The utilization of conical strip inserts in a parabolic trough collector

  • Keyvan Amani
  • Mahdi Ebrahimpour
  • Sanaz Akbarzadeh
  • Mohammad Sadegh ValipourEmail author


During the last years, many studies have been performed in the field of parabolic trough collectors (PTCs) to achieve thermal performance enhancement. The use of turbulators can help to increase the fluid mixing and as a result, the decrease in wall temperature and risk of tube deformation. In this paper, the impact of conical strip inserts on the thermal performance of a PTC is numerically investigated. Reynolds number varies from 8000 to 40,000. Working fluid temperature at the inlet is 300 K. The results demonstrate that the Nusselt number increases up to 91.949%. Furthermore, the friction factor in the PTC with conical strip inserts is 5.21 more than the plain tube. Performance evaluation was used for analysing the benefits of this kind of turbulator. The overall thermal–hydraulic performance (PEC) varied from 1.107 to 0.679.


Parabolic trough collector Thermal performance Conical strip inserts Nusselt number 

List of symbols


Adjustable constant (–)


Adjustable constant (–)


Adjustable constant (–)


Friction factor (–)


Turbulent kinetic energy (m2 s−2)


Nusselt number (–)


Prandtl number (–)


The absorber tube diameter (m)


Reynolds number (–)


Temperature (K)


Velocity (m/s)


Velocity in the z direction (m s−1)






Greek symbols


Turbulent kinetic energy (J kg−1 s−1)


Dynamic viscosity (kg m−1 s−1)


Kinematic viscosity (m2 s−1)


The equation of turbulence kinetic energy generation (–)


Adjustable constant (–)


Adjustable constant (–)



Computational fluid dynamics


Finite volume method


Monte Carlo ray tracing (MCRT)


Parabolic trough collector


Thermal performance factor



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Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2020

Authors and Affiliations

  1. 1.Faculty of Mechanical EngineeringSemnan UniversitySemnanIran

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