ANALISIS UNJUK KERJA KOLEKTOR SURYA PELAT DATAR DENGAN PENAMBAHAN SIRIP BERLUBANG BERDIAMETER BEDA SEBAGAI NOSEL YANG DISUSUN SECARA STAGGERED

The solar collector is a device that collects solar radiation and converts it into useful heatenergy. Several types of solar collectors include the parallel flow flat plate solar collector and theperpendicular flow absorber plate solar collector. Previous design of flat plate solar collectorperpendicular flow absorber plate usually uses plates with the same hole diameter. To improve theperformance of this solar collector, modifications have been made by adding perforated fins withdifferent diameters which are arranged staggeredly as an air flow channel or nozzle. The intendedmodification of nozzle diameter is to make the nozzle diameter size different from the large diameter nearthe inlet to the small diameter near the oulet and compared to the reverse nozzle position. Making thediameter of the nozzle near the inlet is larger than the diameter of the hole near the outlet aims to makethe mass flow of air passing through the hole near the inlet larger, so that the flow of air massesexperiences more heat transfer while the diameter of the hole near the outlet is made small is to reducethe mass flow of air which is wasted faster through the outlet channel. With the variation of the holediameter from large to small, it is expected that the heat transfer that occurs in the solar collector will bemore optimal, but it should also be seen in the reverse position. The research was carried outexperimentally. The results of his research show that the useful energy and efficiency of solar collectorswith large to small diameter slotted fins are higher than those with small to large diameter slotted fins.

Thermal–hydraulic analysis of a solar air heater fitted with a wire-roughened absorber plate

This study is to evaluate heat transmission and friction in a rectangular solar air heater with a V-shaped wire rib roughness on the absorber plate that operates in fully formed turbulent flow. Additionally, studies are performed to generate prediction equations for the average friction factor, Stanton number, and efficiency index. The Reynolds number [Formula: see text]–[Formula: see text], angle of attack [Formula: see text]20[Formula: see text]–90[Formula: see text]), relative roughness pitch [Formula: see text]–[Formula: see text], relative roughness height [Formula: see text]–[Formula: see text], and the aspect ratio [Formula: see text]–[Formula: see text] was varied. The efficiency index [Formula: see text] is commonly employed as a thermo-hydraulic performance metric. It is computed as [Formula: see text]. The wire roughness and airflow parameters [Formula: see text] are optimized to maximize heat transfer while retaining minimal friction losses. On the basis of resemblance criteria, average Stanton numbers, average Nusselt numbers, and even average friction factors are derived. The results are compared to those obtained with a smooth absorber duct under similar airflow circumstances in order to assess the increase in heat transfer coefficient and friction factor. The [Formula: see text], and [Formula: see text] have a significant influence on thermo–hydraulic performance, according to these studies. With [Formula: see text], [Formula: see text], [Formula: see text], and [Formula: see text], the optimal configuration geometry for wire roughness and solar air heater duct is identified.

A decomposition solution of variable thickness absorber plate solar collectors with power law dependent thermal conductivity

We present a mathematical model of flat-plate solar collector whose thermal conductivity is a power law function of temperature, and non-dimensional length is governed by a profile index. The rectangular, convex and triangular shape absorber plates are obtained by changing the value of an index of non-dimensional length 0, ½ and 1, respectively. The energy equation governing the temperature of rectangular absorber plate is a non-singular-type equation, and convex and triangular cross-section absorber plate are two different singular type equations. One non-singular and two different singular value equations are solved separately by different operators, as explained separately in classical and modified Adomian decomposition method (ADM) theory respectively. The results obtained for the case of the rectangular, convex and triangular cross-section plate are validated by comparison with the exact analytical solution for special case as available in literature. The effects of various thermo-physical parameters such as power law thermal conductivity parameter, Biot number, aspect ratio, absorbed solar heat flux, overall heat transfer coefficient on the temperature distribution are analyzed.

Enhanced Solar Air Heaters For Crop Drying

Solar air heaters are placed on farms to provide heat for the drying of grain and crop harvesting and harvesting. The results of the thermal study showed that solar air heaters are capable of providing a sufficient increase in air temperature under the majority of crop drying circumstances studied. The restricted thermal capacity of air, as well as the low heat transfer coefficient between the absorber plate and the air flow via the ducting system, both contribute to the overall thermal efficiency of solar air heaters. Solar air heaters must be more efficient in order to be more affordable. This may be accomplished by increasing the heat transfer coefficient between the absorber plate and the air flow passing through the duct. More heat transfer coefficients can be increased by using either active or passive approaches. In most situations, it may be cost-effective to use solar air heaters and incorporate artificial roughness on the absorber plate. The rate of heat transmission from the solar air heater’s duct to the fluid flow may be increased by creating artificial roughness on the surface of the duct. The study focused on several roughness element geometries for solar air heater ducts, and the results indicated that there is a link between the two. This paper attempts to find ways to artificially increase the heat transfer capacity of solar air heaters’ ducts by using element geometries which have been utilised in solar air heaters’ heat transfer devices.

Enhanced Solar Air Heaters for Crop Drying

Solar air heaters are placed on farms to provide heat for the drying of grain and crop harvesting and harvesting. The results of the thermal study showed that solar air heaters are capable of providing a sufficient increase in air temperature under the majority of crop drying circumstances studied. The restricted thermal capacity of air, as well as the low heat transfer coefficient between the absorber plate and the air flow via the ducting system, both contribute to the overall thermal efficiency of solar air heaters. Solar air heaters must be more efficient in order to be more affordable. This may be accomplished by increasing the heat transfer coefficient between the absorber plate and the air flow passing through the duct. More heat transfer coefficients can be increased by using either active or passive approaches. In most situations, it may be cost-effective to use solar air heaters and incorporate artificial roughness on the absorber plate. The rate of heat transmission from the solar air heater's duct to the fluid flow may be increased by creating artificial roughness on the surface of the duct. The study focused on several roughness element geometries for solar air heater ducts, and the results indicated that there is a link between the two. This paper attempts to find ways to artificially increase the heat transfer capacity of solar air heaters' ducts by using element geometries which have been utilised in solar air heaters' heat transfer devices.