This page contains source files for BSL_EARSM model for OF2.3 compressible/incompressible and OF4.1 versions and instructions to install them. The models are converted from the model created for OF1.7 by CFD-Online user elbertj. Link to the relevant post is here. cfd-online-post-link and gitlab-repo
The model is based on the implementation of Menter in CFX. The details can be found in the above referenced gitlab link.
2 OpenFOAM 2.3.1
Source code for this openfoam version can be found here. Incompressible File:Bslearsm ico2.3.1.zip and compressible File:Bslearsm2.3.1.zip To compile the library copy the source code to your foam user directory. Go inside the directory and run "wmake libso". Then add the library into your case controlDict and change RASModel to recently compiled model. There are many tutorial available for this on the internet.
3 OpenFOAM 4.1
Source code for this openfoam version can be found here. File:Bslearsm4.1.zip
For compiling this follow the instructions given in ChalmersUniversityPhDCourseLink.
When in doubt contact cfd-online user "khedar".