A review study on the performance enhancement of solar parabolic trough receiver by various passive techniques

Abstract

This is a new era where the world’s energy consumption is so high and is likely to increase over 60% of current consumption by the year 2030. Therefore, renewable energy should be used most frequently. The most preferred alternative to fossil fuels is solar energy but converting solar energy into usable form is the most challenging part. The conversion to thermal energy is the one option. In the area of solar thermal power generation, a solar parabolic trough (SPT) collector is an effective method. Also, the use of passive methods to enhance the thermal performance of these parabolic trough receivers is currently the researcher’s interest This review study is focused on different types of geometrical modification (Artificial roughness) used to enhance the thermal performance of SPT receivers. Based on the extensive study it has been found that conical strip insert is a very broad field for research as it can enhance the thermal performance up to 5–10 times. Also there are parameters associated with the conical strips like shape, pitch, angle of twist, slant angle, geometry angle, etc. which can contribute to better performance when used in SPT receiver.

Investigation of the Thermo-hydraulic performance of a roughened Parabolic trough collector

“…). (𝑚 = 𝜋 4𝑑 2 𝑟𝑖 𝜌𝑢 𝑖𝑛𝑙𝑒𝑡 The average heat transfer coefficient ( ) is given by: ℎ ℎ = 𝑞/(𝑇 𝑤 -𝑇 𝑓 ) (10) where represents the average heat flux, while the average inner wall temperature is denoted by 𝑞 𝑇 𝑤…”

“…According to the literature, PTCs' performance can be enhanced through different techniques [2][3][4], the most common being to increase the thermal performance of the absorber tube [5][6][7][8]. Thermal performance can be increased by using surface enlargement elements in the tube [9][10][11][12]. A comprehensive review of more than 200 studies has been reported in the literature and work that has been done in enhancing thermal performance enhancement of PTC systems by using absorber tubes with surface enlargement elements and nanofluids [5].…”

“…The inner profile of the absorber can be modified by corrugation of the absorber tube walls or by adding inserts of different shapes and sizes along the center line of the tube. A variety of experimental, analytical and numerical studies have been carried out to investigate the performance of PTCs with different corrugation elements and inserts [2][3][4][5][6][7][8][9][10][11][12][13]. Different shapes have been investigated from square, triangular, trapezoidal to circular corrugations [14], porous disc receiver [15], internally helically finned tubes [16], unilateral longitudinal vortex generators [17], dimpled tubes [18], dimpled protrusions and helical fins [19], converging-diverging absorber tubes [20], asymmetric outward convex corrugated tube [21], symmetric outward convex transverse corrugated tube [22], internal longitudinal fins [23], pin fin arrays [24], sinusoidal absorber tube [25], internal toroidal rings [26],…”

Experimental analysis of the effect of copper dimple tube with aluminum coating on the performance of parabolic solar water heater using helically twisted tape

“…7 Three primary categories for the many strategies that improve heat transfer are compound active and passive methods. 8 Passive methods don't require external power, whereas active techniques do. 9 Additionally, combining two or more passive methods with one or more active techniques is known as a compound technique.…”