Design and simulation of air-solar-finned reheating unit: An innovative design of a parabolic trough solar collector

Design and simulation of air-solar-finned reheating unit, an innovative design of a parabolic trough solar collector (PTSC) has been demonstrated in this work. Fundamentally, the design equations were formulated on the optical and thermal principles. The fundamental optical equations were transformed and equated with the original optical equations to realize the optical design functions. The design variables appear in the design function as the unknowns. The design functions were differentiated with respect to the design variables to form design simulatory matrices. Prior to the simulation, the design functions were made to approach zero by the introduction of convergent factors which guarantee the convergence of the simulatory matrices whose final output defines the design variables. The design was algorithmized with a flowchart to justify the design procedures. A slight obtuse-angled rim design was adopted in the design of the reheating unit (RU) which yielded optimum; rim angle of 94°, collector, optical and thermal efficiencies of 0.44, 0.72 and 0.31, respectively, and an optimum exit fluid temperature of $${110^o}$$C sequel to the simulation of the design equations. Besides, the apparent tradeoffs among the design variables were useful in making design decisions. Considering the pitfalls of the traditional acute-angled rim design (AARD), the present work is advocating for the adoption of slight obtuse-angled rim design (SOARD) technique which will shield the PTSCs from the misalignment issues and equally minimize the thermal losses prone to the acute-angled rim design technique. Also, premium on material selection is recommended for the effective operation of RU

SIMULATION OF THE DRYING CHARACTERISTICS OF GROUND NEEM SEEDS IN A FLUIDISED BED

The neem seed is a good source of neem oil as well as insecticides and pesticides. The oil and insecticides can be extracted by two consecutive leaching of neem seed kernels with hexane and ethanol. This work presents a model for simulating the drying of neem seeds in a fluidized bed. Experimental values obtained from literature were used to validate the model prediction. The drying simulation results show that there was a good agreement between the experimental values and the corresponding model predictions

The tropical atlantic observing system

The tropical Atlantic is home to multiple coupled climate variations covering a wide range of timescales and impacting societally relevant phenomena such as continental rainfall, Atlantic hurricane activity, oceanic biological productivity, and atmospheric circulation in the equatorial Pacific. The tropical Atlantic also connects the southern and northern branches of the Atlantic meridional overturning circulation and receives freshwater input from some of the world's largest rivers. To address these diverse, unique, and interconnected research challenges, a rich network of ocean observations has developed, building on the backbone of the Prediction and Research Moored Array in the Tropical Atlantic (PIRATA). This network has evolved naturally over time and out of necessity in order to address the most important outstanding scientific questions and to improve predictions of tropical Atlantic severe weather and global climate variability and change. The tropical Atlantic observing system is motivated by goals to understand and better predict phenomena such as tropical Atlantic interannual to decadal variability and climate change; multidecadal variability and its links to the meridional overturning circulation; air-sea fluxes of CO2 and their implications for the fate of anthropogenic CO2; the Amazon River plume and its interactions with biogeochemistry, vertical mixing, and hurricanes; the highly productive eastern boundary and equatorial upwelling systems; and oceanic oxygen minimum zones, their impacts on biogeochemical cycles and marine ecosystems, and their feedbacks to climate. Past success of the tropical Atlantic observing system is the result of an international commitment to sustained observations and scientific cooperation, a willingness to evolve with changing research and monitoring needs, and a desire to share data openly with the scientific community and operational centers. The observing system must continue to evolve in order to meet an expanding set of research priorities and operational challenges. This paper discusses the tropical Atlantic observing system, including emerging scientific questions that demand sustained ocean observations, the potential for further integration of the observing system, and the requirements for sustaining and enhancing the tropical Atlantic observing system