Calculation of pressure drop, alternative button . Before you must select
a pipe element and fill in the fields in the window "Element of pipe" and "Flow
medium". The results you will will find in the calculation table.
Pressure drop = f
(Rate of flow)
You can calculate the pressure drop of one or more pipe elements as a
function of rate of flow (characteristic curve of pipe).
The software uses for this caclulation the actual properties of the window
"Flow medium". The properties of the table are not considered.
To calculate the characteristic curve please do so:
1.) Calculate the pressure drop of your pipe element(s) at any rate of flow.
The used ements should be matched (example: same diameter). SF Pressure Drop is
not able to check it.
The calculations of the elements are in the table now and will read out of SF
Pressure Drop to calculate the characteristic curve.
2.) You should control the correctness of the data in the window "Flow
medium". Now you can select the Menu "Pressure drop = f (Rate of flow)".
Economic
diameter of pipe
You can calculate the economic diameter of pipe at a known rate of flow. The pipe diameter of liquids will show
at small viscosity and at hight viscosity, of gases at small and hight
pressure.
This calculation is possible for circular pipes only.
Head
After you have calculated a pressure drop perhaps you need a pump to
compensate this pressure drop. For the selection of this pump you need the rate of flow and the head. Here you can calculate the minimum head of
this pump.
NPSH
In the NPHS window you can calculate the NPHS-value of plant. To calculate the NPSH you need the
following data: Pressure at suction nozzle of the pump, vapor pressure and density of
the liquid. If the vapor pressure and the density of the liquid are unknown, you
can call the database. Here you find a lot of different liquids. You can input
the temperatur and the program shows vapor pressure and density.
Attention: The data are calculated. Low differences to the reality are
possible.
Volume of
pipe/filling time
Here you can calculate the volume of the whole pipe or of a part of the pipe.
The program uses the volume flow of the first column of the calculation table,
but you can change it.
The program calculates the volume of the straight pipes and circular bends
only, other pipe elements are disregarded. The volume of corrugated pipes are an
estimation only (calculation without the rills).
Quick pump
design
Here you can design a pump quickly and easily. The software outputs the
calculated data in a Excel table.
To design do so:
1. Before you select this menu item you should input the data (volume flow,
density and viscosity) of your flow medium in the window "flow medium".
2. Select the menu item "Quick pump design".
3. Insert the vapor pressure of your flow medium. You can use the vapor
pressure database.
4. Fill out the whole form.
Additional comments:
All pressures are absolute pressures no gauge pressures.
If you have open reservoirs on the suction or discharge side please input the
ambient pressure = 1013 mbar as reservoir pressure.
If the viscosity of your flow medium is higher as water, you have to raise
the calculated power of the pump. The program doesn't it.
The pipe elements are calculated with the following resistance
coefficients: - Bends: Calculated resistance coefficient (Bend radius = 1.5 x
pipe diameter) - Cocks: Constant resistance coefficient= 0.1 - Valves:
Calculated resistance coefficient - Gate valves: Constant resistance
coefficient= 0.1 - Check valves: Calculated resistance coefficient - Check
valves swing: Calculated resistance coefficient
You can save the data of pump design as file. This function is available in
the registered version only.
Velocity to rate of flow
You can calculate at a known velocity and a known pipe diameter the
rate of flow.
This calculation is possible for circular pipes only.
Rate
of flow to velocity
You can calculate at a known rate of flow and
a known pipe diameter the velocity
of your flow medium.
This calculation is possible for circular pipes only.
Normal-m3 to
working-m3
The program needs to calculate pressure drops of gases the working volume
flow. Here you can convert the normal volume flow to the working volume
flow.
The program converts this data in working-m³ with the formula for ideal
gases. Low differences to the reality are possible.
kv value to resistance
coefficient
The program needs to calculate pressure drops of fittings the resistance coefficient. Here you can convert the kv value to resistance coefficient.
Cv value to resistance
coefficient
The program needs to calculate pressure drops of fittings the resistance coefficient. Here you can convert the Cv value to resistance coefficient.
Channel
calculations
Calculation of velocity and volume flow of a channel according
Manning-Strickler.
Channel
design
Calculation of needed cross sectional area of a channel at known volume flow and known gradient.
Discharge
calculation at a constant liquid level
Calculation of the outflowing volume and velocity out a reservoir.
Discharge
calculation at a decreasing liquid level
Calculation of the draining time out of cylindrical, globular or conical
reservoirs.
Orifice
design
Calculation of the needed orifice diameter to get a defined pressure drop in
flow medium. You can calculate orifices sharp-edged, round-edged or
thick-edged.