scholarly journals Computational and Experimental Study of the Effect of Solidity and Aspect Ratio of a Helical Turbine for Energy Generation in a Model Gravitational Water Vortex Power Plant

2021 ◽  
Vol 6 ◽  
pp. 213-219
Author(s):  
Shubhash Joshi ◽  
Ajay Kumar Jha
Keyword(s):  
Experimental Study ◽  
Power Plant ◽  
Aspect Ratio ◽  
Computational Study ◽  
Turbine Blades ◽  
Energy Generation ◽  
Ansys Fluent ◽  
The World ◽  
Low Head ◽  
Runner Design

Gravitational Water Vortex power plant is a relatively new plant used to generate hydropower from low head rivers and canals. There has been an increase in research in the field of runner design and canal design for GWVPPs throughout the world. As no definite equations are formulated in case of runners used in a GWVPP, they are currently produced by hit and trial method. This research focuses on studying about the use of a pure reaction turbine, Gorlov turbine, to generate power from a GWVPP. ANSYS Fluent was used to perform computational study while the experimental study was done using helical turbine blades fabricated using a 3-D printer. The energy generated is very low compared to the impulse turbines. Both the computational and experimental study shows that when increasing the aspect ratio of the turbine but keeping the solidity same, the efficiency is increased significantly. However, the studies also show that on increasing the solidity, the efficiency seems to decrease. All the turbines used submerged to 3 different depts and all the results show that increasing the submergence increased the efficiency.

scholarly journals Effect of Blade Angle on Aerodynamic Performance of Archimedes Spiral Wind Turbine

2020 ◽  
Vol 78 (1) ◽  
pp. 122-136
Author(s):  
Andrew Maher Labib ◽  
Ahmed Farouk Abdel Gawad ◽  
Mofreh Melad Nasseif
Keyword(s):  
Experimental Study ◽  
Wind Turbine ◽  
Computational Study ◽  
Computational Simulation ◽  
Turbine Blades ◽  
Aerodynamic Performance ◽  
Small Scale ◽  
Rotational Axis ◽  
Blade Angle ◽  
Archimedes Spiral

Energy harvesting from wind in urban areas is an important solution to meet energy needs and environmental care. This study describes the effect of blade angle on the aerodynamic performance of small-scale Archimedes spiral-wind-turbine blades by computational simulation, which is experimentally validated. Archimedes wind turbine is classified as one of the HAWTs. The computational approach was used to predict the aerodynamic performance of the scaled-down rotor blades. Blade angle is defined by the angle between the rotational axis and the tip of the blade, which varied from 50° to 65° with an interval of 5°. The computational study was carried out using the ANSYS CFX 19 software for a steady incompressible flow. The performance parameters of the wind turbine, which are power and torque coefficients were explored for different blade angles. This was carried out for wind speed from 5 to 12 m/s with an interval of 1 m/s. In order to validate the results of the computational simulation, an experimental study was carried out using a scaled-down 3D-printed models. The experimental study concentrated on the effect of blade angle on the rotating speed for the different turbine models. Obviously, the results highlight that the maximum power coefficient has an inverse relation to the blade angle.

Experimental and Computational Study of Novel Tip Leakage Mitigation Methods for High Pressure Turbine Blades

2015 ◽  
Author(s):  
Mounir B. Ibrahim ◽  
Ralph J. Volino
Keyword(s):  
High Pressure ◽  
Computational Study ◽  
Turbine Blades ◽  
Turbine Rotor ◽  
High Pressure Turbine ◽  
Ansys Fluent ◽  
Tip Leakage ◽  
Blowing Ratio ◽  
Numerical Solver ◽  
Mitigation Methods

This paper presents computational and experimental study of a possible approach to reduce tip leakage losses. The study was conducted on the EEE (Energy Efficient Engine) HPT (High Pressure Turbine) rotor tip geometry. The CFD was done utilizing the commercial numerical solver ANSYS FLUENT. The experimental work was conducted in a low speed wind tunnel with linear cascade at the USNA (for Re = 30,000) and the NASA Transonic Turbine Blade Cascade facility at the NASA John H. Glenn Research Center for Re of 85,000 to 683,000 at two isentropic exit Mach numbers of 0.74 and 0.34 were reported. The overall scope of this study is to investigate how the tip leakage and overall blade losses are affected by injection from the tip surface at the camber line, and the jet blowing ratio. The results identify areas where future investigation can be explored in order to achieve higher performance of the high pressure turbines.

scholarly journals Effects of Geometrical Parameters in Gravitational Water Vortex Turbines with Conical Basin

2020 ◽  
Vol 2020 ◽  
pp. 1-16
Author(s):  
Tri Ratna Bajracharya ◽  
Shree Raj Shakya ◽  
Ashesh Babu Timilsina ◽  
Jhalak Dhakal ◽  
Subash Neupane ◽  
...  
Keyword(s):  
Power Plant ◽  
Mechanical Energy ◽  
Geometrical Parameters ◽  
Performance Tests ◽  
System Efficiency ◽  
Significant Parameter ◽  
Turbine Runner ◽  
Low Head ◽  
Basic Reference ◽  
Runner Design

Gravitational Water Vortex Power Plant (GWVPP) is an appropriate means to convert kinetic energy of water to rotational mechanical energy at the very low head site. This study aims to establish a basic reference for the design of the runner for the Gravitational Water Vortex Turbine (GWVT) with a conical basin. Seven different geometrical parameters have been identified for runner design, and the effect of these parameters on the system efficiency has been studied numerically and experimentally. The effect of these parameters has been studied over the range of speed with torque. The results from performance tests of these runners suggest that runner height is the most significant parameter to be considered in the design of a turbine runner for GWVPP with a conical basin. The results show that the efficiency of GWVT has improved up to 47.85% as obtained from experiments.

Cracks on the Roots of Turbine Blades of the Low-Pressure Turbine in a Steam Power Plant

2015 ◽  
Vol 52 (4) ◽  
pp. 214-225 ◽  
Author(s):  
E. Plesiutschnig ◽  
R. Vallant ◽  
G. Stöfan ◽  
C. Sommitsch ◽  
M. Mayr ◽  
...  
Keyword(s):  
Power Plant ◽  
Turbine Blades ◽  
Low Pressure ◽  
Steam Power ◽  
Steam Power Plant ◽  
Low Pressure Turbine

scholarly journals Optimization Design of Lattice Structures in Internal Cooling Channel with Variable Aspect Ratio of Gas Turbine Blade

Energies ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3954
Author(s):  
Liang Xu ◽  
Qicheng Ruan ◽  
Qingyun Shen ◽  
Lei Xi ◽  
Jianmin Gao ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Aspect Ratio ◽  
Optimization Model ◽  
Lattice Structure ◽  
Turbine Blades ◽  
Internal Cooling ◽  
Cooling Channel ◽  
Cooling Channels ◽  
Mechanical Performances ◽  
Type Lattice

Traditional cooling structures in gas turbines greatly improve the high temperature resistance of turbine blades; however, few cooling structures concern both heat transfer and mechanical performances. A lattice structure (LS) can solve this issue because of its advantages of being lightweight and having high porosity and strength. Although the topology of LS is complex, it can be manufactured with metal 3D printing technology in the future. In this study, an integral optimization model concerning both heat transfer and mechanical performances was presented to design the LS cooling channel with a variable aspect ratio in gas turbine blades. Firstly, some internal cooling channels with the thin walls were built up and a simple raw of five LS cores was taken as an insert or a turbulator in these cooling channels. Secondly, relations between geometric variables (height (H), diameter (D) and inclination angle(ω)) and objectives/functions of this research, including the first-order natural frequency (freq1), equivalent elastic modulus (E), relative density (ρ¯) and Nusselt number (Nu), were established for a pyramid-type lattice structure (PLS) and Kagome-type lattice structure (KLS). Finally, the ISIGHT platform was introduced to construct the frame of the integral optimization model. Two selected optimization problems (Op-I and Op-II) were solved based on the third-order response model with an accuracy of more than 0.97, and optimization results were analyzed. The results showed that the change of Nu and freq1 had the highest overall sensitivity Op-I and Op-II, respectively, and the change of D and H had the highest single sensitivity for Nu and freq1, respectively. Compared to the initial LS, the LS of Op-I increased Nu and E by 24.1% and 29.8%, respectively, and decreased ρ¯ by 71%; the LS of Op-II increased Nu and E by 30.8% and 45.2%, respectively, and slightly increased ρ¯; the LS of both Op-I and Op-II decreased freq1 by 27.9% and 19.3%, respectively. These results suggested that the heat transfer, load bearing and lightweight performances of the LS were greatly improved by the optimization model (except for the lightweight performance for the optimal LS of Op-II, which became slightly worse), while it failed to improve vibration performance of the optimal LS.

scholarly journals A New Computational Method for Estimating Simultaneous Equations Models Using Entropy as a Parameter Criteria

Mathematics ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 700
Author(s):  
Belén Pérez-Sánchez ◽  
Martín González ◽  
Carmen Perea ◽  
Jose J. López-Espín
Keyword(s):  
Experimental Study ◽  
Computational Study ◽  
Estimation Method ◽  
Information Criteria ◽  
Simultaneous Equations ◽  
Estimation Methods ◽  
Entropy Measure ◽  
Economic Science ◽  
Akaike Information Criteria ◽  
Simultaneous Equations Models

Simultaneous Equations Models (SEM) is a statistical technique widely used in economic science to model the simultaneity relationship between variables. In the past years, this technique has also been used in other fields such as psychology or medicine. Thus, the development of new estimating methods is an important line of research. In fact, if we want to apply the SEM to medical problems with the main goal being to obtain the best approximation between the parameters of model and their estimations. This paper shows a computational study between different methods for estimating simultaneous equations models as well as a new method which allows the estimation of those parameters based on the optimization of the Bayesian Method of Moments and minimizing the Akaike Information Criteria. In addition, an entropy measure has been calculated as a parameter criteria to compare the estimation methods studied. The comparison between those methods is performed through an experimental study using randomly generated models. The experimental study compares the estimations obtained by the different methods as well as the efficiency when comparing solutions by Akaike Information Criteria and Entropy Measure. The study shows that the proposed estimation method offered better approximations and the entropy measured results more efficiently than the rest.

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