The gravitational water vortex turbine is an alternative to renewable energies, it transforms the hydrokinetic energy of the rivers into electric energy and it does not require a reservoir. According to studies carried out, the hydraulic efficiency can increase or decrease according to the turbine geometrical configuration. This paper presents a numerical (CFD) and analytical comparison between conical and cylindrical designs for the outlet. The results show a higher performance for conical geometry than the cylindrical tank. The fluid behavior in CFD and analytical studies presents a tangential velocity increase near to air core and outlet hole (similar behavior). The maximum theoretical power generated was 167 W and 150 W for conical and cylindrical design respectively. The differences between geometries of the outlet holes using CFD and analytical models were 11 and 7%, respectively. However, the closest results to the CFD model had different values of 31 and 29% for conical and cylindrical design, respectively. The furthest result regarding the CFD study was 55%. The principal difference is due to tank geometry, the change in discharge zone, as well as the ratio of diameter tank and outlet hole can increase or decrease the tangential velocity and make a stronger and more stable vortex formation. The theoretical power generated is a good parameter to select the height to place the rotor.

The main objetive of this study is to compare numerically the torque generated at 50, 75, 100, and 125 rpm by H-Darrieus turbine as a rotor for Gravitational Vortex Turbine. The rotational flow into the gravitational vortex turbine tank helped to decrease the negative torque in H-Darrieus rotor. The study was developed in ANSYS® CFX, where the model was configured at constant operating conditions. The highest torque was 0.117 Nm at 50 rpm, and the torque decreased with increasing rpm. The H-Darrieus works with increasing lift force, however, the rotor inside the Gravitational Vortex Turbine interacts with drag force.

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La luz de Cristo, publicado originalmente en 1936, es el segundo libro de Franz Joseph Dölger traducido al castellano, siendo el anterior una selección de sus trabajos con el título Paganos y cristianos. El debate de la Antigüedad sobre el significado de los símbolos. En esta ocasión se abordan las relaciones entre estos distintos credos a través de la luz. La obra es presentada por Pedro Sabe Andreu, quien realiza una introducción que nos aporta datos claves para poder comprender de forma correcta el texto. Del mismo modo la obra cuenta con un prólogo a cargo de Manuel González López-Corps, profesor de la Universidad eclesiástica San Dámaso de Madrid.

The generated kinetic energy of a water vortex can be transformed into electrical energy by a Gravitational Water Vortex Power Plant. Which is a new and green alternative for a conventional power plant that can induce/create a vortex without great civil construction. Previous studies focus their objective on tank design and vortex formation inside it (to study the fluid outlet velocity). However, the rotor design is a parameter that affects directly in turbine performance. The main purpose of this study is to compare numerically with the Ansys software the Savonius turbine as a Gravitational Vortex turbine rotor with the standard rotor (straight blades). The study showed that the straight-bladed rotor performed better with a generated torque of approximately 1.1 Nm, compared to 0.6 Nm generated by the Savonius. In conclusion, it was shown that the design of the rotor for the gravitational vortex turbine considerably affects its performance, where it can be increased or decreased by up to 30% difference.