D. Kaliakatsos

A calculation method for the estimation of the Linke turbidity factor

A general calculation model is presented to determine the Linke turbidity factor, starting from the experimental datum of global daily solar radiation on the horizontal plane. The model was validated using experimental data for the turbidity factor obtained at Arcavacata di Rende (Cosenza) and at Casaccia (Rome). Moreover, polynomial relations are presented for quick calculation of this parameter on different days of the year for those localities for which the European Solar Radiation Atlas supplies the maximum solar radiation values on clear days.

General calculation methods for solar trajectories

Two calculation methods for solar trajectories are considered, being of general validity and applicable to all latitudes. In addition, some polar and Cartesian solar trajectory diagrams are presented.

Predictive methods to estimate the producibility of PV/T solar collectors

In this work a simple predictive model to estimate PV/T collector performance is presented. The model is based on an equivalent electrical circuit of the collector, whose solution allows evaluation of its thermal and electrical power produced. The electrical circuit is modified according to whether the problem is solved in stationary or transient conditions. As regards the stationary approach, two different circuits can be schematized: the first allows evaluation of the magnitudes at different points along the motion direction of the fluid; the resolution of the second electric circuit allows direct evaluation of the average magnitudes between the inlet and outlet collector section. With the transient model, instead, it is possible to estimate the behaviour of the collector by adding, to the previous circuit, a capacitor of capacity equal to those of the thermal collector. Obviously, when the transient condition is exhausted, the various determined quantities are identical to those measured in stationary conditions. Finally, the study shows that the electrical circuit used for this type of collector is similar to that of the solar thermal collector, with the difference that some circuit components also contain electrical quantities.

Noise Risk Assessment in the Workplace: The Case of a Waste Selection Plant

This paper deals with issues related with the exposure of workers to noise pollution. The aim of the research work is to define and analyse the effects of noise pollution within the working environment. The paper presents the results of the analysis carried out for a company operating various activities of screening, sorting and recycling waste produced in the urban context. Focusing on the company context, the authors studied the operating conditions in which workers performed their activities, they established the methodologies and tools in order to carry out noise measurements and they evaluated the presence of hazardous conditions. Finally, the authors suggest different operational and structural solutions for controlling risks for health of workers and the reduction of noise emissions in the environment.