Climate change, environmental impact, and the limited natural resources urge scientific research and novel technical solutions. The monograph series Green Energy and Technology serves as a publishing platform for scientific and technological approaches to "green"i.e., environmentally friendly and sustainabletechnologies. While a focus lies on energy and power supply, it also covers "green" solutions in industrial engineering and engineering design. Green Energy and Technology addresses researchers, advanced students, technical consultants, and decision-makers in industries and politics. Hence, the level of presentation spans from instructional to highly technical. **Indexed in Scopus**.

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In this study, an external melt ice-on-coil thermal storage was studied and tested over various inlet conditions of secondary fluid}glycol solution}flow rate and temperature in charging process. Experiments were conducted to investigate the effect of inlet conditions of secondary fluid and validate the numerical model predictions on ice-on-coil thermal energy storage system. The total thermal storage energy and the heat transfer rate in the system were investigated in the range of 10 l min À1 4 ' V460 l min À1 : A new numerical model based on temperature transforming method for phase change material (PCM) described by Faghri was developed to solve the problem of the system consisting of governing equations for the heat transfer fluid, pipe wall and PCM. Numerical simulations were performed to investigate the effect of working conditions of secondary fluid and these were compared with the experimental results. The numerical results verified with experimental investigation show that the stored energy rises with increasing flow rate a decreasing tendency. It is also observed that the inlet temperature of the fluid has more influence on energy storage quantity than flow rate. consumption, depending on site-specific design, notably where chillers can be operated at full load during the night.Another advantage of thermal energy storage is the ability to use energy more efficiently. Storing energy at night time when the ambient temperature is less than day time is more efficient for the system because of the low temperature of fluid, which enters the condenser. In summer, the system works at a condensing temperature, which is 208C less than daytime, cause 2-3% more efficient usage relative to a system working throughout the day without energy storage (Dincer and Rosen, 2002).A number of studies have been conducted to analyse the thermal behaviour of latent heat thermal energy storage systems. A detailed review about latent energy storage system has been provided by Eckert et al. . It has been determined that the shelland-tube type heat exchanger is the most promising device as a latent heat storage system that requires high efficiency for a minimum volume. In such an energy storing unit, the phase change material (PCM) fills the gap between the shell and the tubes in which heat transfer fluid (HTF) flows, also serves to convey the stored energy to and from the unit. Recently, a theoretical model of the shell-and-tube type unit for storing energy has been reported by Ismail and Alves (1986). In addition, Faghri (1991b, 1992) also has modelled a similar problem at which both the heat charging and the recovery processes have been performed by the circulating fluid. For both models, the shell wall of the unit was assumed to be adiabatic. Using the enthalpy model, the problem of storing energy in a shell-and-tube type unit was also solved by Bellecci and Conti (1993). Cao and Faghri (1991a) have studied the latent heat energy storage systems for both annular and countercurrent flows and numerically determined that the stor...

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In this study, a novel rotating permanent magnetic actuator (PMA) system is proposed to manipulate magnetic nanofluids to pump chemicals inside micro-sized channels with circular paths. The PMA consists of two permanent magnet pairs and a rotor-like structure. A semicircular-shaped microchannel with a square cross-section area is located at the top of the actuator in order to investigate the performance of the PMA. Fe3O4-water magnetic nanofluid is employed as a working fluid for the manipulation inside the microchannel. In the first stage of this work, a numerical survey is conducted to determine the most suitable angular distance between permanent magnets of a pair in terms of generated magnetic field form in the microchannel region and velocity distribution of magnetic nanofluid within the semicircular microchannel when the permanent magnets are stationary. Preliminary experiments are then carried out for the stationary permanent magnets to validate the predicted flow-field results. Performance tests for different PMA speeds (7.5–30 rpm) and particle concentrations (1%–3% by vol.) indicate that it is possible to manipulate the magnetic nanofluid inside the semicircular channel within a velocity range of 58.7–940 µm s−1, which corresponds to a flow rate range of 0.56–9.02 µL min−1. The results confirm that the proposed PMA system provides flow rate requirements in analytical microfluidic applications such as low flow drug delivery (1–10 µL min−1), cell sorting (6.1 µL min−1), and pathogen detection (3–5.83 µL min−1).

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The mechanical and thermal properties of jute fiber/HDPE composites as a function of alkali and oligomeric siloxane treatment of jute fabric were investigated. The effect of surface treatments on the composites was assessed by means of tensile test, short-beam shear test, three-point bending test, SEM, TGA, and DSC. When jute fabric are first treated with alkali solution and then oligomeric siloxane solution, 34% and 49% increases in tensile and flexural strength were observed, respectively. Moreover, it is interesting to note that after alkali and siloxane treatment of jute fabric, 169% increase in ILSS of jute/HDPE composite was obtained. This demonstrates that the adhesion between jute fiber and HDPE matrix is greatly increased by alkali and oligomeric siloxane treatment of jute fabric. This observation was also confirmed by SEM analysis of fracture surface of composites. Alkali and oligomeric siloxane treatment of jute fabric did not considerably change thermal stability and melting and crystallization temperatures of jute/HDPE.