Physical Properties of Sea Water 1

[stanier]

I am after the physical properties of sea water at 25C. I need viscocity , density, bulk modulus and vapour pressure.
Specifically surface water <50m in Western Australia.

Do Bulk Modulus and Vapour Pressure vary very much from water?

Prefer SI units but will convert from traditional units if needed.

 

[d23]

stanier

This is a gravity chart that will answer most of your questions. On the chart it is listed as &quot;WATER, SEA&quot;

http://www.csgnetwork.com/sgvisc.html

 

[d23]

stanier

After thinking a little about your question I did a little checking.

First: the fluid chart at the first link is not very good. You should be able to do an I-net search and find a good fluid gradient chart from an oil field service company. I found one at this link:

http://www.reeves-wireline.com/publications/charts.html

In very very general terms the gradient of sea water is considered to be 1.03. The actual number is 1.02xxxx. This number is not constant. It is assumed that the salinity of water is higher at or near the equator than say near the North Pole. This is due to the evaporation rate in the warmer water as compared to the cooler water.

In general terms the info I'm offering should work, but if you need very exact numbers you should not use this.

Fluid Gradient: 1.028
Viscosity: 31.4 SSU
Sodium Chloride: 40,000 ppm
Specific Heat: 0.94

If you’re trying to calculate buoyancy for an actual structure you need numbers more accurate than the ones I'm giving you.

If you’re considering a pump a couple problems you will see is the oxygen in the water and the sea weed in the pump.

Hope this helps
David

 

[stanier]

Thanks for that. What I am really after are the parameters for waterhammer analysis with sea water as the fluid. I could do with a spreadsheet or mathcad model where the input is depth, salinity or ppm and depth. The output required if viscosity, density, vapour pressure and bulk modulus.

There must be a reference out there somewherer used by marine and offshore engineers when deisgning the rigs for waterhammer? I have been through Perry's and cant find an algorithm.

 

[d23]

stanier

I don't deal with offshore. You may want to post in the petroleum production eng forum. Pumping sea water offshore is a necessity if for nothing else than fire pumps. In fact I got the info provided from one of our in-house offshore guys.

You did ask a good question!

David

 

[simonhong]

Dear Stainer,

Would you please let me know your email addredd? My email addredd is simon@doosanheavy.com.I have some dos program. If I input temperature and salinity, the program give me the viscosity, heat capacity, etc.