Sustainable production of distilled water using solar desalination systems is becoming more attractive in recent years. Many researchers are trying to enhance the efficiency of such systems. In this study, an improved Parabolic Dish Solar Water Desalination System (PDSWDS) is developed utilizing solar tracking system and finned tube to produce distilled water. The improved solar system consists of solar collector dish to collect solar energy and reflect it to a still tank (receiver) that has the sea water and the system tested in the hot environmental conditions of Iraq. Due to the increased concentration of solar radiation, the temperature is increased inside the still tank causing the water to evaporate. To increase the condensation rate of water vapors, fines are provided over the surface along the length of the main receiver. Sun tracking system is equipped with the dish collector to enhance the efficiency of the solar desalination system. The system used to provide 40 to 50 L of pure water per day, assuming that the structure works about 8 h per day. Results showed increase in temperature of the still tank by 120°C when sun tracking system was employed compared with the system without it in which temperature reached to 71°C. The overall findings of this study show that the thermal efficiency increased by 30
This paper investigates the impact of the incorporated reflector on the dynamic performance of a flat-plate solar collector. To this end, a mathematical model was developed based on the energy balance of the collector’s various components. The equations were then solved using a numerical algorithm. The results show that incorporating the reflective surface into the collector envelope, and despite the energy losses that may result, improves performance by increasing the energy received by the absorber. Within the scope of this study the heat gain between configurations with and without reflection results in a temperature rise of 10.85°C. In particular, temperatures fall with the mass flow rate of the fluid, while they increase with the number of tubes. When the number of tubes increases from 5 to 10, outlet temperatures rise from 38.8–53.95°C for lengths of 1–2.5 m. When the number of tubes increases from 5 to 10, thermal efficiency drops from 60.0–41.6
Thermal energy storage (TES) systems have become advanced technologies for storing and releasing thermal energy during periods of imbalance between energy generation from renewable energy sources and consumption. Phase change materials (PCM) have the capability to store significant amount of thermal energy through latent heat absorption and release. However, thermal energy storage (TES) systems should be designed to accelerate the melting process of the phase change materials. In this study, the influences different fin designs (annular shaped, longitudinal shaped, extruded shaped) on the heat transfer process and phase transition characteristics of a PCM in Latent heat thermal energy storage (LHTES) systems are numerically investigated using finite element method (FEM). Additionally, only charging process was considered in this comparative analysis. Through the thermal assessment, it was found that Model 4 LHTES with extruded fin demonstrated more uniform temperature distribution and faster phase transition during 6-h time interval when compared to other designs of fins. The complete melting of PCM within the Model 4 LHTES with extruded fin was observed at around 3 h and 20 min, whereas the PCM in Model 3 LHTES with longitudinal fins fully transitioned to the liquid at the 3 h and 42 min. In contrast, the PCM in the Model 2 LHTES with annular fins had entirely melted at 4 h, the melting process on Model 1 LHTES without fins was still continue during 6 h period. These numerical results facilitate a more comprehensive understanding of key aspects of fins integration to optimizing future LHTES system design.
One of the main elements contributing to heat loss in buildings is the exterior envelope, which can be improved by employing passive solar systems. This research aims to investigate the Barra–Costantini system’s performance through simulation to obtain the best thermal performance with varying system characteristics, enhance thermal comfort, and reduce energy demand. Three types of glass—single-layer, two-layer, and three-layer—along with various channel dimensions (0.05, 0.1, and 0.15 m) and vent configurations were simulated in a residential building in Mashhad. For a room with a volume of 33.6 m3, the maximum heat gained with a 15 cm depth channel and single-layer glass resulted in an energy saving of 29.1
Use of glass facades is increasing day by day in modern buildings in order to improve the daylight availability and aesthetic views of the building. Lighting load of the building is directly influenced due to daylight through the glass window of the building. Controlling artificial lighting system according to available daylight into the building space reduce energy consumption of the building. However penetration of daylight into the building space increases heat gain which results higher cooling load in most of the places in hot and worm climatic zones in India. External shadings devices are useful means to control heat gain inside the building space and reduces cooling as well as lighting load of the building. The present study focuses on the effect of daylight integration into the building modelled according to National Building Code 2016 (NBC) and Energy Conservation in Building Code 2017 (ECBC 2017) in India through window combinations. Three different daylight conditions and five different windows to wall ratio (WWR) have been studied in Kolkata, India and the result is validated with two other locations situated in higher and lower latitude compared to study location to verify the applicability of the result to other places. The result is compared to a reference building to quantify the benefits of daylight integration with artificial lighting system in terms of long term energy savings and economic benefit.
