Heat Transfer Enhancement in Flow Pipe of Solar Parabolic Collector

The objective of this work is to present a novel thermal study of absorber/receiver circular pipe of parabolic trough solar collector system for laminar and turbulent (k-ɛ model) fluids flow. Using CFD ANSYS FLUENT software, a two-dimensional numerical simulation is performed on the enhanced flow and heat transfer fluid of air in PTC receiver pipe. In both the laminar and turbulent flow regimes, the findings showed significant improvements in heat transfer, velocity and temperature drop also, the pattern of temperature distribution over the pipe absorber is exhibited and velocity vectors, pressure contours, temperature contours are analyzed. Velocity drop increases and pressure drop decreases with increasing distance along center line axis towards outlet line of receiver pipe. The effect of increasing heat flux towards pipe wall is presented; it causes increasing of wall temperature (from 350 to 390 K in laminar flow and from 310 to 325 K in turbulent flow). Additionally, Nu number, Fr, and Cd for heat transfer laminar and turbulent flows fluid were calculated. The thermal performance factor of PTC is estimated and it is found 74% in laminar flow condition.