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Stan’s Legacy

EPG slurry

What does this mix of carrier, metal and surfactant weigh, how thick is it, does it flow smoothly at this pump rate, and what does it do to the water's permittivity?

The parts

The carrier's base water. Sets the permittivity and the temperature the viscosity is taken at. About this part.

The drive

The liquid the particulate is carried in.

The particulate.

%

The metal's share of the volume.

%

The surfactant's share of the volume.

mm

The bore the slurry is pumped through.

L/min

What the pump delivers.

From the parts

Every number handed to the simulation that you did not type, and where it came from. Each derivation that ran a calculation links to that calculation's page with these numbers in, so it can be checked alone.

  • w Water profile 2

    Well Water, as the engine's nearest named water.

  • T Temperature 15 °C

    Well Water's recorded temperature.

Result

ρ Slurry density 1.342 g/cm³

What a litre weighs.

η Slurry viscosity 1.143 mPa·s

How thick it is.

Re Reynolds number 36888

Under about 2300 it flows in layers; over about 4000, in eddies.

v Mean velocity 1.256 m/s

How fast it moves down the tube — against the holding's 50 in/s for slurry.

ε Effective permittivity 89.76

The water's dielectric constant with the metal in it.

With your numbers
36888=1.342g/cm³1.256m/s25mm1.143mPa·s
LaTeX
36888 = \frac{1.342\,\mathrm{g/cm³} \cdot 1.256\,\mathrm{m/s} \cdot 25\,\mathrm{mm}}{1.143\,\mathrm{mPa·s}}

Worth knowing

  • Flow regime in the tube — Re = 36888: turbulent. The medium is mixing as it moves, and the pressure the pump needs rises roughly with the square of the flow rather than linearly.

This result is a link — the address bar holds your numbers, so it can be pasted into a post and opened to the same answer.

The working, step by step

  1. 1. Slurry density

    ρ 1.342 g/cm³

    What the mix weighs — the volume-weighted density.

    With these numbers
    1.342g/cm³=15%0.5%998.2kg/m³+5%7.874g/cm³+0.5%1.05g/cm³
    LaTeX
    1.342\,\mathrm{g/cm³} = (1 - 5\,\mathrm{%} - 0.5\,\mathrm{%}) \cdot 998.2\,\mathrm{kg/m³} + 5\,\mathrm{%} \cdot 7.874\,\mathrm{g/cm³} + 0.5\,\mathrm{%} \cdot 1.05\,\mathrm{g/cm³}

    Open this step on its own page, with these inputs

  2. 2. Slurry viscosity

    η 1.143 mPa·s

    How much the particulate thickens the carrier.

    With these numbers
    1.143mPa·s=1.002mPa·s1+2.55%+6.25%2
    LaTeX
    1.143\,\mathrm{mPa·s} = 1.002\,\mathrm{mPa·s} \left( 1 + 2.5 \cdot 5\,\mathrm{%} + 6.2 \cdot 5\,\mathrm{%}^2 \right)

    Open this step on its own page, with these inputs

  3. With that density and viscosity through this bore at this rate: laminar or turbulent, and how fast.

    With these numbers
    36888=1.342g/cm³1.256m/s25mm1.143mPa·s,1.256m/s=40.000617m³/sπ25mm2
    LaTeX
    36888 = \frac{1.342\,\mathrm{g/cm³} \cdot 1.256\,\mathrm{m/s} \cdot 25\,\mathrm{mm}}{1.143\,\mathrm{mPa·s}}, \qquad 1.256\,\mathrm{m/s} = \frac{4 \cdot 0.000617\,\mathrm{m³/s}}{\pi \cdot 25\,\mathrm{mm}^2}
    • Re = 36888: turbulent. The medium is mixing as it moves, and the pressure the pump needs rises roughly with the square of the flow rather than linearly.

    Open this step on its own page, with these inputs

  4. What the metal does to the water's permittivity — the number the cell calculations would use instead of the water's own.

    With these numbers
    89.76=77.521+25%15%
    LaTeX
    89.76 = 77.52 \cdot \frac{1 + 2 \cdot 5\,\mathrm{%}}{1 - 5\,\mathrm{%}}

    Open this step on its own page, with these inputs

What this looks like

Reynolds number against flow rate Flow rate swept from 18.5 L/min to 55.5 L/min with everything else held at your numbers. The dashed lines cross where you are.
Reynolds number against flow rateReynolds number rises from 18444 to 55333 as flow rate rises from 18.5 L/min to 55.5 L/min. At your flow rate of 37 L/min it is 36888.10000200003000040000500006000010203040506037 L/min36888Flow rate (L/min)Reynolds number
The formula behind the curve
Re=ρvDη
Re
Reynolds number
ρ
Slurry density, kg/m³
v
Mean velocity, m/s
D
Tube diameter, m
η
Slurry viscosity, Pa·s
LaTeX
Re = \frac{ρ \cdot v \cdot D}{η}
What moves the answer Each input moved 10% either way, with the others held still, and the effect on reynolds number.
What moves the answerReynolds number is most sensitive to Tube inner diameter, which moves it by about 11.1% for a 10% change. It is least sensitive to Temperature, at about 0%.Change in the answer when each input moves by 10%-20%-10%10%20%Tube inner diameter±11.1Flow rate±10Metal loading±1.22Surfactant±0.00193Temperature±0
The formula behind the curve
Re=ρvDη
Re
Reynolds number
ρ
Slurry density, kg/m³
v
Mean velocity, m/s
D
Tube diameter, m
η
Slurry viscosity, Pa·s
LaTeX
Re = \frac{ρ \cdot v \cdot D}{η}

Open the bare numbers — the same simulation on its own page, every derived value editable.