Thermal Performance of Solar Hot Water Systems Using a Flat Plate Collector of Accelerated Risers

Abstract

This study focuses on a comparison of the performance of two similar locally-fabricated solar water heaters. One of the collectors features a new design for accelerated absorber; its risers are made of converging ducts whose exit area is half that of the entrance. The other collector is a conventional absorber, with risers of the same cross sectional area along its length. Each collector is the primary part of an indirect thermosyphon circulation solar hot water system. Both collectors face south with a fixed tilt angle of 33.3

Recent investigations in solar flat plate collectors

“…Amori and Jaboury [23] compared performance of conventional thermosyphon collector with the thermosyphon collector having riser tubes converging in the direction of flow of water. The circulation/flow rate was considerably higher than for conventional.…”

“…20 Influence of the rings attached on the inside of tubes [13] Water outlet temperature was increased 21 glass cover incorporating lenses [15] Increases the efficiency and outlet temperature 22 Double glazing with an argon gas filled between two glass panes [16] Increases the efficiency 23 Various inserts in tube [19] Mesh insert performs best in laminar regime, in turbulent range, concentric coils is better 24 Porous aluminum absorbers [20] Maximum efficiency for the more porous and thicker absorber at the highest air mass flow rate, but at very low air flow rates the absorber porosity shows a reversed effect 25 collector with heat storage materials such as sand, sand with iron scraps, gravel and gravel with iron scraps [25] Gravel with iron scraps gives better efficiency than other storage materials VII. CONCLUSION Change in geometric features of collectors discussed.…”

“…Tube shape [23] Eficiency and circulation rate improves for converging tubes collector 10 Tube shape [24] Helical pipe collector gives higher temperature in hot water tank 11 Materials used for constructing FPC Absorber plate material [6] Low cost galvanized iron as absorber material can give efficiency comparable to copper 12 Tube and header material [17] Low cost coated stainless steel tube and aluminium tube gives same performance as copper 13 Absorber coating material [2] Higher outlet temperature and higher efficiency for black chrome followed by the matt black and sol chrome 14 Gas filled in the space between Xenon gas has best yield among krypton, absorber plate and glass cover [7] argon and air 15 Cover glass coating material for uncoated absorber FPCs [21] With coating high performance is achieved 16 Het pipe working fluid [11] Acetone gives higher efficiency than methanol and ethanol. Water gives higher efficiency than methanol 17 Other things Use of PCM [5] The temperature of water in PCM filled FPC is much higher 18…”

Convex Lens With Transparent Glass Solar Water Heating System

“…The fluid natural circulation rate increases by reducing size of the riser tube and converging shape cross-sectional is used. The water temperature is more and density lighter in the converging riser, because water content in the converging area is less [4]. Various papers reviewed they have tabulated the flow rate importance to the solar collector performance of the solar water heating system.…”

Experimental Investigation of Solar Flat Plate Collector with Inner Grooved Copper Tube

“…The result showed that there was in increase in thermal performance with a corresponding increase in solar intensity. Amori and Jabouri [6] designed two new flat plate collector; one with accelerated absorber and riser with converging duct whose outlet area is small whereas other one is similar to conventional FPC. The setup was tested with different water withdrawal profiles as well as with horizontal and vertical storage tank having helical coiled tubes and their result showed there was a considerable increase in thermal performance and stratification in the storage tank with respect to design and helical tube insertion.…”