Large-Scale Additive Manufacturing for Low Cost Small-Scale Wind Turbine Manufacturing

New large-scale laboratory data are presented on a physical model of a spar buoy wind turbine with angular motion of control surfaces implemented (pitch control). The peculiarity of this type of rotating blade represents an essential aspect when studying floating offshore wind structures. Experiments were designed specifically to compare different operational environmental conditions in terms of wave steepness and wind speed. Results discussed here were derived from an analysis of only a part of the whole dataset. Consistent with recent small-scale experiments, data clearly show that the waves contributed to most of the model motions and mooring loads. A significant nonlinear behavior for sway, roll and yaw has been detected, whereas an increase in the wave period makes the wind speed less influential for surge, heave and pitch. In general, as the steepness increases, the oscillations decrease. However, higher wind speed does not mean greater platform motions. Data also indicate a significant role of the blade rotation in the turbine thrust, nacelle dynamic forces and power in six degrees of freedom. Certain pairs of wind speed-wave steepness are particularly unfavorable, since the first harmonic of the rotor (coupled to the first wave harmonic) causes the thrust force to be larger than that in more energetic sea states. The experiments suggest that the inclusion of pitch-controlled, variable-speed blades in physical (and numerical) tests on such types of structures is crucial, highlighting the importance of pitch motion as an important design factor.

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1-D Model Analysis of Tesla Turbine for Small Scale Organic Rankine Cycle (ORC) System

Volume 3: Coal, Biomass and Alternative Fuels; Cycle Innovations; Electric Power; Industrial and Cogeneration Applications; Organic Rankine Cycle Power Systems ◽

10.1115/gt2017-63797 ◽

2017 ◽

Author(s):

Jian Song ◽

Chun-wei Gu

Keyword(s):

Large Scale ◽

Low Cost ◽

Organic Rankine Cycle ◽

Axial Flow ◽

Rankine Cycle ◽

Expansion Ratio ◽

Working Fluid ◽

Small Scale ◽

Low Grade ◽

D Model

Energy shortage and environmental deterioration are two crucial issues that the developing world has to face. In order to solve these problems, conversion of low grade energy is attracting broad attention. Among all of the existing technologies, Organic Rankine Cycle (ORC) has been proven to be one of the most effective methods for the utilization of low grade heat sources. Turbine is a key component in ORC system and it plays an important role in system performance. Traditional turbine expanders, the axial flow turbine and the radial inflow turbine are typically selected in large scale ORC systems. However, in small and micro scale systems, traditional turbine expanders are not suitable due to large flow loss and high rotation speed. In this case, Tesla turbine allows a low-cost and reliable design for the organic expander that could be an attractive option for small scale ORC systems. A 1-D model of Tesla turbine is presented in this paper, which mainly focuses on the flow characteristics and the momentum transfer. This study improves the 1-D model, taking the nozzle limit expansion ratio into consideration, which is related to the installation angle of the nozzle and the specific heat ratio of the working fluid. The improved model is used to analyze Tesla turbine performance and predict turbine efficiency. Thermodynamic analysis is conducted for a small scale ORC system. The simulation results reveal that the ORC system can generate a considerable net power output. Therefore, Tesla turbine can be regarded as a potential choice to be applied in small scale ORC systems.

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Variational data assimilation with superparameterization

Nonlinear Processes in Geophysics Discussions ◽

10.5194/npgd-2-513-2015 ◽

2015 ◽

Vol 2 (2) ◽

pp. 513-536 ◽

Cited By ~ 1

Author(s):

I. Grooms ◽

Y. Lee

Keyword(s):

Data Assimilation ◽

Large Scale ◽

Climate Models ◽

Low Cost ◽

Ocean Model ◽

Variational Data Assimilation ◽

Scale Model ◽

Small Scale ◽

New Applications ◽

Lorenz 96

Abstract. Superparameterization (SP) is a multiscale computational approach wherein a large scale atmosphere or ocean model is coupled to an array of simulations of small scale dynamics on periodic domains embedded into the computational grid of the large scale model. SP has been successfully developed in global atmosphere and climate models, and is a promising approach for new applications. The authors develop a 3D-Var variational data assimilation framework for use with SP; the relatively low cost and simplicity of 3D-Var in comparison with ensemble approaches makes it a natural fit for relatively expensive multiscale SP models. To demonstrate the assimilation framework in a simple model, the authors develop a new system of ordinary differential equations similar to the two-scale Lorenz-'96 model. The system has one set of variables denoted {Yi}, with large and small scale parts, and the SP approximation to the system is straightforward. With the new assimilation framework the SP model approximates the large scale dynamics of the true system accurately.

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Low-cost Large Scale Vermicompost Unit

Journal of Physics Conference Series ◽

10.1088/1742-6596/2115/1/012026 ◽

2021 ◽

Vol 2115 (1) ◽

pp. 012026

Author(s):

Sonam Solanki ◽

Gunendra Mahore

Keyword(s):

Large Scale ◽

Low Cost ◽

Small Scale ◽

Scale Production ◽

Key Innovation ◽

Main Challenge ◽

Long Run ◽

Large Scale Production ◽

Term Maintenance

Abstract In the current process of producing vermicompost on a large-scale, the main challenge is to keep the worms alive. This is achieved by maintaining temperature and moisture in their living medium. It is a difficult task to maintain these parameters throughout the process. Currently, this is achieved by building infrastructure but this method requires a large initial investment and long-run maintenance. Also, these methods are limited to small-scale production. For large-scale production, a unit is developed which utilises natural airflow with water and automation. The main aim of this unit is to provide favourable conditions to worms in large-scale production with very low investment and minimum maintenance in long term. The key innovation of this research is that the technology used in the unit should be practical and easy to adopt by small farmers. For long-term maintenance of the technology lesser number of parts are used.

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Investigation of performance of small wind turbine blades with winglets

International Journal of Numerical Methods for Heat &amp Fluid Flow ◽

10.1108/hff-09-2019-0695 ◽

2020 ◽

Vol ahead-of-print (ahead-of-print) ◽

Cited By ~ 2

Author(s):

Michal Kulak ◽

Michal Lipian ◽

Karol Zawadzki

Keyword(s):

Wind Turbine ◽

Low Cost ◽

Turbine Blades ◽

Significant Degree ◽

Small Scale ◽

Performance Study ◽

Wind Turbine Blades ◽

Content Type ◽

Efficiency Increase ◽

Energy Prosumers

Purpose This paper aims to discuss the results of the performance study of wind turbine blades equipped with winglets. An investigation focusses on small wind turbines (SWTs), where the winglets are recalled as one of the most promising concepts in terms of turbine efficiency increase. Design/methodology/approach To investigate a contribution of winglets to SWT aerodynamic efficiency, a wind tunnel experiment was performed at Lodz University of Technology. In parallel, computational fluid dynamics (CFD) simulations campaign was conducted with the ANSYS CFX software to investigate appearing flow structures in greater detail. Findings The research indicates the potential behind the application of winglets in low Reynolds flow conditions, while the CFD study enables the identification of crucial regions influencing the flow structure in the most significant degree. Research limitations/implications As the global effect on a whole rotor is a result of a small-scale geometrical feature, it is important to localise unveiled phenomena and the mechanisms behind their generation. Practical implications Even the slightest efficiency improvement in a distributed generation installation can promote such a solution amongst energy prosumers and increase their independence from limited natural resources. Originality/value The winglet-equipped blades of SWTs provide an opportunity to increase the device performance with relatively low cost and ease of implementation.

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Powder-Binder Jetting Large-Scale, Metal Direct-Drive Generators: Selecting the Powder, Binder, and Process Parameters

ASME 2019 Power Conference ◽

10.1115/power2019-1853 ◽

2019 ◽

Author(s):

Austin C. Hayes ◽

Gregory L. Whiting

Keyword(s):

Additive Manufacturing ◽

Wind Turbine ◽

Large Scale ◽

Material Selection ◽

Direct Drive ◽

Turbine Generators ◽

Wind Turbine Generators ◽

Complex Parts ◽

Printing Parameters ◽

Binder Jetting

Abstract Additive manufacturing enables the production of complex geometries extremely difficult to create with conventional subtractive methods. While good at producing complex parts, its limitations can be seen through its penetration into everyday manufacturing markets. Throughput limitations, poor surface roughness, limited material selection, and repeatability concerns hinder additive manufacturing from revolutionizing all but the low-volume, high-value markets. This work characterizes combining powder-binder jetting with traditional casting techniques to create large, complex metal parts. Specifically, we extend this technology to wind turbine generators and provide initial feasibility of producing complex direct-drive generator rotor and stator designs. In this process, thermal inkjet printer heads selectively deposit binder on hydroperm casting powder. This powder is selectively solidified and baked to remove moisture before being cast through traditional methods. This work identifies a scalable manufacturing process to print large-scale wind turbine direct drive generators. As direct-drive generators are substantially larger than their synchronous counterparts, a printing process must be able to be scaled for a 2–5 MW 2–6m machine. For this study, research on the powder, binder, and printing parameters is conducted and evaluated for scalability.

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Gloxinia—An Open-Source Sensing Platform to Monitor the Dynamic Responses of Plants

Sensors ◽

10.3390/s20113055 ◽

2020 ◽

Vol 20 (11) ◽

pp. 3055

Author(s):

Olivier Pieters ◽

Tom De Swaef ◽

Peter Lootens ◽

Michiel Stock ◽

Isabel Roldán-Ruiz ◽

...

Keyword(s):

Open Source ◽

Large Scale ◽

Environmental Changes ◽

Low Cost ◽

Current Data ◽

Dynamic Responses ◽

Small Scale ◽

Data Logging ◽

Short Term ◽

Sensing Platforms

The study of the dynamic responses of plants to short-term environmental changes is becoming increasingly important in basic plant science, phenotyping, breeding, crop management, and modelling. These short-term variations are crucial in plant adaptation to new environments and, consequently, in plant fitness and productivity. Scalable, versatile, accurate, and low-cost data-logging solutions are necessary to advance these fields and complement existing sensing platforms such as high-throughput phenotyping. However, current data logging and sensing platforms do not meet the requirements to monitor these responses. Therefore, a new modular data logging platform was designed, named Gloxinia. Different sensor boards are interconnected depending upon the needs, with the potential to scale to hundreds of sensors in a distributed sensor system. To demonstrate the architecture, two sensor boards were designed—one for single-ended measurements and one for lock-in amplifier based measurements, named Sylvatica and Planalta, respectively. To evaluate the performance of the system in small setups, a small-scale trial was conducted in a growth chamber. Expected plant dynamics were successfully captured, indicating proper operation of the system. Though a large scale trial was not performed, we expect the system to scale very well to larger setups. Additionally, the platform is open-source, enabling other users to easily build upon our work and perform application-specific optimisations.

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A highly flexible laboratory setup to demonstrate granular flow characteristics

Natural Hazards ◽

10.1007/s11069-020-04234-y ◽

2020 ◽

Vol 104 (2) ◽

pp. 1581-1596

Author(s):

Thomas Heinze

Keyword(s):

Granular Flow ◽

Large Scale ◽

Numerical Models ◽

Low Cost ◽

Experimental Investigations ◽

Small Scale ◽

Local Pressure ◽

Slope Length ◽

Runout Distance ◽

Laboratory Setup

Abstract Dynamics of snow avalanches or landslides can be described by rapid granular flow. Experimental investigations of granular flow at laboratory scale are often required to analyze flow behaviour and to develop adequate mathematical and numerical models. Most investigations use image-based analysis, and additional sensors such as pressure gauges are not always possible. Testing various scenarios and parameter variations such as different obstacle shapes and positions as well as basal topography and friction usually requires either the construction of a new laboratory setups for each test or a cumbersome reconstruction. In this work, a highly flexible and modular laboratory setup is presented based on LEGO bricks. The flexibility of the model is demonstrated, and possible extensions for future laboratory tests are outlined. The setup is able to reproduce published laboratory experiments addressing current scientific research topics, such as overflow of a rigid reflector, flow on a bumpy surface and against a rigid wall using standard image-based analysis. This makes the setup applicable for quick scenario testing, e.g. for hypothesis testing or for low-cost testing prior to large-scale experiments, and it can contribute to the validation of external results and to benchmarks of numerical models. Small-scale laboratory setups are also very useful for demonstration purposes such as education and public outreach, both crucial in the context of natural hazards. The presented setup enables variation of parameters such as of slope length, channel width, height and shape, inclination, bed friction, obstacle position and shape, as well as density, composition, amount and grain size of flowing mass. Observable quantities are flow type, flow height, flow path and flow velocity, as well as runout distance, size and shape of the deposited material. Additional sensors allow further quantitative assessments, such as local pressure values.

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Community Monitoring Improves Public Service Provision at Scale: Experimental Evidence from a Child Development Program in Nicaragua

10.18235/0002869 ◽

2020 ◽

Author(s):

Florencia López Boo ◽

Jane Leer ◽

Akito Kamei

Keyword(s):

Child Development ◽

Experimental Evidence ◽

Large Scale ◽

Service Providers ◽

Low Cost ◽

Development Program ◽

Small Scale ◽

Community Monitoring ◽

Quality Assurance Mechanism ◽

Intent To Treat

Expanding small-scale interventions without lowering quality and attenuating impact is a critical policy challenge. Community monitoring overs a low-cost quality assurance mechanism by making service providers account-able to local citizens, rather than distant administrators. This paper provides experimental evidence from a home visit parenting program implemented at scale by the Nicaraguan government, with two types of monitoring: (a) institutional monitoring; and (b) community monitoring. We find d a positive intent-to-treat effect on child development, but only among groups randomly assigned to community monitoring. Our findings show promise for the use of community monitoring to ensure quality in large-scale government-run social programs.

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