HYCOOL-IT: D4.1 Numerical model of the rack-integrated adsorption chiller and design of the proof-of-concept

The present report focuses on the development of a numerical simulation model of the innovative adsorption chiller technology, proposed within the HYCOOL-IT project, for the integration into server racks and the first design of the prototype to be manufactured in the framework of WP4. The developed model is implemented in Modelica language through the commercial distribution Dymola. It allows the detailed simulation of the main adsorption chiller components such as adsorber, evaporator/condenser, controller and hydraulic circuit. Due to the lack of data, the air-to-water heat exchanger used to provide cold air for the server cooling was simulated using an external software to retrieve the operating data. The implemented model, using the reference components’ features provided by SORGE, was used to perform a multiparametric analysis of the operation under variable boundary conditions, aiming at mainly analysing their impact on the achievable cooling power and the relative sizing of the components. Based on the outcomes of the simulation, a first complete design of the first PoC was completed. The main criterium was to keep a design able to fit inside the rack, substituting the rear door. Accordingly, the components size and their mechanical integration were designed in a slim and high configuration. At the bottom, the hydraulic group is integrated distributing the refrigerant to the two adsorbers, located in the middle of the prototype. Finally, the air-to-water heat exchanger is connected at the top and is cooled down directly by the refrigerant coming out from the evaporation loop of the adsorption chiller. The designed PoC will be manufactured in order to be experimentally validated under lab-controlled conditions. The results will be used to refine the adsorption chiller design as well as to validate the developed numerical mode, which will be further exploited to optimize the prototype control and to define the first version of the specific SIMBot.