The biggest future challenge for astronomers, cosmologists and particle physicists is to determine the nature of the two main components of our universe: dark matter and dark energy. With this goal in mind and fortified by the new results of the Planck satellite, European, American, and Japanese Institutes, space agencies, and governments have invested in new missions that are about to see their first light (e.g. e-ROSITA, DES, EUCLID, CCCAT, SPT-3G, ACT-POL, ASTRO-H). All of them propose galaxy clusters as cosmological probe and/or astrophysical laboratory. The multi-chromatic image collection of these systems will allow determining with unprecedented precision the key cosmological quantity: the cluster mass.Our project, built on previous experience of the Researcher and on the multi-wavelength expertise of the scientists of the Observatory of Trieste, aims at clarifying any possible bias in the mass determination and at offering a powerful procedural strategy to select the optimal sample for cosmological studies. In the specific, by means of large sets of simulations, we propose1. To characterize in-homogeneity in temperature, pressure, and density maps and their connection with X-ray and millimetric measures.2. To test triaxility reconstruction techniques of the cluster potential by combining X-ray, millimetric, and optical (via gravitational lensing and galaxy dynamics) observations.The philosophy of our team goes well beyond the standard analysis limited to the numerical models aiming at providing the observers with conclusive models and best strategies for observational campaigns. For this goal, our simulated clusters will be processed through X-ray and optical simulators to generate synthetic images that will be analyzed in an observational-like fashion. In vision of future surveys, the large catalogues that we will produce and share with the community are the most suitable tools to characterize the interconnection between multi-band observations.