Keywords
Solar collector; Parabolic trough; Solar energy; Mini-channel tube; Parallel flow tubes
Abstract
This research aims to use mini-channel flat aluminum tubes with parallel flow in parabolic trough solar
collectors. A parabolic trough solar collector was designed, manufactured, and tested for the present study.
The length of the solar collector was 0.65 m, the collector aperture width was 0.5 m, the radius of the
parabola was 0.25 m, and the rim angle was 90 degrees. In the experimental part, experiments were
conducted at flow rates ranging from 0.1 to 0.8 liters per minute through three distinct heating stages to
evaluate heat transfer efficiency. The results indicated that the largest amount of heat added to the water
was in the case when it passed through the copper tube; the reason for this is the high thermal conductivity
of the copper material and also because of the large amount of solar radiation reflected by the reflective
surface towards the copper tube. In addition, the two stages in which the water passes through the mini-
channel tubes contribute to adding a good amount of heat, helped by their precise design that increases the
heat exchange area between the channels walls and the water. Percentages The maximum efficiency
achieved by the solar collector was 82% at a flow rate of 0.5 l/min at an angle of 125° towards the
southeast in Al-Kut city. Pressure drop analyses revealed a linear relationship with flow rate. This
innovative approach highlights the potential for improved solar energy utilization and represents a major
breakthrough in the performance of solar thermal systems.
collectors. A parabolic trough solar collector was designed, manufactured, and tested for the present study.
The length of the solar collector was 0.65 m, the collector aperture width was 0.5 m, the radius of the
parabola was 0.25 m, and the rim angle was 90 degrees. In the experimental part, experiments were
conducted at flow rates ranging from 0.1 to 0.8 liters per minute through three distinct heating stages to
evaluate heat transfer efficiency. The results indicated that the largest amount of heat added to the water
was in the case when it passed through the copper tube; the reason for this is the high thermal conductivity
of the copper material and also because of the large amount of solar radiation reflected by the reflective
surface towards the copper tube. In addition, the two stages in which the water passes through the mini-
channel tubes contribute to adding a good amount of heat, helped by their precise design that increases the
heat exchange area between the channels walls and the water. Percentages The maximum efficiency
achieved by the solar collector was 82% at a flow rate of 0.5 l/min at an angle of 125° towards the
southeast in Al-Kut city. Pressure drop analyses revealed a linear relationship with flow rate. This
innovative approach highlights the potential for improved solar energy utilization and represents a major
breakthrough in the performance of solar thermal systems.