Modern computing systems are so energy- intensive to make efficient cooling vital for their operation. This is giving rise to a variety of innovative cooling solutions based on a mix of traditional and new techniques. The design and engineering of these solutions, as well as of the necessarily involved controls, requires dynamic simulation. Cooling simulation models must be capable of representing multi-physics cyber-physical systems, of connecting to specialised 3D chip simulators when high detail is needed, and at the same time of scaling up to the data centre - tailoring the detail level accordingly - when system-level studies need carrying out. In such a challenging scenario, an enabling technology is Object- Oriented Modelling (OOM). Along this approach we here present a Modelica library to serve the purposes just outlined, and that we are releasing as free software for the scientific and engineering community.Copyright (c) 2023 The Authors.