- Notes, Solutions
- Liquid-Vapor Equilibrium; Clausius-Clapeyron relation from NIST Chemistry Webbook
- Cantera – implementations of Cantera in Python
- Simple Droplet model for combustion in ambient molecular oxygen (for an oxidizer)
- JANAF tables
<!– thermo.pdf on wordpress.com –>
Liquid-Vapor Equilibrium; Clausius-Clapeyron relation and Antoine Equation from NIST Chemistry Webbook
LiquidVaporEq.py, in github repository ernestyalumni:Propulsion: Web-scrape directly the National Institute of Standards and Technology (NIST) Chemistry Webbook for the Phase change data, and “clean” or format the data into the Antoine Equation and Clausius-Clapeyron relation.
Uses only the packages
You’ll be able to make plots of the Antoine Equation and Clausius-Clapeyron relation like this, in this case for methane, :
CANTERA Object-Oriented Software for Reacting Flows – This is a “Powerpoint” presentation of Cantera with lucid diagrams that makes understanding the “structure” of Cantera – just note that it’s about 10 years old and some of the syntax has changed. It also has a slide showing the author’s benchmark kinetics performance vs. Chemkin II for Constant P, H Problem with Sensitivity Analysis showing
- Chemkin II taking ~170 sec while
- Cantera taking ~40 sec(!!!)
PRF_171.cti added in
.cti Cantera file for n-heptane, along with its Chemical Kinetics (!!!)
Installing Cantera (on Mac OS X, El Capitan)
While hanging out at my alma mater, I did notice that some of my peers had difficulties installing Cantera. I’ll try to remember the steps I took for a successful install.
First, go to this page and follow its instructions. Now, I already have Xcode installed, and also digitally signed its license at the prompt. I also already installed homebrew via that ruby script.
What I had needed to do was this:
brew tap homebrew/science
brew install python icons sundials
homebrew made the installation of those above easy. I also ran this command at the command prompt of Terminal:
pip install python numpy
and it checked my python and numpy installation out (whether it needed an upgrade or not).
Then on one Mac, (2014 13” MacBook Pro, Mac OS X El Capitan), I successfully installed Cantera with brew
brew install cantera
on another Mac, (2011 MacBook Air), I successfully installed Cantera with MacPorts (i.e. port)
sudo port install cantera
and so either way should work.
My own (EY’s) Cantera Examples
LOXmeth_eq.py calculates, as a function of oxidizer/fuel O/F mass ratio, the adiabatic flame temperature, equilibrium molecular composition, mean molecular weight, ratio of specific heats, and characteristic velocity, of the combustion of oxidizer oxygen (O2) and methane (CH3). This function is further generalized (called
equil_general) to make other species be the oxidizer and fuel, such as dinitrogen tetraoxide (N2O4) and hydrazine (N2H4).
Cantera’s examples in
Let me also highlight the Python examples already in the github repository for Cantera, which is apparently in the folder Cython. Note that, as of right now, I couldn’t find these examples in my MacPorts install of Cantera.
In cython/cantera/examples are the folders
Simple Fuel Droplet model for combustion in ambient molecular oxygen (as the oxidizer), based on Chapter 10 of Turns’ An Introduction to Combustion (2011).
I was able to make these plots:
pypdfocr – Installation is nontrivial(!!!)
pip install pypdfocr
PyPDFOCR relies on the following (free) programs being installed:
- Tesseract OCR software https://code.google.com/p/tesseract-ocr/
- GhostScript http://www.ghostscript.com/
- ImageMagick http://www.imagemagick.org/
- Poppler http://poppler.freedesktop.org/ (Windows)
You do this by the following (on a Mac OS X):
brew install tesseract
brew install ghostscript
brew install poppler
brew install imagemagick
Otherwise, I received errors as the following, where I didn’t install Poppler:
/bin/sh: pdfimages: command not found
WARNING: Could not execute pdfimages to calculate DPI (try installing xpdf or poppler?), so defaulting to 300dpi
I’ll put a new blog post, here, Electromagnetism for my exploration of electromagnetism and its application to electric propulsion, as I was reviewing EM, at its deepest, theoretical, levels, in thinking about propulsion.