Nancyvarkey at 10:48, 31 July 2019

2019-07-31T10:48:07Z

Kaushik Datta at 11:30, 12 July 2019

2019-07-12T11:30:43Z

Kaushik Datta at 11:20, 12 July 2019

2019-07-12T11:20:28Z

Kaushik Datta: Created page with "{| border=1 |- || '''Time''' || '''Narration''' |- || '''Slide Number 1''' '''Title Slide''' || Welcome to this tutorial on simulating a '''Custom Unit Operation '''using ''..."

2019-07-12T11:17:33Z

Created page with "{| border=1 |- || '''Time''' || '''Narration''' |- || '''Slide Number 1''' '''Title Slide''' || Welcome to this tutorial on simulating a '''Custom Unit Operation '''using ''..."

New page

{| border=1
|-
|| '''Time'''
|| '''Narration'''
|-
|| '''Slide Number 1'''
'''Title Slide'''
|| Welcome to this tutorial on simulating a '''Custom Unit Operation '''using '''Python.'''
|-
|| '''Slide Number 2'''
'''Learning Objective'''
|| In this tutorial, we will learn to:

* Create a custom unit operation using '''Python'''
* Calculate '''Overall mass '''and '''mole flow rate'''
* Calculate '''Enthalpy''' and '''outlet pressure'''
|-
||

'''Slide Number 3'''

'''System Requirements'''
|| To record this tutorial, I am using

* '''DWSIM 5. 6 update 8''' '''(Classic UI) '''and
* '''Windows 10'''

But, this process is identical in '''Linux, Mac OS X '''or '''FOSSEE OS on ARM'''.
|-
||'''Slide Number 4'''

'''Pre-requisites'''
|| To practice this tutorial, you should know to-

* Add components to a '''flowsheet'''
* Select '''thermodynamic''' packages
* Add '''material''' streams and specify their properties

|-
|| '''Slide:'''

'''Prerequisite Tutorials and Files'''

'''https://spoken-tutorial.org'''
|| The prerequisite tutorials are available on our website, '''spoken-tutorial.org.'''

You can access these tutorials and all the associated files from this site.
|-
|| '''Slide Number 5'''

'''Components:''' Methanol and Water

'''Property Package:''' Raoult’s Law
|| We will develop a '''flowsheet''' to determine the '''product stream temperature, pressure.'''

'''Molar flowrate, compositions '''and '''molar enthalpy '''from a '''mixer model''' created using '''Python.'''
|-
|| '''Slide Number 6'''

'''Inlet Stream 1:'''

Component: Pure Methanol

Temperature: 300 K

Pressure: 101325 Pa

Mass Flow: 20 kg/s

'''Inlet Stream 2:'''

Component: Pure Water

Temperature: 320 K

Pressure: 202650 Pa

Mass Flow: 10 kg/s

'''Outlet Pressure: '''Average of Inlet Stream
|| Here we give '''Inlet Stream Conditions''' and '''Pressure''' calculation parameter of the '''product stream.'''

|-
||'''Slide Number 8'''

'''Code Files'''

|| '''DWSIM-Python''' file used in the tutorial is provided as a code file on our site.

Download the files from '''Code Files''' link.
|-
||
|| I have already opened '''DWSIM''' on my machine.
|-
||
|| Please ensure that '''DWSIM''' opens as an '''administrator'''.

Please note:

If '''DWSIM''' is not opened with administrator privileges, the '''Python unit operation''' will not work.

|-
|| '''File''' >> '''Open File'''

|| Go to '''File''' menu and click on '''Open File'''.

|-
|| Point to the file on the '''Desktop'''.

Select the file from the '''Desktop'''.

||I have already downloaded and extracted the file on my '''Desktop'''.

Select the file from the '''Desktop'''.

This file already contains all the material streams necessary for this tutorial.

|-
|| Click on '''Maximize''' button.
|| Let us maximize the simulation window.
|-
|| Cursor to '''User Models''' tab
|| Now at the bottom of the main simulation window, go to '''User Models '''tab.
|-
||
|| Here we will add the '''Python script''' in the '''flowsheet'''.
|-
|| Click and drag '''Python Script''' to the flowsheet
|| Drag and drop '''Python Script''' to the '''flowsheet''' area.
|-
|| Type '''Custom Mixer'''
|| Let us change the name of this '''Unit Operation '''to '''Custom Mixer'''.
|-
|| Cursor on the interface.
|| Now, we will connect '''material streams''' to '''inlet''' and '''outlet ports''' of the '''Custom Mixer'''.
|-
|| Click '''Custom Mixer'''
|| For this click on '''Custom Mixer.'''
|-
|| Go to '''Connections'''

Click on drop down arrow against '''Inlet Stream 1'''

Select '''Methanol.'''
|| Under '''Connections,''' click on the drop-down against '''Inlet Stream 1.'''

And select '''Methanol.'''
|-
|| Click on drop down arrow against '''Inlet Stream 2'''

Select '''Water.'''
|| Next, click on the drop-down against '''Inlet Stream 2''' and select '''Water.'''
|-
|| Click on drop down arrow against '''Outlet Stream 1'''

Select '''Mixed Product.'''
|| Then, click on the drop-down against '''Outlet Stream 1''' and select '''Mixed Product.'''
|-
|| Point to all the connections.
|| All the connections are now complete.

Now we will write the code to perform the computation.
|-
|| Point to the left of the window.

Click on '''Open Python Script Editor'''
|| On the left of the window, click on '''Open Python Script Editor '''button.
|-
|| Cursor to '''Custom Mixer - Script Editor''' tab
|| '''Custom Mixer - Script Editor''' tab opens.
|-
||
|| Here we will type the '''Python script''' to perform the '''mixer''' operations.
|-
||
|| First, we will import the '''thermodynamics package''' and its related functions to the '''script'''.
|-
|| Type:

from DWSIM.Thermodynamics import *
|| Type this code in the '''script'''.

This is to import the '''Thermodynamics Packages''' and related '''functions''' to '''Python'''.
|-
||
|| Now we will extract the '''input''' from the '''feed streams.'''
|-
|| Type:

feed1=ims1

feed2=ims2
|| Type this code in the '''script'''.

'''ims1 '''and '''ims2''' are the reference to '''material streams''' that are connected in '''Inlet Stream 1''' and '''Inlet Stream 2.'''

They get recorded as '''feed1''' and '''feed2.'''
|-
|| Type:

P_1 = feed1.GetProp("pressure", "Overall", None, "", "")

P_2 = feed2.GetProp("pressure", "Overall", None, "", "")
|| Type this code in the '''script'''.

This is to read the '''pressure''' from '''inlet material streams.'''

Here, the variables '''P_1''' and '''P_2''' store the '''pressures''' of '''Methanol''' and '''Water streams'''.
|-
|| Cursor to '''GetProp''' command
|| '''GetProp''' is a '''function''' which is used to extract information from the '''inlet material stream.'''
|-
|| Point to the arguments.
|| '''GetProp function''' has 5 '''arguments'''.

These '''arguments''' have to be specified according to the information that needs to be '''extracted'''.
|-
|| Cursor to first argument '''"pressure"''' keyword
|| First '''argument''' is the '''property name'''.

This is to specify the '''property''' which has to be stored in the '''variable'''.

Here '''pressure''' is specified.
|-
|| Cursor to second argument '''"Overall"''' keyword
|| Second '''argument''' is the '''phase'''.

This is to indicate the '''phase''' for which the '''property''' specified in the first '''argument''' has to be stored.

Here '''Overall''' is specified.
|-
|| Cursor to third argument '''"None"''' keyword.
|| Third '''argument''' is the '''component ID'''.

Since we are storing the '''pressure''' of overall '''stream''' and not individual components, '''None''' is specified.
|-
|| Cursor to fourth argument'''.'''
|| The fourth '''argument''' is the '''calculation type'''.

Here we have to enter '''Pure '''or '''Mixture.'''

Since the '''property''' calculation '''type''' doesn’t apply to '''pressure''', we will leave blank here.
|-
|| Cursor to fifth argument
|| The fifth '''argument''' is the '''basis'''.

'''Mole''' or '''mass''' has to be entered here to specify the '''property''' basis.

Since the '''property''' basis doesn’t apply to '''pressure''', we will leave it blank here.
|-
|| Type:

massflow_1 = feed1.GetProp("totalFlow" ,"Overall", None, "", "mass")

massflow_2 = feed2.GetProp("totalFlow" ,"Overall", None, "", "mass")
|| Type this code in the '''script'''.

This is to read the overall '''mass flow rates''' from the '''inlet material streams'''.

variables '''massflow_1''' and '''massflow_2''' store total '''mass flow rates''' of '''Methanol''' and '''Water''' streams.
|-
|| Type:

molfrac_1 = feed1.GetProp("fraction", "Overall", None, "", "mole")molfrac_2 = feed2.GetProp("fraction", "Overall", None, "", "mole")
|| Type this code in the '''script'''.

This code will read the '''mole fractions''' of the components from the '''inlet material streams'''.

Here, we see the variables '''molefrac_1''' and '''molefrac_2. '''

They''' '''store '''mole fractions''' of the components from the '''streams''' in form of '''1-D array.'''
|-
|| Type:

molflow_1 = feed1.GetProp("totalFlow" ,"Overall", None, "", "mole")

molflow_2 = feed2.GetProp("totalFlow" ,"Overall", None, "", "mole")
|| Type this code in the '''script'''.

Here, variables '''moleflow_1''' and '''moleflow_2''' store total '''mole flow rates''' of the '''streams'''.
|-
|| Type:

enthalpy_1 = feed1.GetProp("enthalpy" ,"Overall", None, "Mixture", "mass")

enthalpy_2 = feed2.GetProp("enthalpy" ,"Overall", None, "Mixture", "mass")
|| Type this code in the '''script'''.

This is to read the specific '''enthalpy''' from the '''inlet material streams.'''

Variables '''enthalpy_1''' and '''enthalpy_2''' store the specific '''enthalpies''' of the '''streams'''.
|-
|| Cursor to fourth argument '''“Mixture”'''
|| Please note that the fourth '''argument''' is specified as a '''Mixture'''.

Here we are storing the specific '''enthalpy''' of the '''overall stream'''.

So, calculation '''type''' is specified as '''Mixture.'''
|-
|| Type:

P_3=[0]

massflow_3 = [0]

molflow_3 = [0]

enthalpy_3= [0]
|| Type this code in the '''script'''.

All the required '''properties''' for the '''outlet stream''' are initialized here.

The '''variables''' are initialized as '''vectors'''.

This makes it easy to set the values in the '''outlet stream''' using the '''SetProp function.'''
|-
||
|| Now we will code the calculation routine.
|-
||
|| First we will calculate the overall '''mass flow rate''' of the '''outlet stream'''.
|-
|| Type:

massflow_3[0] = massflow_1[0] + massflow_2[0]
|| Type this code in the '''script'''.

Total '''mass flow rate''' of the '''outlet stream''' is calculated and stored in the variable '''massflow_3.'''
|-
||
|| Now we will calculate the overall '''mole flow rate''' of '''outlet stream'''.
|-
|| Type:

molflow_3[0] = molflow_1[0] + molflow_2[0]
|| Type this code in the '''script'''.

Total '''mole flow rate''' of '''outlet stream''' is calculated and stored in the variable '''moleflow_3'''.
|-
||
|| Next we will calculate the specific '''enthalpy''' of '''outlet stream'''.
|-
|| Type:

totalenthalpy = (massflow_1[0] * enthalpy_1[0]) + (massflow_2[0] * enthalpy_2[0])

enthalpy_3[0] = totalenthalpy/massflow_3[0]
|| Type this code in the '''script'''.

Total '''enthalpy''' of the '''outlet stream''' is calculated and stored in the variable '''totalenthalpy.'''

Similarly,''' '''specific '''enthalpy''' of the '''outlet stream''' is calculated and stored in the variable '''enthalpy_3'''.
|-
||
|| Next we will calculate the individual component '''mole flow rates''' in the '''outlet stream'''.
|-
|| Type:

totalmolflow_comp1= (molfrac_1[0] * molflow_1[0]) + (molfrac_2[0] * molflow_2[0])

totalmolflow_comp2= (molfrac_1[1] * molflow_1[0]) + (molfrac_2[1] * molflow_2[0])
|| Type this code in the '''script'''.
'''Mole flow rates''' of component 1 and 2 are calculated and stored in '''totalmolflow_comp1''' and '''totalmolflow_comp2'''.
|-
||
|| Now we will calculate the '''mole fraction''' of components in the '''outlet stream'''.
|-
|| Type:

molfrac_3 = [totalmolflow_comp1 / molflow_3[0],totalmolflow_comp2 / molflow_3[0]]
|| Type this code in the '''script'''.

Component '''mole fractions''' are calculated and stored in the variable '''molfrac_3'''.
|-
||
|| Now we will calculate the '''outlet pressure.'''
|-
|| Type:

P_3[0] = (P_1[0] + P_2[0]) * 0.5
|| Type this code in the '''script'''.

'''Outlet pressure''' is calculated and stored in the variable '''P_3'''.
|-
|| Point to '''MixedProduct'''.
|| Now we will pass the calculated '''output variables''' to the '''Mixed Product material stream'''.
|-
|| Type:

out = oms1
|| Type this code in the '''script'''.

'''oms1''' is the reference to the '''material stream''' connected to the '''Outlet Stream 1.'''
|-
|| Type:

out.Clear()
|| Type this code in the '''script'''.

This is to clear any calculated values stored during previous runs.
|-
||
|| Now we will pass the calculated '''output variables''' to the '''Mixed Product material stream'''.
|-
|| Type:

out.SetProp("enthalpy", "Overall", None, "", "mass",enthalpy_3)
|| Type this code in the '''script'''.

This is to pass the calculated specific '''enthalpy''' to the '''Outlet Stream 1'''.
|-
|| Cursor to '''SetProp''' keyword
|| '''SetProp''' is a '''function''' used to assign values to the '''output stream'''.

It is a similar '''function''' to that of '''GetProp'''.

'''SetProp function''' has six '''arguments'''.

First five '''arguments''' are same as that of '''GetProp function'''.
|-
|| Cursor to '''“enthalpy_3”''' keyword
|| The sixth '''argument''' is the '''output variable'''.

This is to specify the '''vector variable''' that we want to assign to that particular '''property'''.

We want to assign the '''vector enthalpy_3''' to '''enthalpy''' of the '''Outlet Stream 1'''.
|-
||
|| Similarly we will pass the remaining calculated '''variables''' to the '''Outlet Stream 1'''.
|-
|| Type:

out.SetProp("pressure", "Overall", None, "", "", P_3)

out.SetProp("fraction", "Overall", None, "", "mole", molfrac_3)

out.SetProp("totalFlow", "Overall", None, "", "mass", massflow_3)
|| Type this code in the '''script'''.

This is to pass the calculated '''pressure, component mole fractions''' and '''total mass flowrate''' to the '''Outlet Stream 1'''.
|-
|| Type:

out.PropertyPackage.DW_CalcEquilibrium(PropertyPackages.FlashSpec.P, PropertyPackages.FlashSpec.H)
|| Type this code in the '''script'''.

This is to set the flash calculation method for the '''Outlet Stream 1'''.
|-
|| Cursor on '''out.PropertyPackage.DW_CalcEquilibrium '''keyword
|| '''out.PropertyPackage.DW_CalcEquilibrium''' is a '''function''' used to set the method of '''flash''' calculation used.

The default '''flash '''calculation method is done with the '''Temperature and Pressure (TP Flash)'''.

Here we do not know the '''outlet temperature'''.

So, we set the '''flash type''' to '''Pressure and Enthalpy Flash (PH Flash).'''
|-
|| Cursor on '''PropertyPackages.FlashSpec.P, PropertyPackages.FlashSpec.H''' keyword
|| The '''variable''' at the end of the '''PropertyPackages.FlashSpec''' signifies which '''variable''' is used for '''flash''' calculation.

Here in the first '''argument,''' we pass the '''Pressure''' and in the next we pass the '''Enthalpy.'''
|-
||
|| With this, the '''Python script''' is completed.
|-
||
|| Now we will run the '''simulation.'''
|-
|| Click '''Solve Flowsheet'''
|| So, from the toolbar, click on '''Solve Flowsheet''' button.

|-
|| Point to '''Flowsheet''' tab.
||Switch to '''Flowsheet''' tab.
|-
|| Click '''Mixed Product'''
|| When the calculations are completed, click on the '''Mixed Product '''in the '''flowsheet'''.
|-
|| Point to '''Property Editor Window'''

Hover mouse at '''Input Data'''
|| Under '''Stream Conditions, '''check '''Temperature''', '''Pressure''' and '''Molar Flow'''.
|-
||
|| Let's summarize.
|-
|| '''Slide Number 7'''

'''Summary'''
|| In this tutorial, we have learnt to

* Create a custom unit operation using '''Python'''
* Calculate '''Overall mass '''and '''mole flow rate'''
* Calculate '''Enthalpy''' and '''outlet pressure'''

|-
|| '''Slide Number 8'''

'''Assignment'''

'''Compounds: '''

Methanol (CH<sub>3</sub>OH)

Water (H<sub>2</sub>O)

'''Property Package: '''Raoult’s Law'''

'''Inlet stream:'''

Mass Flow: 1000 kg/h

Temperature: 50 degree C

Pressure: 1 bar

'''Separation Pressure''': 0.075 bar
|| As an assignment,

Create a custom model for a flash column to separate the gas-liquid phase for a mixture of compounds.

Calculate the amount of liquid and vapour generated at 0.075 bar.

Compare the results with in-built Gas-Liquid Separator available.
|-
|| '''Slide Number 9'''

'''About the Spoken Tutorial Project'''
|| Watch the video available at the following link.

https://spoken-tutorial.org/

It summarizes the Spoken Tutorial project.
|-
|| '''Slide Number 10Spoken Tutorial Workshops'''
|| The Spoken Tutorial Project Team

* Conducts workshops and
* Gives certificates.
* For more details, please write to us.

|-
|| '''Slide Number 11'''

'''Forum Slide'''

Do you have questions in this '''Spoken Tutorial?'''

Please visit this site

Choose the minute and second where you have the question.

Explain your question briefly.

Someone from the FOSSEE team will answer them.
|| Please post your times queries in this forum.
|-
|| '''Slide Number 12'''

'''DWSIM Flowsheeting Project'''
|| The '''FOSSEE''' team coordinates conversion of existing flow sheets into '''DWSIM.'''

We give honorarium and certificates.

For more details, please visit this site.
|-
|| '''Slide Number 13'''

'''TextBook Companion Project'''
|| The '''FOSSEE''' team coordinates coding of solved examples of popular books.

We give honorarium and certificates.

For more details, please visit this site.
|-
|| '''Slide Number 14'''

'''Lab Migration Project'''
|| The '''FOSSEE''' team helps migrate commercial simulator labs to '''DWSIM.'''

We give honorarium and certificates.

For more details, please visit this site.
|-
|| '''Slide Number 15'''

'''Acknowledgements'''
|| '''Spoken Tutorial''' and '''FOSSEE''' projects are funded by '''NMEICT, MHRD''', Government of India.
|-
|| '''Slide Number 16'''

'''Thanks'''
|| This tutorial is contributed by Kaushik Datta and Priyam Nayak.

Thanks for joining.
|-
|}

@@ Line 43: / Line 43: @@
 '''https://spoken-tutorial.org'''
-|| The prerequisite tutorials are available on our website, '''spoken-tutorial.org.'''
+|| The prerequisite tutorials are available on our website.
-−
 You can access these tutorials and all the associated files from this site.
@@ Line 105: / Line 104: @@
 Please note:
-If '''DWSIM''' is not opened with administrator privileges, the '''Python unit operation''' will not work.
+If '''DWSIM''' is not opened with '''administrator privileges''', the '''Python unit operation''' will not work.
 |-
@@ Line 398: / Line 397: @@
 totalmolflow_comp2= (molfrac_1[1] * molflow_1[0]) + (molfrac_2[1] * molflow_2[0])
 || Type this code in the '''script'''.
-'''Mole flow rates''' of component 1 and 2 are calculated and stored in '''totalmolflow_comp1''' and '''totalmolflow_comp2'''.
+'''Mole flow rates''' of component 1 and component 2 are calculated and stored in '''totalmolflow_comp1''' and '''totalmolflow_comp2'''.
 |-
 ||

@@ Line 527: / Line 527: @@
 || Let's summarize.
 |-
-|| '''Slide Number 7'''
+|| '''Slide Number 9'''
@@ Line 538: / Line 538: @@
 |-
-|| '''Slide Number 8'''
+|| '''Slide Number 10'''
@@ Line 581: / Line 581: @@
 Compare the results with in-built Gas-Liquid Separator available.
 |-
-|| '''Slide Number 9'''
+|| '''Slide Number 11'''
 '''About the Spoken Tutorial Project'''
@@ Line 590: / Line 590: @@
 It summarizes the Spoken Tutorial project.
 |-
-|| '''Slide Number 10Spoken Tutorial Workshops'''
+|| '''Slide Number 12'''
 || The Spoken Tutorial Project Team
@@ Line 598: / Line 599: @@
 |-
-|| '''Slide Number 11'''
+|| '''Slide Number 13'''
 '''Forum Slide'''
@@ Line 613: / Line 614: @@
 || Please post your times queries in this forum.
 |-
-|| '''Slide Number 12'''
+|| '''Slide Number 14'''
 '''DWSIM Flowsheeting Project'''
@@ Line 622: / Line 623: @@
 For more details, please visit this site.
 |-
-|| '''Slide Number 13'''
+|| '''Slide Number 15'''
 '''TextBook Companion Project'''
@@ Line 631: / Line 632: @@
 For more details, please visit this site.
 |-
-|| '''Slide Number 14'''
+|| '''Slide Number 16'''
 '''Lab Migration Project'''
@@ Line 640: / Line 641: @@
 For more details, please visit this site.
 |-
-|| '''Slide Number 15'''
+|| '''Slide Number 17'''
 '''Acknowledgements'''
 || '''Spoken Tutorial''' and '''FOSSEE''' projects are funded by '''NMEICT, MHRD''', Government of India.
 |-
-|| '''Slide Number 16'''
+|| '''Slide Number 18'''
 '''Thanks'''

@@ Line 38: / Line 38: @@
 |-
-|| '''Slide:'''
+|| '''Slide Number 5'''
 '''Prerequisite Tutorials and Files'''
@@ Line 48: / Line 48: @@
 You can access these tutorials and all the associated files from this site.
 |-
-|| '''Slide Number 5'''
+|| '''Slide Number 6'''
 '''Components:''' Methanol and Water
@@ Line 58: / Line 58: @@
 '''Molar flowrate, compositions '''and '''molar enthalpy '''from a '''mixer model''' created using '''Python.'''
 |-
-|| '''Slide Number 6'''
+|| '''Slide Number 7'''

DWSIM/C3/Custom-Unit-Operation-using-Python/English - Revision history

Nancyvarkey at 10:48, 31 July 2019

Kaushik Datta at 11:30, 12 July 2019

Kaushik Datta at 11:20, 12 July 2019

Kaushik Datta: Created page with "{| border=1 |- || '''Time''' || '''Narration''' |- || '''Slide Number 1''' '''Title Slide''' || Welcome to this tutorial on simulating a '''Custom Unit Operation '''using ''..."