Cross-flow Turbine Research Articles

An experimental investigation of the performance of cross-flow turbine: impact of number of blades in runner

ABSTRACT This study examines a cross-flow turbomachine designed for power generation in areas with limited discharge and head availability, focusing on sustainability, affordability, and ease of operation. It investigates how varying the number of blades in the runner affects turbine performance while keeping other design factors constant. Testing runners with 8, 12, 16, 20, and 24 blades under identical conditions reveal consistent RPM variations across different blade numbers for various parameter combinations. The study identifies a 12-blade configuration as optimal for electrification projects at selected sites. Experimental validation using the Taguchi technique confirms the reliability of the findings. Additionally, the research explores the turbine’s performance under different nozzle tip elevations (18 cm, 16 cm, and 14 cm). The highest observed runner speed is 345 RPM for the 12-blade runner at an 8° angle of attack, with similar speeds recorded for the 24-blade runner under similar conditions.

Optimization of the Weir as a Micro Hydro Power Plant in Bayang Nyalo Padang, West Sumatra

The objective of this research is to guarantee that the building of PLTMH Bayang Nyalo achieves maximum energy output and utilizes possible renewable energy sources in a sustainable and efficient manner. This research is a study that aims to describe and analyze data using a quantitative technique. The quantitative research technique is used when study data is in numerical form. Quantitative descriptive research is a method used to examine obtained data by providing a detailed and accurate description of the data. This study aims to determine the optimal value for designing small-scale hydropower plants (PLTMH). In order to do research for this thesis, the author investigates the number of studies performed in the Bead Dam Nyalo Kec. Nagari Bayang North, South Coast Regency West Sumatra. The PLTMH project aims to harness the water flow from the subterranean river, which has a discharge rate of 14.67 liters per second. The power plant is designed to have a power capacity of 623.32 kW, using a high discharge waterfall with an effective height of 5 m. Based on the examination of technological elements, we have reached conclusions: The civil component of this PLTMH includes a gravity concrete dam that is prepared for operation, while the electrical components consist of a Cross flow Turbine. The development of mechanical transmission is ongoing.

Investigation of a cross-flow wind turbine with frontal deflector

Investigation of a cross-flow wind turbine with frontal deflector

Investigation of a cross-flow wind turbine with a hybrid frontal guiding device

Investigation of a cross-flow wind turbine with a hybrid frontal guiding device

Feasibility and sensitivity assessment of various heads for micro-hydropower plant design in the Deluwang watershed, Indonesia

ABSTRACT The escalating global demand for electrical energy, including in Indonesia, underscores the need for renewable energy sources like micro-hydropower plants (MHPs). This study examines the financial feasibility and sensitivity of MHP projects in the Deluwang watershed, Situbondo Regency, Indonesia. Three cases with varying head elevations and discharge rates were analyzed, utilizing crossflow turbines. Case 1, with the highest head and discharge, emerged as the most profitable, demonstrating the highest values for Net Present Value (NPV), Benefit–Cost Ratio (BCR), and Internal Rate of Return (IRR). The study found that on-grid systems, despite higher initial costs, offer more stable revenue and faster payback periods compared to off-grid systems. Sensitivity analysis revealed the on-grid method's resilience to fluctuations in interest rates, project lifespan, and river discharge, maintaining feasibility with up to an 80% reduction in discharge over 15 years. This highlights the importance of strategic planning in MHP design, considering head and discharge rates to optimize power generation. The findings provide valuable insights for renewable energy development, contributing to Indonesia's energy needs and local socio-economic benefits. Future research should further explore the socio-economic impacts of MHP installations to enhance their development and sustainability.

Numerical analysis on hydrodynamic performance and wake recovery of helical-bladed hydrokinetic turbine: Impact of section inclination angle

In the context of exploiting renewable sources, cross-flow helical hydrokinetic turbine is conceded as one of the promising choices to unlock the potential in free-flowing water bodies. This study examines the impact of blade section inclination angle (−10° to +8°) and operational parameters, namely, tip speed ratio (0.6–1.4) and inflow velocity (1.0–2.5 m/s) on the performance as well as wake recovery of a 4-bladed rotor. The coefficients of power and section-averaged mean streamwise velocity deficit values are computed by solving the unsteady Reynolds-Averaged Navier-Stokes equations coupled with k-ε RNG turbulence model using numerical simulations to assess the performance and velocity recovery, respectively. The power coefficients are seen to be improved with an increase in negative section inclination angle and are found optimum in the range from −6° to −10° at a tip speed ratio of 1.0. The simulation results also reveal that the section inclination angle and tip speed ratio parameters significantly influence the velocity recovery. Furthermore, the performance decreases as the inflow velocity increases; however, the wake recovery is unaffected, with an identical wake length of 13 times the rotor diameter along the streamwise direction at a tip speed ratio of 1.0.

Investigation on the Blade Number of Pico-scale Crossflow Turbine for Low Head by Numerical Method

Pico-scale crossflow turbines (CFT) can be an alternative solution to meet electrical energy needs, especially in remote rural areas. CFT is recommended because of its suitability in low head (< 5 m) conditions and fluctuating discharge conditions. One of the parameters that influences the performance of a CFT is the number of blades of the runner. CFT was discovered in 1903 and is still developing; however, the study of the physical phenomena of flow due to the blade number on the energy conversion process has yet to be comprehensively depicted. Therefore, this study aims to analyze the effect of the blade's number of runners on CFT performance using the computational fluid dynamics (CFD) method. The CFD method can visualize the flow field more detail than analytical and experimental. The CFD method is run with a moving mesh feature (transient) and pressure-based solver with a head condition of 3 m. The blades number studied were 16, 18, 22, 24, 26, and 30. Based on the results, the relationship of the CFT efficiency to blade number is described using a second-order multiple regression polynomial, and runner rotation is parabolic. Based on the performance curve, the CFT with 26 blades has the highest performance for low-head conditions.

Numerical Analysis of Flow Velocity and Performance Test of Cross-Flow Turbine (500 W)

The purpose of this study is to analyze the flow velocity and assess the performance of a cross-flow turbine through numerical simulations and performance tests. Using computational fluid dynamics (CFD), the flow patterns and velocity distributions around the turbine blades to gain insights into the turbine's hydrodynamic behavior. In the experimental phase, constructed a prototype of the cross-flow turbine and tested it in a water flume, measuring key performance metrics such as power output and efficiency.The test were performed under design flow condition. The numerical results were validated with performance tests. The numerical analysis revealed critical areas of flow separation and turbulence, which were consistent with the observed experimental data.

Numerical evaluation of low-head inverted cross-flow turbine design method: A comprehensive study

This study aimed to address the challenges of micro-hydropower generation in low-head environments to expand the proportion of hydropower in renewable energy and achieve a carbon neutrality policy. To achieve these goals, various factors affecting the micro-hydro systems, including geographical constraints, construction costs, and grid connectivity, were reviewed and assessed. The results concluded that a novel type of cross-flow turbine with inverted structures, improved the economic feasibility, productivity, and installability of micro-hydropower plants by reducing head losses in open channels or small streams. The parametric studies consisted of four steps: first, designing the initial inverted cross-flow turbine based on the traditional design rules; for the second and third steps, a parametric study for comparing the runner diameter ratio and the number of blades is conducted; and in the last step optimized turbine was designed. The best efficiency point of the optimized inverted cross-flow turbine was 72.92 % at a runner rotational speed of 170 RPM with a 0.75 runner diameter ratio and 35 blades. The optimized turbine was improved by 7.8 % in power and 7.35 % in efficiency, higher than the initial turbine. From the hill chart comparison between the initial and optimized turbine, operation range expansion was confirmed. Overall, this research demonstrates the potential of the inverted cross-flow turbine under low-head conditions.

Modeling Design of Picohydro Power Generation System Using Crossflow Turbine

The goal of this project is to learn how to use a Crossflow turbine to create a Picohydro power plant system modeling. The manufacturing process, from design to evaluation, is the methodology employed. The turbine type utilized is a crossflow turbine, measuring 26 cm in outer diameter, 17.3 cm in inner diameter of the blade runner, and up to 35 pieces of blades. The calculations show that the distance between the blades is 2.3 cm, the blade length is 8.5 cm, the blade width is 4.4 cm, and the radius of curvature of the blade is 2.8 cm. The test results without load obtained the highest turbine rotation of 421 Rpm produces a voltage of 7.29 V before going through the boost converter.

Configuration blade shape for enhancement crossflow turbine performance by the CFD method

The pico scale crossflow turbine (CFT) is a prospect as an independent power plant for remote and rural areas because it has a stable efficiency range of 64 % to 79.5 % in high discharge fluctuation. An alternative to CFT performance enhancement is determining the upper blade configuration to increase lift force. Hence, this study investigates four configurations of the upper CFT blade: convex blade at the centre edge, convex at the trailing edge, convex at the leading edge and ordinary curvature. This research employs a computational fluid dynamics (CFD) method to visualise the flow field. The upper CFT blade configuration significantly affects its performance, and convex at the leading edge has higher performance than others. The performance related to each blade shape's specific speed is parabolic and expressed using empirical law. The empirical law recommends 4.88 as specific speed for designing a pico scale CFT.

PERANCANGAN PLTMH SUNGAI YEH HA DI KARANGASEM DENGAN TURBIN CROSSFLOW

Yeh Ha River in Ababi Village, Karangasem Regency, Bali, is a river that originates from the Yeh Ha springs and is used as a bathing place. This river has the potential for a new renewable energy source that can be utilized for the Micro Hydro Power Plant (MHPP). Discharge measurements were carried out for a week on one of the Yeh Ha spring source channels during the dry season. The results showed an average discharge of 0.201 m3/s. The discharge data used is the minimum potential energy that can be absorbed. Based on the measured discharge data and the used head of 4.6 m, the Tanaka Suiryoku Turbine Selection Chart shows that the crossflow turbine meets the turbine selection criteria. The results of the analysis and calculations show that the available power at the turbine is 8 kW with an efficiency of 80%. A 3-phase synchronous generator with a permanent magnet rotor was selected based on a comparison of the types, specifications, and characteristics of the generator to match the turbine capacity. The output power generated by the generator is 6 kW with a rotational speed of 1500 rpm and a generator efficiency of 90%.

ANALISIS EKONOMI SISTEM PLTMH DAN POMPA AIR SUNGAI YEH HA DI KABUPATEN KARANGASEM

Yeh Ha River in Ababi Village, Karangasem Regency, is a bathing spot utilized by locals for various purposes, fed by the Yeh Ha spring. Among its uses is filling a water tank with a capacity of 58.74 m3 to distribute water to 10 households. Initially, a waterwheel powered a mechanical pump without electricity. However, due to damage, a less efficient hydraulic ram pump replaced the waterwheel. The research aims to design a Microhydro Power Plant (PLTMH) and a water pump system. With these systems, it's expected to enhance the efficiency of filling the water tank and ensure project sustainability through economic analysis. Measurements indicate that Yeh Ha spring has a flow rate of 0.201 m3/s with a head of 4.6 m. Based on this, a crossflow turbine equipped with a centrifugal pump and variable frequency drive is chosen to meet the water needs of 12,277 people or 2,455 families. The investment for the PLTMH and water pump system is Rp3,191,330,505 with a project's economic life of 30 years. Feasibility analysis shows that the design is viable, with a positive net present value of Rp1,534,531,357 and Rp930,180,420 at discount rates of 10% and 12%, respectively. However, the benefit-cost ratio (BCR) is less than 1, at 0.48 and 0.29. The internal rate of return (IRR) is 17.6% and 15.5%, with a break-even point of 2,699,253 m3 sold, requiring a payback period of 9 years at a 10% discount rate and 10 years and 4 months at a 12% discount rate.

Simulasi Turbin Portabel Jenis Cross Flow Untuk Pembangkit Listrik Tenaga Pikohidro (PLTPH)

In Indonesia, especially West Java Province, there are quite a lot of rivers with quite high or mountainous elevation differences, generally, these rivers are used as tourist attractions which are located far from residential areas. To meet electricity needs, an alternative is to convert the river flow into electricity, either used for lighting or simply to charge electronic devices such as gadgets. One solution is to make small turbines that can be moved and can be produced in large quantities. Through this activity, a simulation analysis will be carried out on previously available designs so that existing weaknesses can be seen so that they can become evaluation material for subsequent designs. The stages of activities carried out include the study stage of simulations using CFD to determine deficiencies in inflow performance and also serve as material for the evaluation of subsequent designs. From the results of the simulation that has been carried out, the flow in the existing equipment has a decrease when it hits the cross-flow turbine blade so that the flow is not at its optimal speed, besides that the kinetic energy has not been completely converted into mechanical energy which can be seen in the velocity distribution picture, namely the flow still has a speed when it enters the outlet hole, this becomes a loss for the tool and becomes a note for evaluation for further tool design.

ANALISIS PERENCANAAN PEMBANGKIT LISTRIK TENAGA MIKRO HIDRO (PLTMH) DI DESA NEGERI GUGUNG SIBOLANGIT

The Micro-Hydro Power Plant (PLTMH) is a small-scale hydropower generator with an installed capacity of less than 200 kW. It utilizes the flow of water from irrigation channels, rivers, or natural waterfalls by harnessing the available waterfall height at the construction site. This study focuses on the planning techniques and equipment required for PLTMH located in rural areas such as Negeri Gugung Sibolangit to meet the electricity needs of the residents. The research includes a technical feasibility study by surveying the hydrological potential and the potential falling height (head) at the planned PLTMH development site. Based on the calculations, the electricity demand for the residents of Negeri Gugung Sibolangit during peak load is estimated to be 20 kW. Field surveys indicate that the potential water discharge in the river of Negeri Gugung Sibolangit is approximately 0.95 m3/s, with a planned water discharge in the diversion channel of 0.38 m3/s and a waterfall height of 7.5 meters. This configuration can generate a power of 28 kW, which is sufficient to meet the needs of the local population. Considering the head, planned discharge, and installed capacity, the suitable turbine type is determined to be a cross-flow turbine, and the generator type is identified as a synchronous generator. Based on these parameters, it can be concluded that building a PLTMH in Negeri Gugung Sibolangit is highly feasible.

Evaluation of Mixing Effects and Particle Breakage on a Cross Flow Turbine with DEM

AbstractVarious effects during conveying and storage processes lead to size segregation of bulk material, but many applications require a mostly constant particle size distribution. Especially during bunker filling, segregation effects are noticed, which are further intensified by possible core flow effects. In order to reduce segregation effects during bunker filling, a cross flow turbine is installed at a bunker used for storage of blast furnace sinter. In this contribution, discrete element simulations were performed to analyze mixing effects and possible particle breakage due to the cross flow turbine. Significant mixing effects during bunker filling are noticed due to the cross flow turbine. The results show a more evenly distributed bunker outflow in terms of particle size.Particle breakage is analyzed by means of a newly developed breakage model for the Discrete Element Method (DEM). 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 automated single particle impact tester for rapid analysis of breakage characteristics of bulk materials.

Preliminary Study on Recirculation Vortex and Turbulence Inside Ultra Low Head Pico Hydro Cross-Flow Turbine using Computational Fluid Dynamics Method

Cross-flow turbines (CFT) have evolved since the first investigation in 1949. After some use of computational fluid dynamics (CFD) simulations in CFT development, it is known that there might be a recirculation vortex inside the CFT. At the CFT internal flow, some significant turbulent flow occurred, which is indicated by a higher value of turbulence kinetic energy (TKE). However, the effect of the turbulence inside this turbine still evokes many questions. This study ran Several CFD simulations on three CFT blade designs. One of them has already been tested experimentally, and the others are the modifications of the first design. There are two scenarios for the simulations: run in a traditionally two-phase condition or in a submerged state to maximize the usage of the potential head. This study found that the existing configuration has a contra-directional permanent recirculation, dead area, and high turbulency spot, which induce a higher loss. Meanwhile, all those phenomena could be minimized under the modified blade condition. The modification improves multiphase CFT performance by relatively 22.2% efficiency and 16.6% relative escalation for the submerged condition. However, the expected recirculation flow found in the prior study was still not found in this study. Another modification is still needed.

Effect of Cross-Sectional Depth on Horizontal and 30° Slop Spillway Open Channel Pico Hydro Cross-Flow Turbine Efficiency

Harvesting the kinetic energy from the small dam’s spillway downstream flow in agricultural areas is interesting. On the other hand, a cross-flow turbine (CFT) is a unique impulse turbine because it works at a higher specific speed, which means this turbine works at a lower head and higher water flow rate. Thus, there is an opportunity to use a CFT to harvest the energy in the spillway. There are two possible scenarios: at the flat horizontal and the 30° slop flow. Several computational fluid dynamics (CFD) simulations were conducted to test the hypothesis. The simulations were performed with five variations of the ratio between the cross-sectional depth parameter of the spillway’s flow before approaching the turbine for each scenario. The total head in the present study case is 3.0 meters with 120 l/s of water discharge. The simulations used ANSYS® Fluent™ for 2D CFD simulation. The tests found that the CFT could attain 80.36% efficiency. Moreover, some water flows over the turbine at a higher rotational speed, leading to a significant loss in turbine performance, called potential loss. This finding indicates that the CFT could harvest the spillway’s flow kinetic energy when the flow is not too deep.

Validation and Assessment of a Hybrid VOF-Lagrangian Numerical Methodology for Turbulent Liquid Fuel Jets in High-Speed Crossflow

Abstract For gas turbine combustors, injecting liquid fuel in crossflow can achieve superior mixing characteristics to improve performance and reduce emissions. Robust numerical design tools are needed to accelerate the development of low-emissions technologies. Atomization modeling is often facilitated by using the Lagrangian approach rather than the more complex and computationally expensive Volume-of-Fluid (VOF) approach. However, most Lagrangian breakup models rely on empirical constants that must be fully calibrated for jets in crossflow and representative conditions. A hybrid approach could deliver a better compromise between accuracy and computational cost. This study proposes and validates a novel numerical methodology for coupling the VOF and Lagrangian approaches using a stochastic breakup model with Adaptive Mesh Refinements for turbulent liquid fuel jets in crossflow under more representative gas turbine conditions. The predictions were validated in the near and far-field regions using datasets at high pressures (1–8 bar), Weber numbers (720–1172), and momentum flux ratios (6–33). The predictive capabilities and computational cost were also compared to the Lagrangian approach coupled with large eddy simulations (LES) and with the unsteady Reynolds-Averaged Navier–Stokes (RANS) methodology previously developed and validated by the authors. The effect of different VOF-Lagrangian transition criteria on the computational cost was also assessed and recommendations were provided for further improvements. The overall LES predictions were significantly improved by the proposed hybrid methodology. Although it tends to underpredict the spray trajectory and Sauter Mean Diameter compared to the URANS methodology, it better captures the diameter in the wake region and the droplet velocities.

Comparison of Crossflow Turbine Performance through Nozzle Position Variations Using ANSYS Simulation

The performance comparison of Crossflow turbines is greatly influenced by the position of the nozzle in the conversion of water energy into mechanical energy that occurs through the blades, runners, and shafts of Crossflow turbines. The study aims to directly examine the visualization of water fluid dynamics across the turbine runner blade and enhance the performance of the Crossflow turbine by varying the nozzle position. This study intends to investigate the impact of water flow dynamics and emission on the performance of Crossflow turbines with a combined horizontal-vertical nozzle position, specifically focusing on the magnitude of the number of turbine blades driven and the size of the runner blade area. The objective of investigating nozzle position variations in Crossflow turbines is to determine the specific nozzle position at which the turbine blade may efficiently extract maximum energy from the water flow, hence optimizing turbine performance. The research method using models made using CAD software is AutoCAD by exporting to IGES or IGS format to be compatible with ANSYS. The simulation of this research is with post-processing. There are three, namely making animations, making contours, and taking data to compare cross-turbine performance using variations in nozzle position. Crossflow turbine performance with horizontal nozzle position torque and turbine power is lower, and there is an increase in a vertical position. Then, the horizontal and vertical nozzle position is very good because the nozzle is more effective with maximum turbine performance, namely 13.811-watt turbine power 1,099 turbine torque at 120 rpm.