wall -Wextra p2.f90 -o out.exe
$ ./out.exe
The hydrostatic pressure at the wellhead is 152.39999
city_pressure is 65.000000
atmos2 is 4.5699549
depth is 149.93291
$ cat p2.f90
implicit none

real :: wellhead_depth, feet_per_atmos, atmos
real :: city_pressure, atmos_per_psi, atmos2
real :: depth

! values
wellhead_depth = 5000
! source: http://en.wikipedia.org/wiki/Deepwater_Horizon_oil_spill
feet_per_atmos = 32.808399169
city_pressure = 65
! typical water pressure in lb/in^2, aka, psi
atmos_per_psi = 70.307E-3
! source: http://en.wikipedia.org/wiki/Atmosphere_(unit)

! calculations
atmos = wellhead_depth / feet_per_atmos
! units: ft / (ft/atm) = atm
atmos2 = city_pressure * atmos_per_psi
! units: psi * (atm/psi) = atm
depth = feet_per_atmos*atmos2
! units: (ft/atm) * atm = ft

!output
print *, "The hydrostatic pressure at the wellhead is ", atmos
print *, "city_pressure is ", city_pressure
print *, "atmos2 is ", atmos2
print *, "depth is ", depth
endprogram
! gfortran -Wall -Wextra p2.f90 -o out.exe
$

This gives me something to bring to a conversation when I go talk to
someone who spent his life in magnetohydrodynamics. I'll use a hard
copy of this program as a manipulative when I go down to UNM. Fortran
is everywhere there.

Oh, and Jerry, you wrote this regarding a minor breakage:

> My apologies for the breakage.

As a gfortran user, I feel like you *never* need to apologize to me.
But maybe you do so for your own ends. Let me also apologize for not
sending you the money that gfortran is worth to me.

Anyways, if anyone has any notions of how fortran informs an oil leak at
a 152.4 atmospheres, I am--like our President--all ears.

Cheers,
--
Uno
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