The work presents a heat transfer analysis carried out with the use of COMSOL Multiphysics software applied to a new solar concentrator, defined as the Compound Parabolic Concentrator (CPC) system. The experimental measures have been conducted for a truncated CPC prototype system with a half-acceptance angle of 60°, parabola coefficient of 4 m−1 and four solar cells in both covered and uncovered configurations. These data are used to validate the numerical scenario, to be able to use the simulations for different future systems and works. The second challenge has been to change the reflector geometry, the half-acceptance angle (60° ÷ 75°) and the parabola coefficient (3 m−1 ÷ 6 m−1) to enhance the concentration of sun rays on the solar cells. The results show that the discrepancy between experimental data and COMSOL Multiphysics (CM) have led to validate the scenarios considering the average temperature on the solar cells. These scenarios are used for the parametric analysis, observing that the optimal geometry for the higher power and efficiency of the whole system is reached with a lower half-acceptance angle and parabola coefficient.

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This work focuses on the feasibility study of a new suction hood model that allows the complete disposal of the fumes produced during cooking. The originality of this study lies in the conception of a new functional geometry meant to reduce consumption, focusing on the increase of both efficiency and aspiration efficiency. The new technology is based on the Coandă effect applied on two innovative air capture systems of hood model. On one hand the air flow amplifier, a system that, starting from a low inlet flow rate, allows 10 times increasing of the output flow rate. On the other hand, the bladeless fan, which is usually implemented in newest bladeless ventilation systems. A simulation campaign has been conducted with COMSOL Multiphysics software to validate the simulation scenarios comparing the experimental results with respective references. For the post-validation step, the parametric sweep function has been used to study the system behaviours to every change of velocity, flow rate and extension of the ejector. The obtained results show the feasibility of these new suction systems, which present lower consumptions than other modern ventilation systems for kitchens. The computed results show that the perimeter velocity is in accordance with European standards. The perimeter velocity for air flow amplifier geometry allows a suction capacity range between 460 m 3 /h and 3600 m 3 /h. In the bladeless fan case, the suction capacity is in a range between 325 m 3 /h and 2500 m 3 /h. Therefore, the two geometries can be installed for both domestic and commercial kitchens.