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In many applications a constant particle size distribution is desired. Various effects lead to size segregation during storage processes. Especially during bunker filling segregation effects are noticed, which are further intensified by possible core flow effects. In this work discrete element simulations were performed to analyze a bunker used for storage of blast furnace sinter, which is filled with a discharging belt conveyor, whereby significant segregation effects are noticed. Several devices including solid state material turbines to reduce segregation during bunker filling were evaluated using DEM. A cross flow turbine is presented, which is proven to significantly reduce segregation effects during bunker filling. The results show a more evenly distributed bunker outflow in terms of particle size. Because sinter is a very abrasive material, the expected wear at the turbine was also estimated with DEM. As the turbine could also be used for energy recovery in other applications, the power output was also investigated. Additionally, the particle breakage due to the cross flow turbine is evaluated in this case. Therefore, a newly developed breakage model for DEM is used. The model is based on a probabilistic particle replacement with voronoi-tessellated fragments. The validated breakage model allows high accuracy in prediction of fragment size distribution. Fragments are further breakable, which allows simulation of processes with several damaging effects. The breakage model was calibrated with a specially developed single particle impact tester for rapid analysis of breakage characteristics of bulk materials. [ABSTRACT FROM AUTHOR]

Instead of connecting the penstock pipe to the nozzle, the connector is also designed to increase the speed of water entry. Therefore, an angle between the connector and the nozzle is needed which is called the connector angle. However, when the connector angle is too large, it can cause the direction of flow at the blade entry is changed. Therefore, this study is intended to compare the performance of the turbine with 3 variations of the connector angle which are 1000, 1050, and 1100. This study is conducted with 2 dimensional computational fluid dynamics analyses. Ansys Fluent 18.1 was used with multiphase volume of fluid (VoF) models. The results of this study reveal that the connector angle affects the performance of the cross-flow turbine. This study shows that a connector with 105° angle generates the higher efficiency compared to connector angle 100° and 110° with highest efficiency value is 83.4%. Additionally, the maximum efficiency of the all cases was obtained at a blade rotating speed of 800 rpm. [ABSTRACT FROM AUTHOR]

The use of computational fluid dynamics (CFD) in cross-flow turbine pico sclae (CFT) numerical simulation is increased in several years using various methods. This study will explain step-by-step of cross-flow turbine pico sclae CFT numerical simulation using six degree of freedom (6-DOF) feature inside ANSYS® Fluent™ 18. The novel method in this study could be applied in future works. The simulation is running in two-dimensional domain and use SST model for turbulence phenomena modelling. Based on analysis, the number of mesh is 64k elements and timestep size of 0.0004 seconds is used because they have error below 1%. The numerical calculation results are lower than experimental results. Moreover, the average deviation between using 6-DOF approach numerical simulation and the experiment results in previous studies of around 6.8%. Thus, the 6-DOF approach can be used for CFT numerical studies. [ABSTRACT FROM AUTHOR]

The industrial sectors in Indonesia is currently growing very rapidly because it is supported by the development of technology in the field of manufacturing. One of the most frequently used machining operations in the manufacturing industry is welding operations. Welding operation is the most efficient and efficient method to combine two or more metal components. The product quality of welding can be obtained by using the production tool (fixture). The purpose of this research is to improve the quality of turbine runner product by using the welding fixture. The method was to design and make welding fixture of turbine runner welding, test the concentricity, straightness of the dish, the stability of the dish to the shaft, and the alignment of the blades to the shaft, and to analyze the deviation of measurement results. Based on the result of welding fixture design of cross-flow turbine runner component, a prototype welding fixture which can facilitate the assembling process of cross-flow turbine runner component was obtained. The conclusions of this research were: 1) The quality of the cross-flow turbine runner product can be increased along with the small geometrical deviation on cross-flow turbine runner using accelerator tool, 2). The maximum deviation of the runner disc placement to the axis of the axis on the 300mm diameter runner is 1.2mm and the runner of 200mm with diameter of 0.68mm, and 3). The assembling time of the turbine runner components is shorter using weld assembly tools with better accuracy. [ABSTRACT FROM AUTHOR]

The exhaust air from the cooling tower has a maximum velocity of 9 m/s and is more constant than the natural wind. This exhaust air stream has a non-uniform velocity profile. The cross-flow wind turbine with 400 mm diameter and 380 mm long are placed above the cooling tower to produce work. Variations in the blade angle and the blade radius of the turbine are tested to determine the effect on the resulting power and turbine performance on the graph of coefficient power (CP) versus tip speed ratio (TSR). The result shows that cross-flow wind turbine with blade angle 45° has higher power than the other blade angle on all radius variation. The cross-flow wind turbine with a 60 mm radius of the blade on 45° blade angle has the highest performance with 2.47 Watt maximum power on 4.31 m/s wind velocity, and Cp is 0.41 on 0.76 TSR. [ABSTRACT FROM AUTHOR]

Nowadays electricity is very important to support various sectors of life. However, as the demand for electricity increases, the source of electrical energy is not enough to supply the energy demand. Indonesia has various potential sources of renewable energy that can be used, one of them is hydropower which in 2018 reached 94.3 GW. But, the utilization of these energy sources has not been maximized because there are limited water turbine manufacturers in Indonesia. This research will develop an application for calculating the design of a Cross Flow water turbine. Cross-Flow Turbine has several advantages, that it is easy to build and has an efficiency that tends to be constant. The calculations include power, rotational speed, speed components, dimensions of turbine components like runners, blades, and nozzles. The application can be used to simulate performance using discharge variations to determine the efficiency of the designed turbine. Also, a Cross Flow turbine is designed with a gross head of 10 meters and a flow rate of 0.4 m3/s. Turbine component calculations are adjusted to the application and manual calculations are used to the validation and application testing. Performance simulation using flow variation of 0.05 m3/s; 0.3 m3/s; and 0.7 m3/s. [ABSTRACT FROM AUTHOR]

This study aims to optimize the flow of irrigation in Taipa Tompobulu village, Maros Regency, Indonesia, to meet the electricity needs of hamlet communities with the construction of micro-hydro power plants. The study was conducted by measuring and calculating the water power that can be produced by the irrigation flow in the Taipa Tompobulu, followed by calculating the electricity needs of the community in the hamlet. If it is feasible, the construction of micro hydro power plant can be done. Construction begins from dams, penstock pipes, turbine houses containing crossflow turbines of rotary transmission systems and generators, construction is also done on power transmission lines and home electrical installations. The results demonstrate that the flow of irrigation in Taipa Tompobulu is feasible as a water resource for the construction of micro-hydro power plants. The construction of micro hydro power plants is able to meet the lighting needs of hamlet communities at night. [ABSTRACT FROM AUTHOR]

The crossflow type turbine is a Banki turbine, which is usually used as a micro hydropower plant. The flow passage that enters through the nozzle usually hits the runner shaft so that the power received by the second stage of the blade was not optimal. This study aims to increase the turbine's power by reducing the diameter of the runner shaft using the drag formulation approach in aerodynamic theory. The 2D design drawings were created using AutoCAD, while 3D models used SolidWorks software. The power output in the first and second stages used a drag force in the CFD simulation. The water discharge was 0.0333 m3/s with a 5.5 m head. The simulated variation of the runner shaft diameter was 32 mm, 30 mm. 28 mm, 26 mm, 25 mm. 24 mm, 23 mm dan 22 mm. The original diameter was 32 mm with a total power of 1656 W. The simulation results showed that the most massive increase was a diameter of 26 mm with a total power of 1699.60 W. Reducing the shaft from 32 mm to 26 mm could increase the power by 2.56%. [ABSTRACT FROM AUTHOR]

This research introduces the Duct Water Current Turbine Triple Helix with very low head less than 2m and water current at river or in the ocean, economical ecological use for small hydro power rating between 100 to 1000 kW still represents an unsolved problem. Unlike conventional hydro installation, water current turbine in open flow and generate power from flowing water with almost zero in environmental impact. Developments in water current turbine design are reviewed and some potential advantages of duct or “diffuser augmented” current turbine and extremely low head turbine will be explored. For the output expected from the project is helical turbine with control flow on duct. The research aims to apply the helical turbine inside the duct to find the parameter of the power coefficient against tip speed ratio λ, pitch angle and twist angle y which is also the optimum parameter to design a helical cross flow turbine with duct. Parameters are obtained from numerical simulation and through the experimental result. For ducted turbines the theoretical limit depends on (i) the pressure difference that can be created between duct inlet and outlet, and (ii) the volumetric flow through the duct. [ABSTRACT FROM AUTHOR]

Cross flow turbine also known as Banki turbine, is a hydraulic turbine that may be classified as an impulse turbine. At present it has gained interest in small and low head establishments because of its simple structure, cost effectiveness and low maintenance. Therefore, the present paper expands on this idea and aims at implementing the Direct Drive Turbine (DDT) for wave power generation. Wave power has enormous amount of energy which is environmentally friendly, renewable and can be exploited to satisfy the energy needs. A Numerical Wave Tank (NWT) was used to simulate the sea conditions and after obtaining desired wave properties; the augmentation channel plus the front guide nozzle and rear chamber were integrated to the NWT. The augmentation channel consisted of a front nozzle, rear nozzle and an internal fluid region which represented the turbine housing. The front and rear nozzle were geometrically identical. Two different nozzle configurations were studied; spiral rear wall type and a straight rear wall type. In addition to this, the effect of front guide nozzle divergent angle was also studied. The general idea is to investigate how different augmentation channel geometry and front guide nozzle divergent angle affects the flow, the water horse power and the first stage (primary stage) energy conversion. The analysis was performed using a commercial CFD code of the ANSYS-CFX. The results of the flow in an augmentation channel of the Direct Drive Turbine in oscillating flow for all the cases are presented by means of pressure and velocity vectors. The water horse power (WHP) and first stage energy conversion for the models are also presented. [ABSTRACT FROM AUTHOR]

The development of a tidal current turbine that can extract maximum energy from the tidal current will be extremely beneficial for supplying continuous electric power. The present paper presents a conceptual design of a 100kW energy integrated type tidal current turbine for tidal power generation. The instantaneous power density of a flowing fluid incident on an underwater turbine is proportional to the cubic power of current velocity which is approximately 2.5m/s. A cross-flow turbine, provided with a nozzle and a diffuser, is designed and analyzed. The potential advantages of ducted and diffuser-augmented turbines were taken into consideration in order to achieve higher output at a relatively low speed. This study looks at a cross-flow turbine system which is placed in an augmentation channel to generate electricity bi-directionally. The compatibility of this turbine system is verified using a commercial CFD code, ANSYSCFX. This paper presents the results of the numerical analysis in terms of pressure, streaklines, velocity vectors and performance curves for energy integrated type bi-directional tidal current turbine (BDT) with augmentation. [ABSTRACT FROM AUTHOR]

The technical potential for hydropower worldwide is between 31 petawatt-hours a year (PWh/y) to 127 PWh/y, while the economic potential is between 9 PWh/y to 15 PWh/y, the report notes. Hydropower, which is the dominant component of renewable energy, is also under the threat of climate change. Climate change has a large impact on water resources and thus on hydropower. Hydropower generation is closely linked to the regional hydrological conditions of a watershed and reacts sensitively to seasonal changes in water quantity. Hydropower is one of the oldest sources of mechanical power and the largest source of renewable electricity generation in use. Global capacity is around 1300 GW. Hydropower is site-specific and so each project will be unique. Hydropower plants are classified according to their size into micro, mini, small, and large hydropower. In terms of generating the capacity the large plants are the most important. These can be either dam and reservoir plants or run-of-river stations. The latter are the easiest to construct and least disruptive, but the former stores energy and is therefore much more flexible in the way it can be used. Energy is taken from hydropower plants through turbines and a number of designs such as Pelton, Francis and Propeller turbine exist to exploit different head heights of water. Most hydropower developments have environmental effects which must be taken into account before constructionHydropower potential is a function of available water and suitable terrain The main advantages of hydropower are low unit cost, low emissions, ease of control and storage. The challenges of hydropower are huge land requirements for storage, soil erosion, ecosystem disturbance and seasonal variability. About 75,000 hectares of land and 14 trillion liters of water are required on average basis to produce 1 billion kWh annually Hydropower plants have a reservoir developed behind a dam to supply water to the hydraulic turbine for generation of a highly flexible, dispatchable electricity supply. Hydropower can be combined with wind, solar and other sources to supply reliable steady and affordable grid electricity. Hydropower can also be exploited from run-of-the-river resources which have less environmental impact but with overreliance on steady supply of rainwater whose supply is unsteady and unpredictable. Apart from power generation, reservoirs can control floods, supply water, and power from stored water even during drought. Hydroelectric electric power plants are useful for grid electricity sustainability particularly during peak hours where plants that generate flexible and cheaper electricity are on high demand. [ABSTRACT FROM AUTHOR]

In this research, the influence of blade geometry on the power stage characterization of cross-flow hydrokinetic turbines and vertical axis under conditions of low current velocity (<1 m/s) has been studied. To carry out the characterization of the power stage, two turbines have been used. The first has three straight blades and corresponds to a SC-Darrieus-type rotor, while the second has three corresponding helical blades with a Gorlov-type rotor. The experimental study has been performed by using a hydrodynamic tunnel and a high precision torque meter with an electric brake, which allows one to obtain the necessary mechanical parameters (torque, rotation speed) for the characterization of the power stage. Analyzing the data obtained from the results of the experimental study, it is determined that, for the same water speed, the Gorlov rotor obtains greater mechanical power than the Darrieus type. In all cases, power coefficient values greater than 1 have been obtained, thus verifying the influence of the blocking phenomenon on the performance of the turbines when they are in confined flow conditions. In turn, the TSR values obtained indicate that these turbines will work mainly by lift since they are higher than unity. [ABSTRACT FROM AUTHOR]

Cross flow turbine can be one of the alternative energies for regions with low wind speed. Collision between wind and the blades which happened two times caused the cross flow turbine to have high power coefficient. Some factors that influence the turbine power coefficient are diameter ratio and blade number. The objective of the research was to study the effect of the diameter ratio and the blade number to the cross flow wind turbine performance. The study was done in two dimensional (2D) computational fluid dynamics (CFD) simulation method using the ANSYS-Fluent software. The turbine diameter ratio were 0.58, 0.63, 0.68 and 0.73. The diameter ratio resulting in the highest power coefficient value was then simulated by varying the number of blades, namely 16, 20 and 24. Each variation was tested on the wind speed of 2 m/s and at the tip speed ratio (TSR) of 0.1 to 0.4 with the interval of 0.1. The wind turbine with the ratio diameter of 0.68 and the number of blades of 20 generated the highest power coefficient of 0.5 at the TSR of 0.3. [ABSTRACT FROM AUTHOR]

In the case of ideal gas turbine gases, isentropic pressure, isobaric heat expansion, and isentropic development follow by isobaric heat rejection take place. When combined, these techniques consider the Brayton cycle, The ideal Brayton cycle differs from the procedure cycle in a number of factors. A few of the present techniques for increasing gas turbine general proficiency include hydration, evaporative cooling, air-cooled pressure refrigeration, single-sort out water-cooled absorption chilling, water-cooled maintenance chilling approach. It features a 22.5° entry angle and a 45° exit angle. With structural, thermal, fatigue and flow studies, our major goal is to boost productivity by altering the cutting edge of the turbine. Even if nothing else, we were able to produce the most important development or approach of a wide range of cutting-edge state degrees, each somewhat for breaks and productivity estimations, and couple it with optimum one. A sharp-edge point, inclination of center of edges, and gas turbine's efficiency are all adjusted as the shaft rotates. Variations in input and exit speed estimates are caused by the edge, and this has a usual effect on the turbine's performance. [ABSTRACT FROM AUTHOR]

Vertical axis wind turbine like cross-flow rotor have some advantage there are, high self-starting torque, low noise, and high stability; so, it can be installed in the urban area to produce electricity. But, the urban area has poor wind condition, so the cross-flow rotor needs a guide vane to increase its performance. The aim of this study is to determine experimentally the effect of Omni-Directional Guide Vane (ODGV) on the performance of a cross-flow wind turbine. Wind tunnel experiment has been carried out for various configurations. The ODGV was placed around the cross-flow rotor in order to increase ambient wind environment of the wind turbine. The maximum power coefficient is obtained as Cpmax = 0.125 at 60° wind direction. It was 21.46% higher compared to cross-flow wind turbine without ODGV. This result showed that the ODGV able to increase the performance of the cross-flow wind turbine. [ABSTRACT FROM AUTHOR]

Cross-flow wind turbine is one of the alternative energy harvester for low wind speeds area. Several factors that influence the power coefficient of cross-flow wind turbine are the diameter ratio of blades and the number of blades. The aim of this study is to find out the influence of the number of blades and the diameter ratio on the performance of cross-flow wind turbine and to find out the best configuration between number of blades and diameter ratio of the turbine. The experimental test were conducted under several variation including diameter ratio between outer and inner diameter of the turbine and number of blades. The variation of turbine diameter ratio between inner and outer diameter consisted of 0.58, 0.63, 0.68 and 0.73 while the variations of the number of blades used was 16, 20 and 24. The experimental test were conducted under certain wind speed which are 3m/s until 4 m/s. The result showed that the configurations between 0.68 diameter ratio and 20 blade numbers is the best configurations that has power coefficient of 0.049 and moment coefficient of 0.185. [ABSTRACT FROM AUTHOR]

Hydroelectricity is electricity produced by the generators that are pushed by the water movement. This is one of the widely used sustainable power. One of the major advantages of the hydro power after constructing the plant is wastage is not created.22% of the word power is generated by hydroelectricity, which constitutes around about 78% of power from inexhaustible natural resources. The yearly hydroelectric creation of India is 115.6 TWh with an introduced limit is 33.6 GW. Miniature hydro is a word utilized for hydroelectric force establishments that commonly produce a power up to 300 KW of intensity. These establishments can give capacity to a disconnected home or little network of sloping territories, or are here and there associated with electric force organizations. There are a considerable lot of these establishments around the globe, especially in agricultural countries as they can give a prudent wellspring of energy without acquisition of fuel. In the current paper an endeavor is made to portray the different parts of miniature hydro for creation of power in uneven regions like site evaluation, development and attributes, job of miniature hydro in supportable improvement and so forth. [ABSTRACT FROM AUTHOR]

Hydro Microturbine is a small device that can generate big amount of electricity from water flow. The simulation will be conducted using three different numbers of blades, namely 6, 7, and 8, blades in order to investigate the effect of these numbers of blade to the turbine movement and flow pressure. The turbine type used was Francis Turbine in 31 mm of inlet diameter, 41 mm of outlet diameter, and 38.75 mm of runner blade diameter. The inlet velocity was 3 ms-1. The numerical calculation was done using ANSYS Fluent. The effect of different numbers of blade due to the water flow velocity will be investigated. The results showed that those with 6 and 7 blades were able to move due to the water flow from the inlet area. Meanwhile, that with number 8 blades produced turbulence inside the turbine. Turbulence happens due to the angle of the guide vane is too small hence it is not suitable for the 8 blades. The results also showed the 7 blades had better performance than that of 6 blades in producing movement velocity and flow pressure. The flow velocity of the 7 blades was 3.56 ms-1, the pressure was 6.473 kPa before entering the blade and 39.6 kPa after exiting the blade. Meanwhile, the flow velocity of 6 blades was 3.1 ms-1, the pressure was 6.482 kPa before entering the blade and 29 kPa after exiting the blade. [ABSTRACT FROM AUTHOR]

Electricity is a very important energy in the modern civilization. It helps us to be productive and improves the quality of living. Kappadi region of Udupi district in Karnataka India, faces many difficult to get access the electric energy. Therefore, it is very important to find new solutions for electric generation in the rural areas (at load centers) which are cost effective and sustainable. This project aims to make use of renewable resources such as hydro energy and convert it into useful electric energy by installing a micro hydro power plant at kappadi. As per the research and based on the calculations there is a probability of generation up to 20kw power from a head of 1.5 to 3.34 meters using bulb turbine. This paper comprises all the data which will help to analyze how power can be generated with less head, also it reveals all methods which were carried out well enough to ensure that this proposal is eximious. [ABSTRACT FROM AUTHOR]

Electricity is a very important energy in the modern civilization. It helps us to be productive and improves the quality of living. Kappadi region of Udupi district in Karnataka India, faces many difficult to get access the electric energy. Therefore, it is very important to find new solutions for electric generation in the rural areas (at load centers) which are cost effective and sustainable. This project aims to make use of renewable resources such as hydro energy and convert it into useful electric energy by installing a micro hydro power plant at kappadi. As per the research and based on the calculations there is a probability of generation up to 20kw power from a head of 1.5 to 3.34 meters using bulb turbine. This paper comprises all the data which will help to analyze how power can be generated with less head, also it reveals all methods which were carried out well enough to ensure that this proposal is eximious. [ABSTRACT FROM AUTHOR]

The paper is developed in the framework of CFD to study the performance of Vertical Axis Turbines (VAT). One direct application is to establish design trends regarding the solidity. The model is validated with benchmarks from the literature for fluvial turbine. As for turbulence models, transitional SST version of k-w is used. The model includes two additional conservation equations for intermittency and critical Reynolds that establishes the transition from laminar to turbulent. Flow pattern are analyzed at intermediate positions along the revolution. A reduction in solidity increases the operation conditions. [ABSTRACT FROM AUTHOR]

An analysis of the impact of hydrokinetic energy technology schemes has been carried out on the following river parameters: water quality, the riverbed and bank stability, sediment dynamics, coastal and aquatic vegetation, fish communities, noise, aesthetics, fishing and riverbed practicability (kayaks and barges). Hydrokinetic energy generation technologies are compared to conventional tidal technologies. Each parameter assessed was evaluated for minor, notable, high, and very high likelihood of constant and temporary exposure. Subordinate elements, such as aesthetics, fishing, and river practicability were determined to be the greatest possible use of hydrokinetic energy schemes in the world rather than river ecosystem elements. The researchers carried out an approximate assessment of the economic indicators because Lithuania does not operate hydrokinetic power plants. An assessment of reduced investment and electricity market energy purchase price indicates that the approximate payback period is six years and the net present value in the seventh year of operation is EUR 7,450. [ABSTRACT FROM AUTHOR]