If the requirement is crystal clear to the product owner and the application tobe developed will last for more than a year or so, which of the SDLC modelshould be considered to develop the software?

There are various SDLC models available that could be implemented for
development of any software depending upon various parameters. In our case,  as the project is long term and requirement is crystal clear and well  documented, so chances of introducing and changes in the later stage of  development is negligible. Under such scenario, waterfall model can be used to  develop this software.