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Rainfall simulators are versatile research tools that facilitate studying rain events and the many related physical phenomena. This work describes the development and validation of an indoor, large-scale rainfall simulator comprising a rain module installed 10.4 m from ground level, a redistribution screen at an adjustable distance below the rain module, and an ultra-filtered-water recirculation system. The droplet formers installed in the rain module were selected to achieve a wide range of rain intensities. The simulator was calibrated and validated using local natural rainfall data collected with a disdrometer over 30 months. The height of the rain module allows terminal velocity to be reached at ground level. At the same time, the redistribution screen and the droplet formers guarantee the wide variability of simulated rainfall in terms of intensity and the size of the drops. As a result, we show that the rain simulator, with proper calibration of the screen’s position, can reproduce measured natural rainfall over a broad range of intensities with high spatial and temporal uniformity and kinetic energy.

Wave power represents a highly promising field in the broader area of green energy and it is currently the subject of increasing research and investments. The wave energy converter (WEC) under study in this paper is a 1:8 scaled prototype of the ISWEC, a device able to harvest sea energy exploiting the inertial effect of a gyroscope. The aim of this work is to validate the numerical simulation model of the device against the results of a wave tank test campaign carried out in INSEAN facilities in Rome. In the first part of the paper the ISWEC dynamic and hydrodynamic governing laws are outlined and implemented in a numerical model. A detailed description of the 1:8 scaled prototype characteristics is provided together with the experimental setup for the tank tests. A wide range of theoretical operating conditions are considered in order to test the system dynamics as well as its control strategy, and it is discussed how different control strategies influence the system behavior and its energy production. In the last part the experimental results are compared with the output of the numerical model, which gives a good prediction of the device behavior.

The aim of this work is to study the propagation of dam-break waves along a hillslope by mean of a physical model (basically i.e. a 3 x 4 m2 plane set downstream of a reservoir) build up in the Hydraulic Laboratory of the Politecnico di Torino. We want to recreate the water surface, to assess the shape of the flooded area and the arrival time of the wave front. The measurement facility is a high resolution CMOS camera. We measure the water height by linking the intensity of the pixels in the acquired images to the real water depth. Preliminary quantitative results are given for the 0°downstream-slope scenario and qualitative results are presented for the case of downstream inclined plane.

Wave power is one of the most rich and promising sources of renewable energy for the future. Approximately 2000 TWh/year can be produced through the exploitation of the wave energy potential. In the past four decades, hundreds of Wave Energy Converters have been proposed and studied, but so far a conclusive architecture to harvest wave power has not been identified. Many engineering problems are still to be solved; these include survivability, durability, and effective power capture in a variable wave climate. Reacting body devices use the inertia of a large mass to generate the reaction needed from the power take off (PTO). Heretically, in the case of a simple inertial mass, optimal control adjusts the dynamic parameters of the PTO, such as the spring constant and energy absorbing damping, to maximize energy absorption. The ISWEC (Inertial Sea Wave Energy Converter) uses a gyroscope to create an internal inertial reaction that is able to harvest wave power without exposing mechanical parts to the harsh o...

In the past four decades, hundreds of Wave Energy Converters (WECs) have been proposed and studied, but so far a final architecture to harvest wave power has not been identified. Many engineering problems are still to be solved, like survivability, durability and effective power capture in a variable wave climate. ISWEC (Inertial Sea Wave Energy Converter) is a system using the gyroscope to extract power. The goal of this paper is to identify an optimal control strategy in order to maximize wave power exploitation of ISWEC. Here we present a new adaptive control technique and the results deriving from its application to an ISWEC device with rated power of 60kW. ISEWC with the new control strategy are finally applied to the test case of Alghero, and the results in terms of power potential and yearly productivity are shown.

The design process of a device for energy harvesting from sea waves is a complex task, which involves many different stages ranging from the initial mathematical models to an extensive field testing. Scale models are a crucial tool to asses the real world device performance and to validate the mathematical models used in the design process. This paper describes the first laboratory campaign of the scale model of an Inertial Sea Wave Energy Converter (ISWEC). The experiments were carried out in the wave tank of INSEAN (The Italian ship model basin, Rome) between February and April 2012. ISWEC uses a gyroscope to create an internal inertial reaction able to harvest wave power without exposing mechanical parts to the harsh oceanic environment. As for other WECs, the theoretically optimal control of ISWEC should be able to adjust the dynamic parameters of the PTO, such as the spring constant and energy absorbing damping, to maximize the energy absorption. The aim of this manuscript is to explore the effect of PTO control parameters on energy production for a given incoming wave