Pump Calculations Where Viscosity Changes with Distance Along Pipeline

As far as the pressure drop is concerned, it is the high viscosity end that will dominate. So what happens to the calculation if one assumes that all of the line is filled with the higher viscosity fluid and that the line is shorter, though longer than the bit currently containing the high viscosity fluid? Say 1000m of 200cp, and see what happens.

"So what happens to the calculation if one assumes that all of the line is filled with the higher viscosity fluid and that the line is shorter, though longer than the bit currently containing the high viscosity fluid? Say 1000m of 200cp, and see what happens."

Good idea - and if you know the approximate ratios between the low- and high-viscosity materials, you can more accurately choose your length: if the l-v stuff requires, say, 40% as much effort to push at the chosen speed, multiply its actual share of the pipe length by 0.40 and add to the actual high-v length. You'll probably still want to add a safety factor, but this should get you in sight of the ballpark.

Howlyy! Probably by modifying those last half way meters of pipeline by installing hi pressure--Jets Sprays Water Injectors-- in an oriented angles toward discharging downstream to help out break out such slime and heavy mix build up down the pipe, it will help keep it moving, I believe.

Probably the deal are between pumps volume capacity and operating speed too. You'll get it here with CR-4 eventually anyway I don't too wise with numbers neither but just to share a little clue here with you fellows. Allset open that valve...

Full Throtle Now,

MC

Thanks for the input and the different perspectives. I had been tinkering with the fluid properties and specifying different temperatures along the pipe line but this approach stuffed up the pressure and density calcs.

I gave the computer software a rest and after a ream of paper (well 93 pages a bit less than a 1/5^th of a ream really) and a number of pencils, I used a manual finite element type approach and calculated the losses from the pump to each pipe change, fitting and fluid property change, I have satisfied myself and the boss that we don't need a booster pump for the water and flocculent mix.

We have installed all the pumps and pipe work and the system has been running well for the last 3 days. The flow, pressure, pump speed, densities and head loss calcs were all within 2% of the measured values. The only bit that didn't fit with my calcs were the power calculations, mine suggested that the water pump would be running 20 amps below FLC but it is running at 5 amps below FLC so we needed to adjust the high amp alarms for this pump.

Thanks again for clearing the trees from my Forrest.

Henry

Excellent feedback! Thank you!

You got it. It came to you. You have the technology my friends..All good then now have fun and relax. Nice days all Buddies..!

Full Flow,

MC