Reaction Turbine Research Articles

Derivation of Power Density Equation of Hydro Turbine: Mathematical Basis of Osmosis Energy to Rotate a Reaction Turbine

Derivation of Power Density Equation of Hydro Turbine: Mathematical Basis of Osmosis Energy to Rotate a Reaction Turbine

Design and Study of a Sediment Erosion Test Device for a Single-Flow Channel in the Guide Apparatus of a Reaction Hydraulic Turbine

Sediment erosion damage is one of the main causes of structural failure in reaction turbine units. To study the mechanism through which sediment erosion affects the water-guiding mechanism of a reaction turbine unit, this study obtained the average concentration and particle size of sediment during the flood season based on the statistics of the measured sediment data from the power station. Additionally, the characteristics of the solid–liquid two-phase flow of the diversion components of the reaction hydraulic turbine were numerically calculated. Based on the velocity triangle change in the guide apparatus and the flow similarity principle, a flow-around wear test device for the guide apparatus of the reaction turbine was designed. Furthermore, the similarity of the sand–water flow field between the guide apparatus of the prototype unit and the test device was compared and analyzed. The results demonstrated that the sand–water flow field of the diversion components of the prototype unit was axisymmetric and exhibited a potential flow distribution. Additionally, uniform sand–water flow occurred within the guide apparatus, with a small sand–water velocity gradient near the wall of the stay vanes (SV) and the guide vanes (GV). The maximum volume fraction of sediment particles was observed in the tailing area of the spiral casing, indicating an enrichment phenomenon of sediment particles. The velocity of the sediment particles on the surface of the guide vane in the single-channel sediment wear test device and prototype unit ranged from 6.2 to 7.8 m/s, and the velocity of the sediment particles on the surface of the stay vane ranged from 5.1 to 14.6 m/s, and the difference of the sediment particles’ velocity near the wall was 1 to 3 m/s. The trailing vorticity of the guide vane reached a maximum of 120 s−1. Consequently, the single-channel sediment erosion test device can unveil the sediment erosion mechanism of the guide apparatus of a reaction turbine.

Improved Operation and Method of a Reaction Turbine for Enhancing Net Head

In a reaction turbine, the amount of energy harnessed depends on discharge and net head. The two variables are mutually exclusive or in which one variable is dependent on another and in which the increase of head will decrease the flow required by the hydraulic turbine or vice versa. There is a need for improving the existing hydropower system and the method for enhancing the net head of a reaction turbine is essential. The present invention will hold the key in novelty during the design and excavation of tail race channel or for Renovation, Modernization and Uprating (RMU) of the existing old hydro power plants. The proper redesign of tail water channel, selecting suitable width, depth and by adopting flow regulating means will yield improve the net head substantially and thereby saving of discharge to an extent. The present invention enables to improve net head and saves discharge considerably, thereby enhancing the capacity factor of the hydro plant. The novelty and the innovation is granted an Indian patent for the method of enhancing the net head of a reaction turbines.

The design and testing of a high reaction turbine blade profile

In order to improve the efficiency of high pressure cylinder of 50∼350MW steam turbine and reduce the manufacturing cost, a steam turbine blade profiles are designed. The numerical simulation and test study of the new blade profile are carried out, and the performance of the new blade profile with variable inlet angle and mach number is discussed, and the performance of the new blade profile is improved when applied to stage environment. The results show that the performance of variable inlet angle and variable mach number of the new blade profile is better than that of the original profile. The aerodynamic efficiency of the new blade profile is obviously better than that of the original profile. The blade loss of the new design profile is lower than the original profile, and the aerodynamic efficiency of the new design profile is obviously better than the original profile. The stage test results show that the efficiency of the new design profile increases by about 0.5% compared with that of the original profile.

POTENSI PEMBANGKIT LISTRIK TENAGA MIKROHIDRO DENGAN TURBIN KAPLAN PADA SUNGAI MAMBAL

The Kaplan turbine is a type of reaction turbine that utilizes potential energy to generate motion energy. The Kaplan turbine is very suitable for use in places where the head is low but requires a large discharge. Currently Kaplan turbines are still very little used in Indonesia, especially in Bali. So that it is difficult to obtain specification data relating to Kaplan turbines. Many prototypes are made on a laboratory scale to get maximum results. This study discusses the results of the output voltage, current, power, and efficiency that can be produced by a PLTMH prototype using a Kaplan turbine. This study also discusses the analytical study of the existing hydropower potential, namely, the water flow rate and the height of the water fall (head) of the Mambal River water flow. This prototype test uses a water flow rate of 6 L or 0.006 m^3/s with a guide vane angle of 30 º and a total of 5 runner blades. In the no-load test, the average turbine rotation before being coupled to the generator was 556 rpm, the average turbine rotation after being coupled was 353 rpm. The average result of the largest turbine rotation is 303 rpm, the largest generator rotation result is 499 rpm, the largest generator voltage average result is 5.60 volts, the largest average generator current result is 0.61 Ampere, the result the largest average generator powerKey Words : Prototype of PLTMH, Kaplan Turbine, Water Discharge, Output producedis 1.93 Watt, the largest torque is 0.14 Nm, the largest PLTMH efficiency is 5.1%.

Optimization Design and Simulation Approach of an Axial Inward Flow Reaction Turbine Incorporating with Organic Rankine Cycle

The demand for sustainable and efficient energy conversion systems has led to the exploration of various turbines design and working fluids. This study focuses on the design and simulation investigation of an axial inward flow reaction turbine utilizing organic fluids as the working medium. Organic fluids have gained attention due to their favourable themodynamic properties and low environmental impact. The selection process for the working fluid takes into consideration factors such as temperature limitations fluids availability and efficiency. The design process begins with a thorough analysis of the fundamental principles govering inward flow reaction turbines. Fluids flow path, blade profiles, the interaction between the fluid and these blades are carefully studied. Design parameters such as specific spedd, specific diameter and specific speed coefficient are determind to ensure optimal turbine performance

Aerodynamics of Tip Leakage Flows Near Partial Squealer Rims In an Axial Flow Turbine With and Without Wall Motion

The objective of present investigation is to study aerodynamics of tip leakage flows near partial squealer rims in an axial flow turbine cascade with and without end wall in motion. The reaction turbine blade used in the present investigations has a blade length of 400 mm and a geometric deflection of 82°. The blade chord is 102 mm with an aspect ratio of 3.9. The tip gap is maintained at 2% (2.04 mm) and the squealer rims were of 1.02 mm height. A total of seven cases were investigated with different squealer geometries including case without squealer rim. The coefficient of secondary loss coefficient (CSKE) is used as objective function. Minimum CSKE indicates minimum losses. From the investigations it is concluded that full suction side squealer rim is the optimum squealer geometry among all cases studied as CSKE was found to be minimum for this geometry. The optimum case was selected for wall motion studies. Three wall motions, namely; 75%,100% and 125% of the inlet meridional velocity were maintained and investigated. The CSKE is reduced with all three end wall motions except very close to the end wall. The exit flow angle is reduced near the end wall as compared to no wall motion.

Comparison of an impulse and a reaction turbine stage for an ORC power plant

Comparison of an impulse and a reaction turbine stage for an ORC power plant

System and method for enhancing a net head of a reaction turbine

The most useful form of renewable energy is Hydropower. This holds 16–20% share of total energy generation. Reaction type hydro turbines are predominantly used due to its advantages on the operation under high flow and low/medium head and high discharge. This paper proposes a system and method for enhancing a net head of a turbine by the way of proper design consideration of tail race channel. The system includes a reaction turbine including scroll casing, guide vanes, and a draft tube. Further, the system also includes a first flow regulating means which reduces a water level in the tailrace to a minimum threshold level from a maximum threshold level when the reaction turbine is operating at a load power corresponding to a high load and maintains the water level in the tailrace to the minimum threshold level to avoid cavitation during the flow of water in the tailrace, thereby enhancing the net head of the reaction turbine. The guide vanes and multiple runner blades reduce a flow rate of the water discharged from the draft tube upon operating on an arrangement of the guide vanes and the multiple runner blades, upon enhancing the net head of the reaction turbine.

Techno-Economic Evaluations: An Innovative of Hydraulic Reaction Turbine for Pico-Hydro Generation System

The primary goal of this paper is to evaluate an innovative Z-Blade turbine technology and its potential implications for production costs and manufacturing techniques. From literatures, conventional pico-hydro technologies with a capability of less than 5kW are getting more and more attention as good alternatives to environmentally friendly power generation, but there are more expensive and complex for small power generation and small domestic consumer level. Therefore, a Z-Blade reaction turbine technical and environmental processes as well as financial research are described in-depth. The methods for a Z-blade turbine design and implementation are described here, and also the material using for the Z-Blade turbine is a grey PVC pipe. Moreover, empirical description, designation, costing, and correlation are employed in the process of critically analysing the simple reaction water turbine novels. Also in this article, the manufacture of the Split Reaction Turbine (SRT) and Cross Pipe Turbine (CPT) was re-evaluated to take into consideration the technological and economic factors as well as the difficulties of both turbines. In the meantime, low-head, low-flow water resources used to examine additional features of Z-Blade. Theoretically, such a platform for hydro production is cost - effective and has a simplistic design methodology with a total cost of USD76 that equates to 7.6% of the overall installation cost and worthy of output up to 115W of mechanical energy.

Topography and size optimization of composite structure to control buckling temperature and thermal buckling mode shape

Composite material has been widely used in the engineering field because of its excellent fatigue and corrosion resistance and good impact resistance. However, the structural instability of composite structure is observed due to the thermal buckling phenomena when applied with heat. The present study aims to achieve the thermal structural stability of composite plate structure by developing a topography optimization method and a size optimization method to control linear buckling temperature and thermal buckling modes. In this study, the nodal positions or the shell element thicknesses are set as the design variables. The buckling temperature values and buckling mode shapes are included in the objective function. The developed optimization methods determine the optimal thickness distributions and geometries of composite structure, to induce the target buckling temperatures and target buckling mode shapes. To demonstrate the validity of the present approach, several structural optimization problems considering composite plates are solved. The proposed optimization methods allows the convergence of buckling temperatures within 1% range, and that of buckling mode shapes to desired geometries. In addition, the engineering application of the optimization method on reaction turbine blade is presented. The results of this study support the implementation of the topography and size optimization methods to achieve the optimum structural designs for various engineering applications regarding buckling temperature and thermal buckling mode shape.

Innovative small axial multistage turbine with partial admission for bottoming ORC

The expander is the key element of an organic Rankine cycle (ORC) and has a significant influence on the cycle efficiency. Therefore, in this study, an innovative small axial multistage turbine with partial admission for a bottoming ORC (ORBC) is investigated. The ORBC was used for the waste heat utilization of exhaust gases and jacket cooling water from a 537 kW biogas internal combustion engine (ICE) .The initial design of the turbine flow part was developed using a mean diameter two-dimensional (2D) preliminary design (PD) method. The high rotational speed of the axial turbine, which is its most critical characteristic, was overcome by employing partial admission. To achieve high isentropic efficiency, new (nonstandard) profiles of the nozzle and moving blades were designed using an analytical method. The initial full flow part of the turbine was further investigated by three-dimensional (3D) computational fluid dynamics (CFD) simulations, with the aim of improving its design. The simulations also provided a better insight into the physics of flow than the mean diameter 2D method. Both the 2D PD calculations and 3D CFD simulations were performed using real gas properties.The innovative axial action–reaction turbine with partial admission has 8 stages, a mean diameter of 140 mm, and a rotational speed of 9000 rpm. According to the CFD simulation results, a mass flow of isopentane as the working fluid of 1.171 kg/s achieves an effective power of 60.35 kW and isentropic efficiency of 74.8%. These represent an 11.2% increase in the overall power and a 4.5% increase in the overall thermodynamic efficiency by employing an ORBC on a 537 kW biogas ICE.Therefore, the new turbine is competitive with other expanders in this power range.

Experimental Evaluation of Axial Reaction Turbine Stage Bucket Losses

The article describes the measurement methods and data evaluation from a single-stage axial turbine with high reaction (50%). Four operating modes of the turbine were selected, in which the wake traversing behind nozzle and bucket with five-hole pneumatic probes took place. The article further focuses on the evaluation of bucket losses for all four measured operating modes, including the analysis of measurement uncertainties.

Parametric analysis on a simple design water reaction turbine for low-head low-flow Pico-hydro generation system

This paper presents a parametric analysis of the outward flow reaction type turbine known as a Z-Blade turbine for low-head low-flow conditions. By applying the principles of mass conservation, momentum and energy, a nomogram was designed to investigate the theoretical performance characteristics. Based on the parametric analysis and the governing equations and experimental results, attempts have been made to prove that the mass flow rate, angular speed, centrifugal head, power output and efficiency respond dynamically to the water head, radius of the rotor, size of the PVC pipes and the nozzle exit area. A turbine with a 1” pipe diameter gives a higher performance compared to a 1/2” pipe diameter, and certainly the performances of both pipe sizes are improved when the supplied potential energy is increased. This innovative turbine has a maximum rotational speed at an optimum turbine diameter at 0.6m, accompanied by a point where there is a sudden reduction in the water flow rate, where previously the increment in the water flow rate was very high. This can shows from the outcome nomogram with 1” pipe diameter can perform 350 rpm speed with 1.48 L/sec water flow. The Z-Blade turbine has been examined and has shown good potential to be used for low-head (3m, 4m and 5m) and low-flow (less than 2.5 L/sec) conditions.

Design and Analysis of Steam Turbine Rotor Blade

Abstract: A steam turbine is a tool that extracts thermal electricity from pressurized steam and makes use of it to do mechanical work on a rotating output shaft. The steam turbine offers the better thermodynamic performance with the aid of the usage of a couple of levels inside the growth of steam. The levels are characterized by using the manner of strength extraction from them is considered as impulse or reaction mills. On this work the parameters of steam turbine blade various and evaluation is carried out for electricity, existence and warmth switch fees. The varied parameters are the ratio of x-axis distance of blade profile with the aid of chord length and ratio of maximum peak of blade profile in y-path to the chord period. The three-D modeling is executed by way of using Catia software program. The Ansys software is used for static, thermal analysis, subsequently concluded the best design and material (haste alloy, chrome steel, inconel 600) for steam turbine blade, after steam turbine blade imported the stl record 1:2 ratio in to 3-d printing we carried out fast prototyping technique. Keywords: Steam Turbine, Thermal Energy, Impulse Turbine, Reaction Turbine, Static Analysis, Thermal Analysis

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

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.

Turbine Test Rig to Investigate Flow Instabilities in Draft Tube

Time-dependent phenomena in a reaction turbine such as rotor-stator interactions (RSI) and rotating vortex rope (RVR) contribute to pressure fluctuations, vibrations, and even failure of the machine. A small scale test rig is being developed to investigate RSI and RVR and to study RVR mitigation methods. The test rig is designed for a maximum available head and discharge of 8 meters and 0.05 m3/s, respectively. Provisions are made to operate the test rig in open and closed loops. The test rig is flexible to operate for the turbines of high specific speed (high head Kaplan turbine or very low head Francis) to low specific speed (high head Francis). The runner of the test rig is 200 mm in diameter at draft tube inlet. The turbine is connected with a variable speed generator to run up to 1000 rpm. This paper presents the design and arrangements of the test rig components according to the head and discharge conditions. Scale down design calculations for a model are performed using IEC 60193.

Proper orthogonal decomposition of turbulent swirling flow of a draft tube at part load

A large scale vortical structure, i.e., rotating vortex rope (RVR), generally forms at part load (PL) operation of a reaction turbine due to the combined effect of swirling flow at the runner outlet and the adverse pressure gradient in the draft tube. Even with the data analysis through advanced measurement techniques like Laser Doppler velocimetry (LDV) and Particle Image Velocimetry (PIV), the information available about the flow instabilities developed due to RVR is still incomplete. This paper presents an application of the proper orthogonal decomposition (POD) method to analyze the flow field inside the draft tube cone at PL operation of a high-head model Francis turbine. The POD analysis is performed on 250 PIV snapshots containing the axial and radial velocities. The results show that the first eight modes contain more than 95% of the total kinetic energy (KE) of the flow field and are associated with the organized motion of the flow. The first mode contains more than 50% of the total energy, and the axial velocity profile reconstructed with the first mode is identical to the mean axial velocity flow field. The maximum dissipation of the turbulent kinetic energy (TKE) occurs through unorganized motion.

Investigation of the performance and flow characteristics of two-phase reaction turbines in total flow geothermal systems

In a total flow geothermal system, the two-phase turbine can generate output power and recover fresh water for the water-deficient area. The performance of the two-phase turbine under various working conditions is significantly affected by operation parameters of the geothermal system. This paper presented performance evaluation methods of two-phase turbines, including one-dimensional (1D) method, two-dimensional (2D) method and three-dimensional (3D) method. The 1D method was a fast iteration approach and could reflect average flow parameters along the impeller channel. The 2D method included nonuniform effects in the rotational direction and the 3D method could derive the complete 3D flow in the channel using CFD methods. The three models were validated with experimental results under various rotational speeds. Compared with the 3D method, the 1D method and the 2D method could significantly reduce computational time. The performance of the two-phase reaction turbine was evaluated under various working conditions. A correction method based on 1D and 3D results was proposed to generate the performance map and evaluate the influence of operation parameters of the geothermal system on the turbine performance. Proposed methods and analysis can be widely used in the design, selection and operation of two-phase reaction turbines for various thermal systems.

Biomass cogeneration plants integrated into poultry slaughterhouses for reducing industry costs with energy

A technical and economic feasibility analysis was performed concerning biomass cogeneration to supply the thermal and electricity demands of poultry slaughterhouses. The analysis considers measured data referring to the annual energy consumption from an existing industry as well as the characteristics of equipment available in the Brazilian market. The cogeneration plant is equipped with a water tube steam generator and a condensing-extraction steam turbine in a Rankine cycle. Four different configurations were evaluated, including impulse and reaction turbines at two steam pressure/temperature levels (43 bar / 450 °C and 68 bar / 520 °C). A steady state full load operation is considered at cogeneration mode on the weekdays and at Rankine power plant mode on the weekends, when there is no process steam consumption. The technical analysis pointed out the reaction turbine at 68 bar / 520 ºC as the best alternative, leading to the highest overall efficiency. In addition, this plant configuration showed economic advantages represented by an Internal Rate of Return (IRR) of 21%, a Net Present Value (NPV) of US$ 10.93 million, and a payback time of 6 years, enabling a reduction on the industrial cost with energy in the slaughterhouse to 19 US$/ton of product (-30% in comparison to the base case). Finally, the calculated LCOE of 73 US$/MWh was lower than the current price of the electricity in the market, indicating potential economic feasibility of the proposed concept.