The cylinderBlockMesh application is an easy Python tool which interactively creates the blockMeshDict file that discretizes a cylinder domain. Put the code in the case folder and run this by typing python3 <nameOfCode.py> in a Linux terminal. The code will start and interact with you to create the blockMeshDict file. Once the dictionary file is ready you can run the blockMesh application of OpenFOAM in order to obtain your cylinder domain. In the last version each of the boudary faces can be named. The folder system can be used to test the code. Alternatively, You can just pull the code inside the case study folder where a system folder already exists.