Yoshihito Taniike

Wind Loads Acting on PV Panels and Support Structures with Various Layouts

This study investigates the wind loads acting on ground mounted photovoltaic panels and the support structures thereof with wind tunnel experiments. As a result, observed at the northernmost panel is the minimum wind force coefficient to which the corresponding wind load exceeds the wind load specified in IEC 61215. On the other hands, the maximum and minimum wind force coefficients for the support structures have almost same values in various layouts of PV arrays. This means that the design wind loads for support structures can be determined independent on the array arrangements.

Fluctuating Wind Pressures due to the Conical Vortices on Flat Roofs

When an incident flow attacks to structures with a flat roof at an oblique angle, conical vortices are produced on the roof. The severe suctions are appeared near the windward vertex by the conical vortices. In the case of the delta wing, the steady suctions occur because of the stability of the conical vortices. However, the wind pressures on the roof of the box-type structures are fluctuating, differently from the case of the delta wing. This paper presents the flow patterns on the flat roof of several models with a square section by means of a flow visualization with a laser sheet and a strobe light. The characteristics of the fluctuating wind pressures are also investigated by Proper Orthogonal Decomposition (POD). Based on the results of the flow visualization and the POD analysis, the relations of the conical vortices and the fluctuating wind pressures are studied.