| 1. |
Compute the Reynolds Number:
|
Nre=6.31w
|
= |
3,161 Qspgr
|
|
µD
|
µD
|
Nre = Reynolds number dimensionless
D = Inside diameter of mixer housing, inches
Q = Volumetric flow rate, gallons/minute
? w = Mass flow rate, pounds/hour
spgr =Specific gravity
µ =Absolute viscosity, centipoise
|
| 2. |
If Nre < 500 the flow is laminar. Use either Fig.1 for LPD or Fig.3 for ISG mixers to estimate the pressure drop per element. If Nre > 500 the flow is turbulent. The pressure drop per element is estimated from Fig.2 for LPD or Fig.4 for ISG mixers.
|
| 3. |
Multipy the pressure drop per element by the number of elements to obtain the estimated pressure drop through the mixer.
|
| 4. |
The estimated pressure drop must be corrected for physical properties as follows:
- For turbulent flow, multiply the estimated pressure drop by the specific gravity and the correction factor K from table 2to obtain the actual pressure drop.
- For laminar flow, the pressure drop is proportional to the viscosity. Since Figs.1 and 3 are based on a fluid having a viscosity of 10,000 cps, the actual pressure drop is calculated as follows:
Actual Pressure Drop = (fluid visc.cps) x est. pressure drop 10,000
|
| 5. |
To determine LLPD pressure drop multiply LPD pressure drop by 0.46 (if turbulent). In laminar flow the LPD and LLPD have similar pressure drop.
|
| 6. |
If actual pressure drop exceeds the allowable value, repeat above steps using a larger mixer diameter.
|
