A Numerical Study of Uniform Copper Foam Porous Disk Distribution for Heat Transfer Enhancement in Parabolic Trough Collectors

A computational study was conducted to examine the possible performance improvement of the thermal efficiency of parabolic trough solar collectors by inserting copper foam blocks inside the receiver tube. Ten discs of evenly distributed metal copper foam blocks were placed along the pipe to facilitate heat exchange. Simulations were conducted under stable, incompressible, and three-dimensional flow conditions. The flow within the copper foam domain of the flow system was described using the Brinkman-Forchheimer model, while the fluid domain was controlled by the Navier-Stokes equation. Thus, the energy equation was used for an accurate prediction of the temperature distribution in the entire continuum of fluid and porous media. This thorough method considered environmental elements like typical levels of solar radiation in Iraq from 9:00 AM to 4:00 PM, along with a flow rate variation of 0.3 to 1.5 LPM for simulation. The results indicated that integrating metal foam decreased absorber plate temperature compared to the scenario without metal foam, resulting in increased collector efficiency. The results indicated a 17% increase in thermal efficiency, indicating significant energy savings and improved practicality of solar energy use in arid areas, such as Iraq. The results also showed that the optimal insertion of metal foam with a 30% filling ratio significantly improved thermal performance, resulting in a 76% improvement in mean heat transfer coefficients. These significant findings underscore how properly planned positioning of metal foams can serve as an effective option for enhancing heat transfer efficiency and outlet temperature regulation in PTSC.