Joan I. Rosell's research while affiliated with Universitat de Lleida and other places

... Advanced materials are also making their way into industrial applications. Thus, Desideri et al. [26] and Wang et al. [27] presented numerical and experimental studies in which a selfadaptive memory alloy was used, which can change the flow conditions in the observed channels when necessary and in this way increase the turbulence of the flow and thus also intensify the heat transfer. With the proper application of such systems, in some cases up to 70% of pump energy can be saved, or heat transfer can be improved by 50 to 80%. ...

... The researchers are continuously investigating other ways to overcome obstacles to controlling overheating and preventing electrical fire in electrical devices by using autonomous actuators based on smart materials [10]. The viability of the suggested smart system idea examines how advanced smart composite materials can be implemented in commercial activities, with a focus on potential alarm applications. ...

... For MJ solar cells such as triple-junction type (GaInP/GaAs/Ge), the temperature of the cell raises to the value of 1300°C under no cooling condition under 1000 suns (Abo-Zahhad et al., 2020;Cotal et al., 2009). Laguna et al. (2018) assessed the temperature non-uniformity and electrical performance for a CPV dense array of 6 × 8 cells under different concentrated illumination profiles. The authors found that power losses increase linearly with non-uniformities on illumination and temperature. ...

... The authors found that power losses increase linearly with non-uniformities on illumination and temperature. Fernández et al. (2018) reported the impact of the reduction of average cell temperature and non-uniformity degree on the performance reduction of a densely packed module of concentrating PV. The authors achieved an improvement up to 3.38% on net PV power with low pumping power requirements. ...

... Barrau et al. [3][4][5] and Rubio Jimenez et al. [6] proposed different ways of reaching more uniform temperatures of heated zones by using a hybrid jet impingement/micro-channel cooling device and a micro-pin fin heat sink with variable fin density. Along this line, a cooling scheme consisting of an array of microfluidic cells with adaptive valves capable of maintaining a surface temperature below a critical point by locally modulating flow rate in response to changes in heat load, was investigated by [7][8][9]. ...

... Compared with the conventional regular-sized channel heat sinks, microchannel heat sinks have been more widely used in the cooling, heat exchange, and thermal control modules of automation devices [7][8][9][10][11][12] due to their many merits such as high efficiency of heat exchange, energy-saving, and can make full use of the sensible and latent heat. Compared with air-cooled heat exchangers whose heat dissipation performance is greatly limited by the thermal and physical properties of the air, microchannel heat sinks have better heat transfer and isothermal performance [13][14][15][16][17][18][19][20][21][22][23][24]. To achieve higher efficiency of heat dissipation, the design of heat dissipation enhancement of automation systems from an overall optimization scale based on microchannel units has received more attention in both academic circle and the industry, and it is of great research value to explore the laws of enhanced heat dissipation in the microchannel units of automation systems. ...

... Beberapa penelitian pendahuluan tentang kolektor PV/T dengan air sebagai fluida sudah dilakukan oleh Amrizal dkk. Penelitian ini mengembangkan metode pengujian dengan penggunaan metode aliran fluida piston dan filtering data [3][4]. Hasil penelitian menunjukkan adanya kesesuaian model dengan hasil eksperimen. ...

... The principle drawback of these systems is that solar tracking is achieved by movement of the whole system, incurring the aforementioned restrictions with regard to architectural integration. The University of Lleida is currently developing concentration technology which uses reflection, in a similar way to the systems developed by (Chemisana and Rosell, 2009), but with a design which prioritizes architectural integrability. The system consists of a linear Fresnel reflector which focuses radiation in a manner analogous to a lens. ...

... Integrating PCM with solar collectors can not only reduce the highest temperature of the solar collectors, thereby extending the lifetime [17] and increasing the system thermal efficiency [18], but also fulfil on-site thermal storage [19]. For instance, a paraffin with a phase change temperature of around 60°C was enhanced using nano-Cu additives and laminated in a flat plate solar collector by Al-Kayiem and Lin [20] for water heating application. ...

... Although not as common as flat-plate BIPV/T systems, there are some studies in academic literature where concentrated systems were integrated into buildings. In a study, Chemisana et al. [100] presented a concentrated BIPV/T-liquid system. The developed PV/T module contained a transparent cover (glass) a longitudinal PV module, absorber surface, fins and fluid tube made from copper and aluminium casing. ...