Experimental, Numerical and Application Analysis of Hydrokinetic Turbine Performance with Fixed Rotating Blades

In this study, a hydrokinetic turbine is designed for the high-altitude regions where local electricity network lines are difficult to reach. If there was a stream flow around, electricity production could be possible and necessary because of environmental reasons. The performance of the hydrokinetic turbine was investigated experimentally and numerically. The numerical analyses of the turbine system were performed via MATLAB/Simulink version R2014a. Except power-based performance characteristics, efficiency of the system in terms of installation and necessary investment costs were also investigated. It is calculated that the system to be established on a river with a water flow rate of 30 m3/h will meet the investment cost in approximately 8 years.

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EFFECT OF FLOW STEERING ANGLE TOWARD THE HYDROKINETIC TURBINE PERFORMANCE

EUREKA Physics and Engineering ◽

10.21303/2461-4262.2019.00899 ◽

2019 ◽

Vol 3 ◽

pp. 20-31

Author(s):

Rudy Soenoko ◽

Hastono Wijaya

Keyword(s):

Kinetic Energy ◽

Water Flow ◽

Flow Rate ◽

Turbine Blades ◽

Water Flow Rate ◽

Rate Variation ◽

Steering Angle ◽

Turbine Performance ◽

Hydrokinetic Turbine ◽

Turbine Runner

The kinetic turbine is one of the solutions for use in low-speed river flows ranging from 0.01–2.8 m/s. This kinetic turbine is used as a conversion equipment to convert the water kinetic energy into an electrical energy. The working principle of a kinetic turbine is utilizing and relies on the water kinetic energy. Water flowing into the turbine area will produce a momentum on the turbine blades. This momentum change would then push the turbine blades and finally spin the turbine runner. The aim of research is thedetermination of the effect of water flow steering angle (a) and water flow rate variation in the kinetic turbine performance. This research uses vertical axis kinetic turbines with eight curve blade attached to the turbine runner. The variables used are two values of water flow steering angle, namely 25°and 35°. The water flow rate variation of 30 m3/h, 35 m3/h, 40 m3/h and 45 m3/h. The method used in this study uses a real experimental method. These two variations would then compare with the result of a hydrokinetic turbine performance done on the previous research. The results show that the water flow steering angle a affected the kinetic turbine performance (power, efficiency and torque). From these several water flow steering angle and water flow rate variations, the turbine performance with a 35° water flow steering angle get the highest performance compared with the use of 25° and 14° water flow steering angle. The greater the flow angle and the greater the water flow rate, the greater the torque, power and efficiency. The highest turbine power produced, P=17.5 W, occurs on the 35° water steering angle, and on a Q=45 m3/h water flow rate and on a 80 rpm turbine rotation. While the highest turbine efficiency, h=27 %, occurred on the Q=30 m3/h water flow rate, on a 60 rpm turbine rotation and on a water flow steering angle a=35°. The highest turbine torque, 3.1 Nm, occurs at Q=45 m3/h water flow rate at a maximum turbine braking and on a water steering angle a=35°.

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Effect of Water Flow on Underwater Wet Welded A36 Steel

Metals ◽

10.3390/met11050682 ◽

2021 ◽

Vol 11 (5) ◽

pp. 682

Author(s):

Eko Surojo ◽

Aziz Harya Gumilang ◽

Triyono Triyono ◽

Aditya Rio Prabowo ◽

Eko Prasetya Budiana ◽

...

Keyword(s):

Mechanical Properties ◽

Water Flow ◽

Flow Rate ◽

Water Flow Rate ◽

Physical And Mechanical Properties ◽

Shielded Metal Arc Welding ◽

Effect Of Water ◽

Bending Effect ◽

Metal Arc Welding ◽

A36 Steel

Underwater wet welding (UWW) combined with the shielded metal arc welding (SMAW) method has proven to be an effective way of permanently joining metals that can be performed in water. This research was conducted to determine the effect of water flow rate on the physical and mechanical properties (tensile, hardness, toughness, and bending effect) of underwater welded bead on A36 steel plate. The control variables used were a welding speed of 4 mm/s, a current of 120 A, electrode E7018 with a diameter of 4 mm, and freshwater. The results show that variations in water flow affected defects, microstructure, and mechanical properties of underwater welds. These defects include spatter, porosity, and undercut, which occur in all underwater welding results. The presence of flow and an increased flow rate causes differences in the microstructure, increased porosity on the weld metal, and undercut on the UWW specimen. An increase in water flow rate causes the acicular ferrite microstructure to appear greater, and the heat-affected zone (HAZ) will form finer grains. The best mechanical properties are achieved by welding with the highest flow rate, with a tensile strength of 534.1 MPa, 3.6% elongation, a Vickers microhardness in the HAZ area of 424 HV, and an impact strength of 1.47 J/mm2.

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Design and thermal characteristic analysis of motorized spindle cooling system

Advances in Mechanical Engineering ◽

10.1177/16878140211020878 ◽

2021 ◽

Vol 13 (5) ◽

pp. 168781402110208

Author(s):

Yuan Zhang ◽

Lifeng Wang ◽

Yaodong Zhang ◽

Yongde Zhang

Keyword(s):

Flow Rate ◽

High Speed ◽

Thermal Deformation ◽

Cooling System ◽

Thermal Characteristic ◽

Water Flow Rate ◽

Thermal Characteristics ◽

Characteristic Analysis ◽

Motorized Spindle ◽

Experiment And Simulation

The thermal deformation of high-speed motorized spindle will affect its reliability, so fully considering its thermal characteristics is the premise of optimal design. In order to study the thermal characteristics of high-speed motorized spindles, a coupled model of thermal-flow-structure was established. Through experiment and simulation, the thermal characteristics of spiral cooling motorized spindle are studied, and the U-shaped cooled motorized spindle is designed and optimized. The simulation results show that when the diameter of the cooling channel is 7 mm, the temperature of the spiral cooling system is lower than that of the U-shaped cooling system, but the radial thermal deformation is greater than that of the U-shaped cooling system. As the increase of the channel diameter of U-shaped cooling system, the temperature and radial thermal deformation decrease. When the diameter is 10 mm, the temperature and radial thermal deformation are lower than the spiral cooling system. And as the flow rate increases, the temperature and radial thermal deformation gradually decrease, which provides a basis for a reasonable choice of water flow rate. The maximum error between experiment and simulation is 2°C, and the error is small, which verifies the accuracy and lays the foundation for future research.

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Marine current energy assessment and the hydrodynamic design of the hydrokinetic turbine for the Moroccan Mediterranean Coast

Energy Exploration & Exploitation ◽

10.1177/0144598720986629 ◽

2021 ◽

pp. 014459872098662

Author(s):

Salma Hazim ◽

Abdelouahab Salih ◽

Mourad Taha Janan ◽

Ahmed El Ouatouati ◽

Abdellatif Ghennioui

Keyword(s):

Electrical Energy ◽

Mediterranean Coast ◽

Electricity Production ◽

Blade Element Theory ◽

Hydrokinetic Turbine ◽

Marine Current ◽

Current Resource ◽

Suitable Area ◽

The Impact ◽

Current Energy

Generating electricity through renewable energies is growing increasingly to reduce the huge demand on electricity and the impact of fossil energies on the environment, the most common sources forms used are: the wind, the sun, the photovoltaic and the thermal, without forgetting hydropower by the bays of dams. Fortunately, 70% of our planet is covered by the seas and oceans, this area constitutes a huge potential for electricity production to be exploited. The scientific advances of recent years allow a better exploitation of these resources especially the marine current due to its reliability and predictability. The marine current energy is extracted using a hydrokinetic turbine (HKT) which transform the kinetic energy of water into an electrical energy. The exploitation of this resource needs in the first step the assessment of marine currents in the study area for implementing the HKT, and the second step is designing an adequate technology. The main goal of this study is the assessment of the marine current resource on the Moroccan Mediterranean coast to evaluate the suitable area to implement the HKT, and to determine the marine current speed intensities at different depths. As well as, to estimate an average potential existing in the site. Moreover, we will conduct a study based on the results of the assessment that was made to design a horizontal axis marine current turbine (HAMCT). Two hydrofoil profile were considered to design a HAMCT using the Blade Element Theory (BEM) and calculating their performances adapted to the site conditions Naca4415 and s8052. In addition, a comparison was made between this two HAMCT hydrofoil profile for deciding the best one for implementing in the studied area.

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Experimental Characterization of a Modified Airlift Pump

Volume 7: Fluids Engineering Systems and Technologies ◽

10.1115/imece2014-39899 ◽

2014 ◽

Author(s):

Afshin Goharzadeh ◽

Keegan Fernandes

Keyword(s):

Water Flow ◽

Flow Rate ◽

High Speed ◽

Water Flow Rate ◽

High Speed Photography ◽

Two Phase ◽

Inner Diameter ◽

Airlift Pump ◽

Flow Map ◽

Churn Flow

This paper presents an experimental investigation on a modified airlift pump. Experiments were undertaken as a function of air-water flow rate for two submergence ratios (ε=0.58 and 0.74), and two different riser geometries (i) straight pipe with a constant inner diameter of 19 mm and (ii) enlarged pipe with a sudden expanded diameter of 19 to 32 mm. These transparent vertical pipes, of 1 m length, were submerged in a transparent rectangular tank (0.45×0.45×1.1 m3). The compressed air was injected into the vertical pipe to lift the water from the reservoir. The flow map regime is established for both configurations and compared with previous studies. The two phase air-water flow structure at the expansion region is experimentally characterized. Pipeline geometry is found to have a significant influence on the output water flow rate. Using high speed photography and electrical conductivity probes, new flow regimes, such as “slug to churn” and “annular to churn” flow, are observed and their influence on the output water flow rate and efficiency are discussed. These experimental results provide fundamental insights into the physics of modified airlift pump.

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