Thermal solar collector with tapered tubes for application with traditional heat transfer fluids and inseminated with particles and nanofluids

In energy system, thermal conductivity of the heat transfer fluids is a limiting factor, because it is lower than thermal conductivity of the surface of heat exchangers. To overcome this limit, researchers proposed a new type of heat transfer fluid to improve heat transfer performance, through mixing of traditional heat transfer fluids with solid nanoparticles (<100 nm). This suspension are called nanofluids. The object of this invention, is a solar collector where it is possible to maintain a constant velocity along the bottom pipe and top pipe to avoid sedimentation, such that it can be used with traditional heat transfer fluids and liquid-solid suspensions, as nanofluids. Sedimentation is avoided by using a solution that does not significantly increases pressure drop in hydraulic systems. Besides, this invention does not influence the thermodynamic characteristics of thermal solar collector. In fact, differences between this invention and a traditional thermal solar collector do not interest geometry of the absorber, riser tubes and mechanisms of heat transfer between solar radiation and absorber and its riser tubes.