NOVELTY - The arrangement (3) has a quieting chamber connected to a water source, and another quieting chamber placed downstream of the former quieting chamber along a through flow direction. A partition wall passed between the quieting chambers defines an upper flow-over edge extending along a horizontal transverse direction (5) in which water is passed from the former quieting chamber to the latter quieting chamber. The latter quieting chamber contains a water outlet (6) extending along the horizontal transverse direction in which the water is passed to form a water film (4).    USE - Flow arrangement for a solar system (claimed) i.e. photovoltaic solar system in a building i.e. house.    ADVANTAGE - The quieting chambers contain a quieting lattice arranged in an inlet-side and contributing with high effectiveness to provide uniform water flow over width of the quieting chambers, thus forming a uniformly distributed water film on a solar module in an effective manner, and hence enhancing efficiency of the solar module during weather conditions and geometric conditions of an inclination of the solar module. The arrangement adjusts cooling action and electric efficiency for the solar module in an efficient and reliable manner. The arrangement discharges the water with respect to width of the solar module, so that the solar module is charged with the uniform water film over entire width, and formation of individual zones on the solar module with inadequate or excessively thick water film is avoided. The arrangement avoids formation of non-uniformities in the water film with an exactly horizontal alignment of a threshold edge in a reliable manner. The arrangement includes channels having self cleaning capability, so that contamination or blockage of leaves in an area of the water flow is prevented in an efficient manner.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a solar system comprising an array of photovoltaic solar modules.    DESCRIPTION OF DRAWING(S) - The drawing shows a perspective view of a house having a shed roof and a photovoltaic solar system with a flow arrangement.    Flow arrangement (3)    Water film (4)    Horizontal transverse direction (5)    Water outlet (6)    Building (19)