The platform for open and practice-oriented research

Products 804

product

Socio-psychological effects of wind turbine noise

This paper presents a report of some of the activities of the International Energy Agency's (IEA) Wind TCP Task 39. By identifying best practices in an international collaboration, Task 39 hopes to provide the scientific evidence to inform improved regulations and standards, increasing the effectiveness of quiet wind turbine technology. Task 39 is divided into five separate work packages, which address the broad wind turbine noise topic in successive steps; from wind turbine noise generation (WP2), to airborne noise propagation over large distances (WP3). The assessment of wind turbine noise and its impact on humans is addressed in WP4, while WP5 is dealing with other aspects of perception and acceptance, which may be related to noise. All WPs contribute to a dedicated Work Package on dissemination (WP1). This paper provides an update of activities primarily associated with the socio-psychological aspects of wind turbine noise (WP4 and WP5). Through the consideration of a wide variety of factors, including measurement technologies, auralisation and psychology, the effects on noise perception, annoyance and its impact on wellbeing and health is being further investigated. This paper presents a discussion of the activities of each member country and highlights some of the key research questions that need to be further considered.

LINK

product

Wind resource characteristics and energy yield for micro wind turbines integrated on noise barriers

This paper assesses wind resource characteristics and energy yield for micro wind turbines integrated on noise barriers. An experimental set-up with sonic anemometers placed on top of the barrier in reference positions is realized. The effect on wind speed magnitude, inflow angle and turbulence intensity is analysed. The annual energy yield of a micro wind turbine is estimated and compared using data from a micro-wind turbine wind tunnel experiment and field data. Electrical energy costs are discussed as well as structural integration cost reduction and the potential energy yield could decrease costs. It was found that instantaneous wind direction towards the barrier and the height of observation play an influential role for the results. Wind speed increases in perpendicular flows while decreases in parallel flow, by +35% down to −20% from the reference. The azimuth of the noise barrier expressed in wind field rotation angles was found to be influential resulted in 50%–130% changes with respect to annual energy yield. A micro wind turbine (0.375 kW) would produce between 100 and 600 kWh annually. Finally, cost analysis with cost reductions due to integration and the energy yield changes due to the barrier, show a LCOE reduction at 60%–90% of the reference value. https://doi.org/10.1016/j.jweia.2020.104206

PDF

product

Performance characteristics of a micro wind turbine integrated on a noise barrier

tract Micro wind turbines can be structurally integrated on top of the solid base of noise barriers near highways. A number of performance factors were assessed with holistic experiments in wind tunnel and in the field. The wind turbines underperformed when exposed in yawed flow conditions. The theoretical cosθ theories for yaw misalignment did not always predict power correctly. Inverter losses turned out to be crucial especially in standby mode. Combination of standby losses with yawed flow losses and low wind speed regime may even result in a net power consuming turbine. The micro wind turbine control system for maintaining optimal power production underperformed in the field when comparing tip speed ratios and performance coefficients with the values recorded in the wind tunnel. The turbine was idling between 20%–30% of time as it was assessed for sites with annual average wind speeds of three to five meters per second without any power production. Finally, the field test analysis showed that inadequate yaw response could potentially lead to 18% of the losses, the inverter related losses to 8%, and control related losses to 33%. The totalized loss led to a 48% efficiency drop when compared with the ideal power production measured before the inverter. Micro wind turbine’s performance has room for optimization for application in turbulent wind conditions on top of noise barriers. https://doi.org/10.3390/en14051288

PDF

Performance characteristics of a micro wind turbine integrated on a noise barrier

People 2

person

Gerard Schepers

Professor

person

Marcel Wierckx

Projects 9

project

Consultant on Aircraft CO2 standard

Since March 2013, Paul Peeters is a member of the ICAO/CAEP Working Group 3, which is responsible for setting a new fuel efficiency standard for of civil aviation. He does so for the International Coalition for Sustainable Aviation (ICSA). ICSA was established in 1998 by a group of national and international environmental NGOs as official observers. Since its inception, ICSA has contributed to CAEP’s work on technical means to reduce emissions and noise, the role of market-based measures, supporting economic and environmental analysis, modelling and forecasting, and ICAO’s carbon calculator. It has also been invited to present its views at ICAO workshops on carbon markets and bio-fuels, and has presented to the high-level Group on Internation Aviation and Climate Change (GIACC). ICSA uses the expertise within its NGO membership to formulate its co-ordinated positions. To gain the broadest level of understanding and input from environmental NGOs, ICSA communicates with, and invites comment from, other NGO networks and bodies working in related areas. ICSA’s participation in ICAO and CAEP meetings is currently provided by the Aviation Environment Federation (AEF), the International Council for Clean Transportation (ICCT) and Transport and Environment (T&E). See http://www.icsa-aviation.org

Finished

project

een Twents Onderzoek naar Extreem Laaggeluidsproducerende drones (OEL)

Despite their various appealing features, drones also have some undesirable side-effects. One of them is the psychoacoustic effect that originates from their buzzing noise that causes significant noise pollutions. This has an effect on nature (animals run away) and on humans (noise nuisance and thus stress and health problems). In addition, these buzzing noises contribute to alerting criminals when low-flying drones are deployed for safety and security applications. Therefore, there is an urgent demand from SMEs for practical knowledge and technologies that make existing drones silent, which is the main focus of this project. This project contributes directly to the KET Digital Innovations\Robotics and multiple themes of the top sectors: Agriculture, Water and Food, Health & Care and Safety. The main objective of this project is: Investigate the desirability and possibilities of extremely silent drone technologies for agriculture, public space and safety This is an innovative project and there exist no such drone technology that attempts to reduce the noises coming from drones. The knowledge within this project will be converted into the first proof-of-concepts that makes the technology the first Minimum Viable Product suitable for market evaluations. The partners of this project include WhisperUAV, which has designed the first concept of a silent drone. As a fiber-reinforced 3D composite component printer, Fiberneering plays a crucial role in the (further) development of silent drone technologies into testable prototypes. Sorama is involved as an expert company in the context of mapping the sound fields in and around drones. The University of Twente is involved as a consultant and co-developer, and Research group of mechatronics at Saxion is involved as concept developer, system and user requirement verifier and validator. As an unmanned systems innovation cluster, Space53 will be involved as innovation and networking consultant.

Finished

project

MRI Proof Sensors suitable for Catheterization (MPSC)

MSEs have encountered limitations while pushing the limits of catheter tip sensors performance. The limitations summarized: - sensors are not immune to electrical signal noise, cross talk, and EM fields; - sensors are not immune to high magnetic fields, i.e. not suitable for MR imaging; - extending the amount of sensors on the catheter tip is limited due to cluttering of wires. A fundamentally different approach using integrated optics is chosen for developing a new generation catheter sensors. The complexity of the design and production problems represents a knowledge gap, that can be bridged in the proposed consortium. This project consists of four work packages, total duration two years, subdivided into four phases. A crucial deliverable of the project is presented at the end of phase IV (WP4), namely a demonstrator integrating pressure and temperature sensors (obtained from WP1) with a newly designed readout system. This system is modularly extendable for future catheter tip sensors. In WP1, pressure- and temperature sensors are developed using two design approaches. In WP2 the influence of downscaling an ultrasound MZI device is explored and the microfabrication process parameters are studied. An additional goal of WP2 is to find the most suitable method for measuring lactate concentration. Among the deliverables five manuscripts: manuscript 1 includes simulations and measurements of the developed pressure and temperature sensors, manuscript 2 answers the question: can a grated fiber be used for measuring pressure and temperature on a tip? Manuscript 3 answers the question: which method is most suitable for measuring lactate concentration on a tip? Manuscript 4 answers the question: does a US intensity detector fit on a catheter tip while obeying the LoR? Manuscript 5 describes the performance of the demonstrator (Phase IV), i.e. integration of T/P sensing with a modular read out system.

Finished

project

Ph.D.-project 'Examining in-class activities to facilitate academic achievement in higher education: a framework for optimal indoor environmental conditions'

Examining in-class activities to facilitate academic achievement in higher educationThere is an increasing interest in how to create an effective and comfortable indoor environment for lecturers and students in higher education. To achieve evidence-based improvements in the indoor environmental quality (IEQ) of higher education learning environments, this research aimed to gain new knowledge for creating optimal indoor environmental conditions that best facilitate in-class activities, i.e. teaching and learning, and foster academic achievement. The academic performance of lecturers and students is subdivided into short-term academic performance, for example, during a lecture and long-term academic performance, during an academic course or year, for example. First, a systematic literature review was conducted to reveal the effect of indoor environmental quality in classrooms in higher education on the quality of teaching, the quality of learning, and students’ academic achievement. With the information gathered on the applied methods during the literature review, a systematic approach was developed and validated to capture the effect of the IEQ on the main outcomes. This approach enables research that aims to examine the effect of all four IEQ parameters, indoor air quality, thermal conditions, lighting conditions, and acoustic conditions on students’ perceptions, responses, and short-term academic performance in the context of higher education classrooms. Next, a field experiment was conducted, applying the validated systematic approach, to explore the effect of multiple indoor environmental parameters on students and their short-term academic performance in higher education. Finally, a qualitative case study gathered lecturers’ and students’ perceptions related to the IEQ. Furthermore, how these users interact with the environment to maintain an acceptable IEQ was studied.During the systematic literature review, multiple scientific databases were searched to identify relevant scientific evidence. After the screening process, 21 publications were included. The collected evidence showed that IEQ can contribute positively to students’ academic achievement. However, it can also affect the performance of students negatively, even if the IEQ meets current standards for classrooms’ IEQ conditions. Not one optimal IEQ was identified after studying the evidence. Indoor environmental conditions in which students perform at their best differ and are task depended, indicating that classrooms should facilitate multiple indoor environmental conditions. Furthermore, the evidence provides practical information for improving the design of experimental studies, helps researchers in identifying relevant parameters, and lists methods to examine the influence of the IEQ on users.The measurement methods deduced from the included studies of the literature review, were used for the development of a systematic approach measuring classroom IEQ and students’ perceived IEQ, internal responses, and short-term academic performance. This approach allowed studying the effect of multiple IEQ parameters simultaneously and was tested in a pilot study during a regular academic course. The perceptions, internal responses, and short-term academic performance of participating students were measured. The results show associations between natural variations of the IEQ and students’ perceptions. These perceptions were associated with their physiological and cognitive responses. Furthermore, students’ perceived cognitive responses were associated with their short-term academic performance. These observed associations confirm the construct validity of the composed systematic approach. This systematic approach was then applied in a field experiment, to explore the effect of multiple indoor environmental parameters on students and their short-term academic performance in higher education. A field study, with a between-groups experimental design, was conducted during a regular academic course in 2020-2021 to analyze the effect of different acoustic, lighting, and indoor air quality (IAQ) conditions. First, the reverberation time was manipulated to 0.4 s in the intervention condition (control condition 0.6 s). Second, the horizontal illuminance level was raised from 500 to 750 lx in the intervention condition (control condition 500 lx). These conditions correspond with quality class A (intervention condition) and B (control condition), specified in Dutch IEQ guidelines for school buildings (2015). Third, the IAQ, which was ~1100 ppm carbon dioxide (CO2), as a proxy for IAQ, was improved to CO2 concentrations under 800 ppm, meeting quality class A in both conditions. Students’ perceptions were measured during seven campaigns with a questionnaire; their actual cognitive and short-term academic performances were evaluated with validated tests and an academic test, composed by the lecturer, as a subject-matter-expert on the taught topic, covered subjects discussed during the lecture. From 201 students 527 responses were collected and analyzed. A reduced RT in combination with raised HI improved students’ perceptions of the lighting environment, internal responses, and quality of learning. However, this experimental condition negatively influenced students’ ability to solve problems, while students' content-related test scores were not influenced. This shows that although quality class A conditions for RT and HI improved students’ perceptions, it did not influence their short-term academic performance. Furthermore, the benefits of reduced RT in combination with raised HI were not observed in improved IAQ conditions. Whether the sequential order of the experimental conditions is relevant in inducing these effects and/or whether improving two parameters is already beneficial, is unknownFinally, a qualitative case study explored lecturers’ and students’ perceptions of the IEQ of classrooms, which are suitable to give tutorials with a maximum capacity of about 30 students. Furthermore, how lecturers and students interact with this indoor environment to maintain an acceptable IEQ was examined. Eleven lecturers of the Hanze University of Applied Sciences (UAS), located in the northern part of the Netherlands, and twenty-four of its students participated in three focus group discussions. The findings show that lecturers and students experience poor thermal, lighting, acoustic, and IAQ conditions which may influence teaching and learning performance. Furthermore, maintaining acceptable thermal and IAQ conditions was difficult for lecturers as opening windows or doors caused noise disturbances. In uncomfortable conditions, lecturers may decide to pause earlier or shorten a lecture. When students experienced discomfort, it may affect their ability to concentrate, their emotional status, and their quality of learning. Acceptable air and thermal conditions in classrooms will mitigate the need to open windows and doors. This allows lecturers to keep doors and windows closed, combining better classroom conditions with neither noise disturbances nor related distractions. Designers and engineers should take these end users’ perceptions into account, often monitored by facility management (FM), during the renovation or construction of university buildings to achieve optimal IEQ conditions in higher education classrooms.The results of these four studies indicate that there is not a one-size fits all indoor environmental quality to facilitate optimal in-class activities. Classrooms’ thermal environment should be effectively controlled with the option of a local (manual) intervention. Classrooms’ lighting conditions should also be adjustable, both in light color and light intensity. This enables lecturers to adjust the indoor environment to facilitate in-class activities optimally. Lecturers must be informed by the building operator, for example, professionals of the Facility Department, how to change classrooms’ IEQ settings. And this may differ per classroom because each building, in which the classroom is located, is operated differently apart from the classroom location in the building, exposure to the environment, and its use. The knowledge that has come available from this study, shows that optimal indoor environmental conditions can positively influence lecturers’ and students’ comfort, health, emotional balance, and performance. These outcomes have the capacity to contribute to an improved school climate and thus academic achievement.

Finished

project

Physics-based acoustic monitoring for innovative fault diagnosis in rotating machinery

Rotating machinery, such as centrifugal pumps, turbines, bearings, and other critical systems, is the backbone of various industrial processes. Their failures can lead to significant maintenance costs and downtime. To ensure their continuous operation, we propose a fault diagnosis and monitoring framework that leverages the innovative use of acoustic sensors for early fault detection, especially in components less accessible for traditional vibration-based monitoring strategies. The main objective of the proposed project is to develop a fault diagnosis and monitoring framework for rotating machinery, including the fusion of acoustic sensors and physics-based models. By combining real-time monitoring data from acoustic sensors with an understanding of first principles, the framework will enable maintenance practitioners to identify and categorize different failure modes such as wear, fatigue, cavitation, reduced flow, bearing damage, impeller damage, misalignment, etc. In the initial phase, the focus will be on centrifugal pumps using the existing test set-up at the University of Twente. Sorama specializes in acoustic sensors to locate noise sources and will provide acoustic cameras to capture sound patterns related to pump deterioration during various operating conditions. These acoustic signals will then be correlated with the different failure modes and mechanisms that will be described by physics-based models, such as wear, fatigue, cavitation, corrosion, etc. Furthermore, a recently published data set by the Dynamics Based Maintenance research group that includes vibration analysis data and motor current analysis data of various fault scenarios, such as mentioned above, will be used as validation. The anticipated outcome of this project is a versatile framework for a physics-informed acoustic monitoring system. This system is designed to enhance early fault detection significantly, reducing maintenance costs and downtime across a broad spectrum of industrial applications, from centrifugal pumps to turbines, bearings, and beyond.

To be started

Products 804

product

Socio-psychological effects of wind turbine noise

LINK

product

Wind resource characteristics and energy yield for micro wind turbines integrated on noise barriers

PDF

product

Performance characteristics of a micro wind turbine integrated on a noise barrier

PDF