IMPROVED NATURAL CIRCULATION SYSTEM INTEGRATED WITHIN A SOLAR COLLECTOR AND ASSEMBLY COMPRISING A PLURALITY OF NATURAL CIRCULATION SYSTEMS PROVIDED INSIDE SAID SOLAR COLLECTOR

摘要

The invention relates to a natural circulation solar system with for solar collector, said solar collector providing a box-like containment structure (1), closed above by a transparent surface (2), and further providing inside upper absorbing means (3), for the exposure to the solar radiation, arranged inferiorly with respect to said transparent surface (2), a series of independent accumulation primary circuits (21) for the circulation therein of a primary heat carrier fluid, a series of secondary accumulation ducts (5) for the natural circulation of a secondary fluid, and a series of heat exchangers (15) for the exchange of heat between said primary heat carrier fluid and said secondary fluid, said natural circulation system being characterized in that said series of secondary ducts comprise at least an inlet opening (7) and at least an outlet opening (8) of said secondary fluid, said openings being reachable from the outside with respect to said box-like containment structure (1), in that said series of primary circuits (21) comprise at least a first portion, thermally connected to said upper absorbing means (13), and at least a second portion (15) thermally connected to said series of secondary ducts (5), in correspondence with said series of heat exchangers (15), and in that at least one layer of insulating material (4) is provided between said series of ducts of said primary circuit (21) and said series of ducts (5) of said secondary fluid, and in that, when said primary heat carrier fluid flows by natural circulation in said series of primary circuits (21), said primary heat carrier fluid and said secondary fluid circulate in countercurrent in said heat exchanger.