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Today, the storage and transporting of electricity from one place to another is still an unsolved problem. Besides, it is not economical to install power lines everywhere for low-voltage electronic circuits such as valves which are used to reduce leakage in water lines. When water demand is lower, it is a practical solution to use the pico hydro turbines to supply the required electrical energy for the electronic circuits of the valves used to reduce the losses in the water discharge lines. For this purpose, it is experimentally investigated electricity production in a pico hydro turbine and validated with experimental data that a pico hydro turbine (PHT) generates 1 W electricity under a water flow velocity of 0.53 m/s. It is concluded that the higher resistances were used in the test rig, the less turbine power produced. As the voltage increased, the current obtained decreased, and the turbine power reached its maximum at a resistance of 130 Ω. [ABSTRACT FROM AUTHOR]

Pico hydro turbines are suitable for low head applications in power plants since their efficiency is more stable than other turbine types. In some situations, computational fluid dynamics (CFD) has also been utilized as well as experimental studies for the performance prediction of water turbines at a pico scale. Also, CFD methods are getting much closer to real conditions in terms of steady-state with moving references and transient domains with rotor movements. For this purpose, electricity production related to the flow in a PHT was investigated numerically. This study presents six degrees of freedom (6-DOF) and moving reference frame (MRF) methods to predict the maximum conditions of a pico scale two-dimensional turbine by comparing the torque and angular velocities on the runner based on the turbine output power of 1 W determined by an experimental study. Besides, the effect of the torque, angular velocity, tip speed ratio, and turbine body profile was investigated comprehensively. In this regard, MRF and 6-DOF methods were performed to validate and compare the numerical model with the experimental results. Also, the results obtained from 6-DOF and MRF methods were compared to experimental study. It is concluded that PHT is generating 0.3 W power under 6.47 rad/s angular velocity with 6-DOF method, however; this value corresponds to 31.4 rad/s angular velocity against 1 W with the MRF method. Also, the maximum velocity of the turbine was 6.1 m/s according to the simulation result. It is accepted that the turbine maximum velocity inlet was 0.53 m/s based on the experimental study. As a conclusion, numerical results for the pico hydro turbine were reasonable taking the experimental study into account. It is also concluded that there is a tip speed ratio of 2.36 with the MRF method and 0.48 with the 6-DOF method between water tangential velocity and runner velocity for the turbine model. [ABSTRACT FROM AUTHOR]

The carob, a perennial plant, is grown in regions where the Mediterranean climate is dominant. Because of its properties, it is preferred in many sectors especially in food and health sectors. Carob is mostly used as sugar and molasses. Moreover, seeds of carob are also used as thickening material in the food sector and its residue is utilized as animal feeding stuff as well. Molasses are mostly produced from carob, grape, mulberry, apple and pear for many years in Turkey. Molasses production is different from each other with regard to the structure of each fruit. Molasses are produced by pressing in the event of soft. The molasses of hard dried fruits such as carobs which cannot be pressed are obtained by extraction method using water. The parameters which are important for the quality of product such as extraction temperature and duration are not taken into account in the carob molasses obtained by traditional methods. Increasing the amount of water in extraction decreases production efficiency and quality while increasing energy consumption. In this study, the effects of parameters such as water quantity, extraction temperature, duration and batch number that affect quality of molasses were experimentally investigated by using Taguchi method. [ABSTRACT FROM AUTHOR]