Bilgisayar destekli sıvılı düzlemsel güneş kollektörlerinin optimizasyonu

Abstract

Abstract Of M.S. Thesis COMPUTER AIDED OPTIMIZATION OF LIQUID FLAT-PLATE SOLAR COLLECTORS M.S. Student : Hüseyin GONERHAN Supervisor : Prof. Dr. -Ing. Gürbüz ATAGÜNDüZ Abstract In Turkey the most common usage of natural and inexhaustible solar energy is done by liquid flat-plate collectors. There is no need complicated technology for manufacturing flat-plate collectors. Therefore there are cheaper than the other systems. In general they consist of one glass cover, one absorber plate which bears pipes, insulation material and one frame. Heat ing and hot water demand have been supplied by liquid flat- plate collectors. * Although in Turkey collectors are manufactured according to Turkish Standarts (TS 3680, TS 3817, TS 4801) one can find collectors with different quality and different sizes. In this present work, under all other constant remaining conditions, i.e., one or two parameters are taken variable and the others kept constant, the influence of the number of pipes, the distance between two pipes, the ratio of width/length of the collector and the material of the absorber plate on the thermal efficiency coefficient and the heat collected by the collector has been investigated theoretically using experimental data. The aim of this work is the design of an optimum liquid flat-plate solar collector with suitable properties such as width/lenght ratio, number ofpipes, distance between two pipes and material. In previous research works, the influence of the material, the material of absorbing plate, the thickness of the absorbing plate, the convective heat transfer coefficient in pipes; the liquid velocity in pipes, the geometry of pipes, the distance between the glass cover and the absorbing plate, the liquid properties, the insulation material and their thickness and the overall heat transfer coefficient on the thermal efficiency coefficient has been investigated, but the ratio of width/length, number of pipes and the distance between two pipes have been not discussed. In addition, at the moment, classically manufactured collectors by the firms which are available in the market have been investigated for the months May, June, July, August and September where the thermal efficiency coefficient curves have been compared under each other and the best thermal efficiency coefficient curve has been determined. In the 1st part of the present work mathematical modelling has been done which bases on the fin theory. By means of the fin theory correlation the outlet temperature of the water and the thermal efficiency coefficient have been calculated. In the second part of the work experiments, in the 3rd part the investigations in details and in the 4th part the results have been discussed. At the end this investigation it has been seen that the thermal efficiency coefficient of a liquid flat-plate solar collector is function of following parameters: - Material of absorbing plate and pipes, - Number of pipes, - The distance between two pipes, - The ratio of width/length, - Outside temperature, - The solar radiation intensity. The optimum liquid flat-plate collector has been obtained for the following data: - Width/Lenght = 1.4/1.4 = 1.0, - Number of pipes =13, - The distance between two pipes = 0.1038 m, - Material of the collector = Copper. The months in which the best thermal efficiency coefficient curve has been obtained are June and July.

Abstract Of M.S. Thesis COMPUTER AIDED OPTIMIZATION OF LIQUID FLAT-PLATE SOLAR COLLECTORS M.S. Student : Hüseyin GONERHAN Supervisor : Prof. Dr. -Ing. Gürbüz ATAGÜNDüZ Abstract In Turkey the most common usage of natural and inexhaustible solar energy is done by liquid flat-plate collectors. There is no need complicated technology for manufacturing flat-plate collectors. Therefore there are cheaper than the other systems. In general they consist of one glass cover, one absorber plate which bears pipes, insulation material and one frame. Heat ing and hot water demand have been supplied by liquid flat- plate collectors. * Although in Turkey collectors are manufactured according to Turkish Standarts (TS 3680, TS 3817, TS 4801) one can find collectors with different quality and different sizes. In this present work, under all other constant remaining conditions, i.e., one or two parameters are taken variable and the others kept constant, the influence of the number of pipes, the distance between two pipes, the ratio of width/length of the collector and the material of the absorber plate on the thermal efficiency coefficient and the heat collected by the collector has been investigated theoretically using experimental data. The aim of this work is the design of an optimum liquid flat-plate solar collector with suitable properties such as width/lenght ratio, number ofpipes, distance between two pipes and material. In previous research works, the influence of the material, the material of absorbing plate, the thickness of the absorbing plate, the convective heat transfer coefficient in pipes; the liquid velocity in pipes, the geometry of pipes, the distance between the glass cover and the absorbing plate, the liquid properties, the insulation material and their thickness and the overall heat transfer coefficient on the thermal efficiency coefficient has been investigated, but the ratio of width/length, number of pipes and the distance between two pipes have been not discussed. In addition, at the moment, classically manufactured collectors by the firms which are available in the market have been investigated for the months May, June, July, August and September where the thermal efficiency coefficient curves have been compared under each other and the best thermal efficiency coefficient curve has been determined. In the 1st part of the present work mathematical modelling has been done which bases on the fin theory. By means of the fin theory correlation the outlet temperature of the water and the thermal efficiency coefficient have been calculated. In the second part of the work experiments, in the 3rd part the investigations in details and in the 4th part the results have been discussed. At the end this investigation it has been seen that the thermal efficiency coefficient of a liquid flat-plate solar collector is function of following parameters: - Material of absorbing plate and pipes, - Number of pipes, - The distance between two pipes, - The ratio of width/length, - Outside temperature, - The solar radiation intensity. The optimum liquid flat-plate collector has been obtained for the following data: - Width/Lenght = 1.4/1.4 = 1.0, - Number of pipes =13, - The distance between two pipes = 0.1038 m, - Material of the collector = Copper. The months in which the best thermal efficiency coefficient curve has been obtained are June and July.