1) The document presents experimental and computational fluid dynamics (CFD) analysis of an absorptive muffler used on a wet and dry type vacuum cleaner exhaust to reduce noise levels.
2) Noise measurements showed the exhaust was a main noise source, emitting 88.2 dB. A muffler containing porous foam reduced noise by 1.1 dB.
3) CFD analysis predicted a pressure drop of 428.11 Pa without foam and 985.71 Pa with foam, corresponding to muffler backpressure.
4) Standard tests found the muffler reduced vacuum cleaner efficiency by 1.645% and air watt by 16.603W due to increased backpressure, demonstrating the muffler effectively attenuated
Odour Regulation-Solution to control Odour from Municipal Solid Waste Managem...Karthik Kumar
India is a fast growing developing country consisting of large city population in many numbers. Along with increase in population generation of waste is highly proportional. Management of these rejects in a sustainable procedure without harming the neighbours is very important. Bengaluru City generates about 4000 metric tonnes per day of MSW within the jurisdiction of Bruhat Bangalore Mahanagara Palike (BBMP), which is responsible to provide and administer the urban infrastructure and other civic amenities of the Greater Bengaluru Metropolitan area having a population of over 10 million. Handling and management of this huge quantity of municipal waste is a challenge for the urban local body (ULB) about environmental, social and techno-financial aspects.
The paper consists of proposing a method of controlling the odour produced in the solid waste treatment plant especially for the wet solid waste along with increasing the rate of composting in a conventional manner. It also included to determine the causes of malodours, to identify the most common odorants in municipal waste, properties they consist, how they can be affected and ways to prevent them to the maximum magnitude.
the method proposed in this project would be an efficient suggestion and could be implemented with ease even if it is required to change the current treatment procedure of the municipal solid waste management plants of the city. Odour emission could be regulated by avoiding the turning operation and maintaining the factors affecting composting within the permissible limits. This can be done by maintain the required temperature, moisture content by the principle of transfer of heat and aeration within the pile from the method proposed.
Design of Fire Systems in Nanjing Research Institute of Huawei’s New Rent Eng...IJRES Journal
First, building fire research status at home and abroad are introduced, the main subject of
the design of fire system in Nanjing research institute of Huawei’s new rent engineering office building. The
construction for the building is eight floors and the area of it is about 42537
2 m , the underground part is
about 1713
2 m . Its height is about 30 m . According to actual demand, with the fire regulations and
specific engineering requirements, we ensure safety by comparing with regulations and drawing
the conclusion. In the design, we check the pipeline strength of water. In the fire hydrant system, the pressure
of the most unfavorable hydrant should be calculated and check.
NEW TECHNOLOGIES USED IN AUTOMOTIVE EXHAUST SYSTEMS, REVIEWIAEME Publication
The exhaust system is an integral part of an automobile. Components such as Exhaust Manifolds, Connector pipes, X, Y, H Pipes, Oxygen Sensors, Resonators, Catalytic Convertors, Selective Catalytic Reduction and Diesel Particulate Filter techniques have evolved greatly. With
increasingly stringent emission reforms being passed by governments and increasingly stringent performance requirements being demanded of by customers, the importance of this system is increasing dramatically.
Odour Regulation-Solution to control Odour from Municipal Solid Waste Managem...Karthik Kumar
India is a fast growing developing country consisting of large city population in many numbers. Along with increase in population generation of waste is highly proportional. Management of these rejects in a sustainable procedure without harming the neighbours is very important. Bengaluru City generates about 4000 metric tonnes per day of MSW within the jurisdiction of Bruhat Bangalore Mahanagara Palike (BBMP), which is responsible to provide and administer the urban infrastructure and other civic amenities of the Greater Bengaluru Metropolitan area having a population of over 10 million. Handling and management of this huge quantity of municipal waste is a challenge for the urban local body (ULB) about environmental, social and techno-financial aspects.
The paper consists of proposing a method of controlling the odour produced in the solid waste treatment plant especially for the wet solid waste along with increasing the rate of composting in a conventional manner. It also included to determine the causes of malodours, to identify the most common odorants in municipal waste, properties they consist, how they can be affected and ways to prevent them to the maximum magnitude.
the method proposed in this project would be an efficient suggestion and could be implemented with ease even if it is required to change the current treatment procedure of the municipal solid waste management plants of the city. Odour emission could be regulated by avoiding the turning operation and maintaining the factors affecting composting within the permissible limits. This can be done by maintain the required temperature, moisture content by the principle of transfer of heat and aeration within the pile from the method proposed.
Design of Fire Systems in Nanjing Research Institute of Huawei’s New Rent Eng...IJRES Journal
First, building fire research status at home and abroad are introduced, the main subject of
the design of fire system in Nanjing research institute of Huawei’s new rent engineering office building. The
construction for the building is eight floors and the area of it is about 42537
2 m , the underground part is
about 1713
2 m . Its height is about 30 m . According to actual demand, with the fire regulations and
specific engineering requirements, we ensure safety by comparing with regulations and drawing
the conclusion. In the design, we check the pipeline strength of water. In the fire hydrant system, the pressure
of the most unfavorable hydrant should be calculated and check.
NEW TECHNOLOGIES USED IN AUTOMOTIVE EXHAUST SYSTEMS, REVIEWIAEME Publication
The exhaust system is an integral part of an automobile. Components such as Exhaust Manifolds, Connector pipes, X, Y, H Pipes, Oxygen Sensors, Resonators, Catalytic Convertors, Selective Catalytic Reduction and Diesel Particulate Filter techniques have evolved greatly. With
increasingly stringent emission reforms being passed by governments and increasingly stringent performance requirements being demanded of by customers, the importance of this system is increasing dramatically.
PERFORMANCE OF TRANSMISSION LOSS ON HYBRID MUFFLER BY USING ROCK WOOL AND GLA...IJAMSE Journal
Muffler is categorized in two broad manners as absorptive muffler and reactive muffler. A Muffler
(silencer) is an important noise control element for reduction of machinery exhaust noise, fan noise, and
other noise sources involving the flow of gases. Reactive mufflers which reduce noise by reflecting sound
energy back to its source, and absorption mufflers, which absorb sound due to the energy dissipated in the
sound-absorbing material. The attenuation levels of these types of muffler are dependent on the frequency
of the noise source. Investigations on absorption mufflers have indicated that these have fairly good noise
attenuation over a relatively wide frequency band. The combination of both reactive and absorptive muffler
is termed as hybrid muffler. Hybrid muffler design may be expected to provide broadband high noise
attenuation and low pressure drop. Experimental Two load setup and Wave 1-D is used to predict the
transmission loss of hybrid muffler. Hybrid muffler generally includes the number of perforated tubes,
number of perforated baffles with absorptive materials like asbestos, rock wool, bensoil, powertex &
advantex etc. Transmission loss measurement using hybrid muffler is discussed in this paper. Various
sound absorption materials that are currently used for noise reduction are used. This paper shows the
acoustic performance of packed dissipative muffler with the variation in packing density of absorptive
material. Here easy available absorptive materials glass fiber & rock wool is used with same space. This
study is performed by taking four designs to observe the transmission loss performance by applying
different absorptive materials with different packing density.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Background: In this study, the Component of normal exhaust system such as
muffler or silencer shell, perforated tube, spiral resonator design have been carried
out by SOLIDWORKS and a Finite Element Approach have presented for modeling
and analysis of muffler noise developed at different locations as well as temperature
distribution over silencer. The main objective of this study was to simulate and
investigate the performance of a general muffler by simulation and experimental
technique.
Methods: In order to minimize two-wheeler noise, testing were carried out in a
Bajaj pulsar two wheeler by redesigning a spiral resonator andperforator tube which
is capable of attenuating noise level by about 7 dBA (Decibels).
Results: The results obtained from simulation that as the distance increases from
inlet of silencer the sound pressure level decreases gradually.
Conclusions: Obtained results shows a significance decrease of sound pressure
level about 7 dBA from existing silencer to new designed silencer
Modal Analysis of Muffler of an Automobile by Experimental and Numerical Appr...paperpublications3
Abstract: A pollutant of concern to the mankind is the exhaust sound which should be about 105dB in the internal combustion engine. However this sound can be reduced sufficiently by means of a well-designed silencer. The suitable design and development will improve the sound level, but at the same time the performance of the engine should not be hampered. Muffler design is an important research area for an automotive industry because new regulations and standards for noise emission are formed. To examine the performance of any muffler, certain parameters are used. These parameters are Numerical modal analysis, Experimental modal analysis. In this project both Numerical and Experimental Modal analysis (TATA INDICA car) The experiment conducted on thickness of existing muffler body by FFT analyzer. Also numerous iterations are carried out by changing the thickness of muffler body, perforation of baffle plates. This methodology helps commercial users and OEM (Original Equipment Manufacturers) to design the silencer/muffler accordingly.
Numerical Investigation of Jet Noise Prediction in Exhaust Nozzle by Passive ...IJERA Editor
The project mainly focuses on the reduction of jet noise emission in the exhaust nozzle of TURBOFAN ENGINES. Reduction of noise in the exhaust system is done by attaching chevrons with particular parameters in the nozzle exit. Numerical investigations have been carried out on chevron nozzles to assess the importance of chevron parameters such as the number of chevrons like (chevron count), chevron penetration and the mixing characteristics of co flow jet. Chevron count is the pertinent parameter for noise reduction at low nozzle pressure ratios, whereas at high nozzle pressure ratios, chevron penetration is crucial. The results illustrate that by careful selection of chevron parameters substantial noise reduction can be achieved. The sound pressure level (SPL) can be calculated from that we determined the noise level at nozzle exit section. After assessing the chevron parameters we are going to modify the chevron shapes in order to get maximum noise reduction along with very negligible thrust loss. Modification of chevron is based on aspect of increasing the mixing of cold jet and the hot jet in order to decrease the noise emission. ANSYS-Fluent is a commercial CFD code which will be used for performing the simulation and the simulation configuration contains three different velocities (100,150,200) with two different nozzle model(plain & chevron nozzle). The simulation results are evaluated to find out nozzle noise level in the engine exhaust system.
Numerical Investigation of Jet Noise Prediction in Exhaust Nozzle by Passive ...IJERA Editor
The project mainly focuses on the reduction of jet noise emission in the exhaust nozzle of TURBOFAN ENGINES. Reduction of noise in the exhaust system is done by attaching chevrons with particular parameters in the nozzle exit. Numerical investigations have been carried out on chevron nozzles to assess the importance of chevron parameters such as the number of chevrons like (chevron count), chevron penetration and the mixing characteristics of co flow jet. Chevron count is the pertinent parameter for noise reduction at low nozzle pressure ratios, whereas at high nozzle pressure ratios, chevron penetration is crucial. The results illustrate that by careful selection of chevron parameters substantial noise reduction can be achieved. The sound pressure level (SPL) can be calculated from that we determined the noise level at nozzle exit section. After assessing the chevron parameters we are going to modify the chevron shapes in order to get maximum noise reduction along with very negligible thrust loss. Modification of chevron is based on aspect of increasing the mixing of cold jet and the hot jet in order to decrease the noise emission. ANSYS-Fluent is a commercial CFD code which will be used for performing the simulation and the simulation configuration contains three different velocities (100,150,200) with two different nozzle model(plain & chevron nozzle). The simulation results are evaluated to find out nozzle noise level in the engine exhaust system
EXTERIOR AUCOSTIC AND MODAL ANALYSIS OF MUFFLER OF AN AUTOMOBILE BY EXPERIMEN...paperpublications3
Abstract: A pollutant of concern to the mankind is the exhaust sound which should be about 105dB in the internal combustion engine. However this sound can be reduced sufficiently by means of a well-designed silencer. The suitable design and development will help to reduce the sound level, but at the same time the performance of the engine should not be hampered. Muffler design is an important research area for automotive industries because of new regulations and standards for noise emission. To examine the performance of any muffler, certain parameters are used. These parameters are Experimental modal analysis and Exterior Acoustic analysis. Hence in this paper review both Modal and Exterior acoustic analysis is carried out experimentally using FFT analyser and by numerical approach that is by finite element method. [1]
HCL suggests solutions to reduce airborne noise being emitted by vacuum cleaners. It has been seen that blowers used in vacuum cleaners are the main source of airborne noise and blade wakes are unavoidable in turbo machines.Focus of this whitepaper is to understand how to reduce sound intensity of vacuum cleaners and studying its effects on human hearing. ERS division in HCL proposes the design of a spiral enclosure for the blower in the vacuum cleaner. HCL suggests solutions to reduce airborne noise being emitted by vacuum cleaners. ERS division in HCL proposes the design of a spiral enclosure for the blower in the vacuum cleaner.
A Silencer is a part of the exhaust system of an automobile that plays a vital role. It needs to
have modes that are located away from the frequencies that the engine operates at, whether the engine be
idling or running at the maximum amount of revolutions per second. The purpose of the design project
performed was to determine which modes are very high and may affect the automobile adversely while in
operation. Research was performed prior to the test to determine which frequencies to look for modes at.
It was determined to conduct the experiment so data from 20 Hz to 20 KHz could be collected. The force
was generated by running the engine at different speed. Acceleration is measured by using FFT analyzer
by selecting the points on the Silencer were chosen, after looking at the data and determined to be under
damped. Therefore, our design study suggests increasing the mass, increase the damping, or providing a
negative stiffness to make the silencer more damped.
The purpose of this report is also to the study the harmful effects of noise caused by it on Engine.
In India, the transportation sector is growing rapidly and number of vehicles on Indian roads is increasing
at very fast rate. This has lead to overcrowded roads and noise pollution. Engine vibration is one of the
major source of noise in vehicles. So, it is necessary to study noise generated by four stroke petrol engine.
The study of noise generated by four stroke petrol engine is carried out with or without mufflers to check
the effectiveness of the muffler
As member of the Product Group "Air Filters" within the Eurovent Association, I am proud to announce that the first edition of the guidebook "Air Filters for General Ventilation" has been released.
Among all the main arguments related to air filtration, I would like to highlight the following:
1. New EN ISO 16890: an overview on filter classification according to the brand new standard
2. Maintenance: a critical and important topic for all the applications of air filters
3. Energy efficiency: because energy saving is not only money, but mainly an ethical choice
PERFORMANCE OF TRANSMISSION LOSS ON HYBRID MUFFLER BY USING ROCK WOOL AND GLA...IJAMSE Journal
Muffler is categorized in two broad manners as absorptive muffler and reactive muffler. A Muffler
(silencer) is an important noise control element for reduction of machinery exhaust noise, fan noise, and
other noise sources involving the flow of gases. Reactive mufflers which reduce noise by reflecting sound
energy back to its source, and absorption mufflers, which absorb sound due to the energy dissipated in the
sound-absorbing material. The attenuation levels of these types of muffler are dependent on the frequency
of the noise source. Investigations on absorption mufflers have indicated that these have fairly good noise
attenuation over a relatively wide frequency band. The combination of both reactive and absorptive muffler
is termed as hybrid muffler. Hybrid muffler design may be expected to provide broadband high noise
attenuation and low pressure drop. Experimental Two load setup and Wave 1-D is used to predict the
transmission loss of hybrid muffler. Hybrid muffler generally includes the number of perforated tubes,
number of perforated baffles with absorptive materials like asbestos, rock wool, bensoil, powertex &
advantex etc. Transmission loss measurement using hybrid muffler is discussed in this paper. Various
sound absorption materials that are currently used for noise reduction are used. This paper shows the
acoustic performance of packed dissipative muffler with the variation in packing density of absorptive
material. Here easy available absorptive materials glass fiber & rock wool is used with same space. This
study is performed by taking four designs to observe the transmission loss performance by applying
different absorptive materials with different packing density.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Background: In this study, the Component of normal exhaust system such as
muffler or silencer shell, perforated tube, spiral resonator design have been carried
out by SOLIDWORKS and a Finite Element Approach have presented for modeling
and analysis of muffler noise developed at different locations as well as temperature
distribution over silencer. The main objective of this study was to simulate and
investigate the performance of a general muffler by simulation and experimental
technique.
Methods: In order to minimize two-wheeler noise, testing were carried out in a
Bajaj pulsar two wheeler by redesigning a spiral resonator andperforator tube which
is capable of attenuating noise level by about 7 dBA (Decibels).
Results: The results obtained from simulation that as the distance increases from
inlet of silencer the sound pressure level decreases gradually.
Conclusions: Obtained results shows a significance decrease of sound pressure
level about 7 dBA from existing silencer to new designed silencer
Modal Analysis of Muffler of an Automobile by Experimental and Numerical Appr...paperpublications3
Abstract: A pollutant of concern to the mankind is the exhaust sound which should be about 105dB in the internal combustion engine. However this sound can be reduced sufficiently by means of a well-designed silencer. The suitable design and development will improve the sound level, but at the same time the performance of the engine should not be hampered. Muffler design is an important research area for an automotive industry because new regulations and standards for noise emission are formed. To examine the performance of any muffler, certain parameters are used. These parameters are Numerical modal analysis, Experimental modal analysis. In this project both Numerical and Experimental Modal analysis (TATA INDICA car) The experiment conducted on thickness of existing muffler body by FFT analyzer. Also numerous iterations are carried out by changing the thickness of muffler body, perforation of baffle plates. This methodology helps commercial users and OEM (Original Equipment Manufacturers) to design the silencer/muffler accordingly.
Numerical Investigation of Jet Noise Prediction in Exhaust Nozzle by Passive ...IJERA Editor
The project mainly focuses on the reduction of jet noise emission in the exhaust nozzle of TURBOFAN ENGINES. Reduction of noise in the exhaust system is done by attaching chevrons with particular parameters in the nozzle exit. Numerical investigations have been carried out on chevron nozzles to assess the importance of chevron parameters such as the number of chevrons like (chevron count), chevron penetration and the mixing characteristics of co flow jet. Chevron count is the pertinent parameter for noise reduction at low nozzle pressure ratios, whereas at high nozzle pressure ratios, chevron penetration is crucial. The results illustrate that by careful selection of chevron parameters substantial noise reduction can be achieved. The sound pressure level (SPL) can be calculated from that we determined the noise level at nozzle exit section. After assessing the chevron parameters we are going to modify the chevron shapes in order to get maximum noise reduction along with very negligible thrust loss. Modification of chevron is based on aspect of increasing the mixing of cold jet and the hot jet in order to decrease the noise emission. ANSYS-Fluent is a commercial CFD code which will be used for performing the simulation and the simulation configuration contains three different velocities (100,150,200) with two different nozzle model(plain & chevron nozzle). The simulation results are evaluated to find out nozzle noise level in the engine exhaust system.
Numerical Investigation of Jet Noise Prediction in Exhaust Nozzle by Passive ...IJERA Editor
The project mainly focuses on the reduction of jet noise emission in the exhaust nozzle of TURBOFAN ENGINES. Reduction of noise in the exhaust system is done by attaching chevrons with particular parameters in the nozzle exit. Numerical investigations have been carried out on chevron nozzles to assess the importance of chevron parameters such as the number of chevrons like (chevron count), chevron penetration and the mixing characteristics of co flow jet. Chevron count is the pertinent parameter for noise reduction at low nozzle pressure ratios, whereas at high nozzle pressure ratios, chevron penetration is crucial. The results illustrate that by careful selection of chevron parameters substantial noise reduction can be achieved. The sound pressure level (SPL) can be calculated from that we determined the noise level at nozzle exit section. After assessing the chevron parameters we are going to modify the chevron shapes in order to get maximum noise reduction along with very negligible thrust loss. Modification of chevron is based on aspect of increasing the mixing of cold jet and the hot jet in order to decrease the noise emission. ANSYS-Fluent is a commercial CFD code which will be used for performing the simulation and the simulation configuration contains three different velocities (100,150,200) with two different nozzle model(plain & chevron nozzle). The simulation results are evaluated to find out nozzle noise level in the engine exhaust system
EXTERIOR AUCOSTIC AND MODAL ANALYSIS OF MUFFLER OF AN AUTOMOBILE BY EXPERIMEN...paperpublications3
Abstract: A pollutant of concern to the mankind is the exhaust sound which should be about 105dB in the internal combustion engine. However this sound can be reduced sufficiently by means of a well-designed silencer. The suitable design and development will help to reduce the sound level, but at the same time the performance of the engine should not be hampered. Muffler design is an important research area for automotive industries because of new regulations and standards for noise emission. To examine the performance of any muffler, certain parameters are used. These parameters are Experimental modal analysis and Exterior Acoustic analysis. Hence in this paper review both Modal and Exterior acoustic analysis is carried out experimentally using FFT analyser and by numerical approach that is by finite element method. [1]
HCL suggests solutions to reduce airborne noise being emitted by vacuum cleaners. It has been seen that blowers used in vacuum cleaners are the main source of airborne noise and blade wakes are unavoidable in turbo machines.Focus of this whitepaper is to understand how to reduce sound intensity of vacuum cleaners and studying its effects on human hearing. ERS division in HCL proposes the design of a spiral enclosure for the blower in the vacuum cleaner. HCL suggests solutions to reduce airborne noise being emitted by vacuum cleaners. ERS division in HCL proposes the design of a spiral enclosure for the blower in the vacuum cleaner.
A Silencer is a part of the exhaust system of an automobile that plays a vital role. It needs to
have modes that are located away from the frequencies that the engine operates at, whether the engine be
idling or running at the maximum amount of revolutions per second. The purpose of the design project
performed was to determine which modes are very high and may affect the automobile adversely while in
operation. Research was performed prior to the test to determine which frequencies to look for modes at.
It was determined to conduct the experiment so data from 20 Hz to 20 KHz could be collected. The force
was generated by running the engine at different speed. Acceleration is measured by using FFT analyzer
by selecting the points on the Silencer were chosen, after looking at the data and determined to be under
damped. Therefore, our design study suggests increasing the mass, increase the damping, or providing a
negative stiffness to make the silencer more damped.
The purpose of this report is also to the study the harmful effects of noise caused by it on Engine.
In India, the transportation sector is growing rapidly and number of vehicles on Indian roads is increasing
at very fast rate. This has lead to overcrowded roads and noise pollution. Engine vibration is one of the
major source of noise in vehicles. So, it is necessary to study noise generated by four stroke petrol engine.
The study of noise generated by four stroke petrol engine is carried out with or without mufflers to check
the effectiveness of the muffler
As member of the Product Group "Air Filters" within the Eurovent Association, I am proud to announce that the first edition of the guidebook "Air Filters for General Ventilation" has been released.
Among all the main arguments related to air filtration, I would like to highlight the following:
1. New EN ISO 16890: an overview on filter classification according to the brand new standard
2. Maintenance: a critical and important topic for all the applications of air filters
3. Energy efficiency: because energy saving is not only money, but mainly an ethical choice
Accelerate your Kubernetes clusters with Varnish CachingThijs Feryn
A presentation about the usage and availability of Varnish on Kubernetes. This talk explores the capabilities of Varnish caching and shows how to use the Varnish Helm chart to deploy it to Kubernetes.
This presentation was delivered at K8SUG Singapore. See https://feryn.eu/presentations/accelerate-your-kubernetes-clusters-with-varnish-caching-k8sug-singapore-28-2024 for more details.
LF Energy Webinar: Electrical Grid Modelling and Simulation Through PowSyBl -...DanBrown980551
Do you want to learn how to model and simulate an electrical network from scratch in under an hour?
Then welcome to this PowSyBl workshop, hosted by Rte, the French Transmission System Operator (TSO)!
During the webinar, you will discover the PowSyBl ecosystem as well as handle and study an electrical network through an interactive Python notebook.
PowSyBl is an open source project hosted by LF Energy, which offers a comprehensive set of features for electrical grid modelling and simulation. Among other advanced features, PowSyBl provides:
- A fully editable and extendable library for grid component modelling;
- Visualization tools to display your network;
- Grid simulation tools, such as power flows, security analyses (with or without remedial actions) and sensitivity analyses;
The framework is mostly written in Java, with a Python binding so that Python developers can access PowSyBl functionalities as well.
What you will learn during the webinar:
- For beginners: discover PowSyBl's functionalities through a quick general presentation and the notebook, without needing any expert coding skills;
- For advanced developers: master the skills to efficiently apply PowSyBl functionalities to your real-world scenarios.
Software Delivery At the Speed of AI: Inflectra Invests In AI-Powered QualityInflectra
In this insightful webinar, Inflectra explores how artificial intelligence (AI) is transforming software development and testing. Discover how AI-powered tools are revolutionizing every stage of the software development lifecycle (SDLC), from design and prototyping to testing, deployment, and monitoring.
Learn about:
• The Future of Testing: How AI is shifting testing towards verification, analysis, and higher-level skills, while reducing repetitive tasks.
• Test Automation: How AI-powered test case generation, optimization, and self-healing tests are making testing more efficient and effective.
• Visual Testing: Explore the emerging capabilities of AI in visual testing and how it's set to revolutionize UI verification.
• Inflectra's AI Solutions: See demonstrations of Inflectra's cutting-edge AI tools like the ChatGPT plugin and Azure Open AI platform, designed to streamline your testing process.
Whether you're a developer, tester, or QA professional, this webinar will give you valuable insights into how AI is shaping the future of software delivery.
Epistemic Interaction - tuning interfaces to provide information for AI supportAlan Dix
Paper presented at SYNERGY workshop at AVI 2024, Genoa, Italy. 3rd June 2024
https://alandix.com/academic/papers/synergy2024-epistemic/
As machine learning integrates deeper into human-computer interactions, the concept of epistemic interaction emerges, aiming to refine these interactions to enhance system adaptability. This approach encourages minor, intentional adjustments in user behaviour to enrich the data available for system learning. This paper introduces epistemic interaction within the context of human-system communication, illustrating how deliberate interaction design can improve system understanding and adaptation. Through concrete examples, we demonstrate the potential of epistemic interaction to significantly advance human-computer interaction by leveraging intuitive human communication strategies to inform system design and functionality, offering a novel pathway for enriching user-system engagements.
PHP Frameworks: I want to break free (IPC Berlin 2024)Ralf Eggert
In this presentation, we examine the challenges and limitations of relying too heavily on PHP frameworks in web development. We discuss the history of PHP and its frameworks to understand how this dependence has evolved. The focus will be on providing concrete tips and strategies to reduce reliance on these frameworks, based on real-world examples and practical considerations. The goal is to equip developers with the skills and knowledge to create more flexible and future-proof web applications. We'll explore the importance of maintaining autonomy in a rapidly changing tech landscape and how to make informed decisions in PHP development.
This talk is aimed at encouraging a more independent approach to using PHP frameworks, moving towards a more flexible and future-proof approach to PHP development.
The Art of the Pitch: WordPress Relationships and SalesLaura Byrne
Clients don’t know what they don’t know. What web solutions are right for them? How does WordPress come into the picture? How do you make sure you understand scope and timeline? What do you do if sometime changes?
All these questions and more will be explored as we talk about matching clients’ needs with what your agency offers without pulling teeth or pulling your hair out. Practical tips, and strategies for successful relationship building that leads to closing the deal.
Key Trends Shaping the Future of Infrastructure.pdfCheryl Hung
Keynote at DIGIT West Expo, Glasgow on 29 May 2024.
Cheryl Hung, ochery.com
Sr Director, Infrastructure Ecosystem, Arm.
The key trends across hardware, cloud and open-source; exploring how these areas are likely to mature and develop over the short and long-term, and then considering how organisations can position themselves to adapt and thrive.
Smart TV Buyer Insights Survey 2024 by 91mobiles.pdf91mobiles
91mobiles recently conducted a Smart TV Buyer Insights Survey in which we asked over 3,000 respondents about the TV they own, aspects they look at on a new TV, and their TV buying preferences.
Essentials of Automations: Optimizing FME Workflows with ParametersSafe Software
Are you looking to streamline your workflows and boost your projects’ efficiency? Do you find yourself searching for ways to add flexibility and control over your FME workflows? If so, you’re in the right place.
Join us for an insightful dive into the world of FME parameters, a critical element in optimizing workflow efficiency. This webinar marks the beginning of our three-part “Essentials of Automation” series. This first webinar is designed to equip you with the knowledge and skills to utilize parameters effectively: enhancing the flexibility, maintainability, and user control of your FME projects.
Here’s what you’ll gain:
- Essentials of FME Parameters: Understand the pivotal role of parameters, including Reader/Writer, Transformer, User, and FME Flow categories. Discover how they are the key to unlocking automation and optimization within your workflows.
- Practical Applications in FME Form: Delve into key user parameter types including choice, connections, and file URLs. Allow users to control how a workflow runs, making your workflows more reusable. Learn to import values and deliver the best user experience for your workflows while enhancing accuracy.
- Optimization Strategies in FME Flow: Explore the creation and strategic deployment of parameters in FME Flow, including the use of deployment and geometry parameters, to maximize workflow efficiency.
- Pro Tips for Success: Gain insights on parameterizing connections and leveraging new features like Conditional Visibility for clarity and simplicity.
We’ll wrap up with a glimpse into future webinars, followed by a Q&A session to address your specific questions surrounding this topic.
Don’t miss this opportunity to elevate your FME expertise and drive your projects to new heights of efficiency.
Essentials of Automations: Optimizing FME Workflows with Parameters
D013122127
1. IOSR Journal of Mechanical and Civil Engineering (IOSR-JMCE)
e-ISSN: 2278-1684,p-ISSN: 2320-334X, Volume 13, Issue 1 Ver. II (Jan. - Feb. 2016), PP 21-27
www.iosrjournals.org
DOI: 10.9790/1684-13122127 www.iosrjournals.org 21 | Page
Experimental and CFD Analysis of Vacuum Cleaner Exhaust
Muffler
P. P. Kale1*
, M. B. Patil2
, D. N. Korade1
, K. R. Jagtap1
1
Mechanical Engineering Department, Sinhgad Institute of Technology and Science, Narhe, Pune,
Maharashtra-411041, India
2
Emerson Innovation Center, Hinjewadi Phase-II Pune, Maharashtra-411057, India
Abstract: Vacuum cleaners are most commonly used housekeeping and industrial equipment and it is also
most powerful source of noise. A reduction of this noise has many advantages, especially in commercial
applications. In this work a wet and dry type vacuum cleaner (WD1450) is investigated for exhaust noise.
Exhaust air of vacuum cleaner coming with high velocity is one of the main sources of noise in vacuum cleaner.
To reduce exhaust noise of vacuum cleaner absorptive muffler is used. Aerodynamic performance of exhaust
muffler is investigated by CFD (Computational Fluid Dynamic) method in terms of back pressure. With the help
of CFD, simulation of pressure distribution in the muffler is done. Back pressure is an important parameter for
muffler performance and it is predicated by CFD technique. Experimentation is done to determine the effect of
muffler on the performance of a vacuum cleaner and amount of noise reduced. Efficiency and exhaust noise of
the vacuum cleaner is reduced by 11.23% and 1.1 dB respectively by using absorptive muffler.
Keywords: Absorptive muffler, Backpressure, CFD analysis, Vacuum cleaner noise, Wet and dry vacuum
cleaner.
I. Introduction
Vacuum cleaner is a device which uses vacuum pressure to collect dust and dirt by using an suction
unit. It is usually used to collect dust and dirt from floors and other surfaces such as furniture, carpet, etc.
Vacuum cleaners are most commonly use housekeeping equipment and it is also most powerful source of noise.
A reduction of this noise has many advantages, especially in commercial applications. [1]
Vacuum cleaner noise consists of three main components. First one is airborne, from air movement
caused by the centrifugal fan, motor rotation and exhaust. Second is structure borne, from the vibration of the
housing excited by the unbalanced rotation of the motor and fan. Third is mechanical, such as commutator brush
friction and bearing noise. The overall result is a sound spectrum containing random broadband noise with
higher level tonal components. [2]
An exhaust air of vacuum cleaner coming with high velocity is one of the main source of noise in
vacuum cleaner. To reduce exhaust noise of vacuum cleaner absorptive muffler is used. Absorptive muffler uses
porous material for the reduction of sound. Due to presence of muffler backpressure is created and it is an
important parameter for performance of the muffler. Generally, reduction in exhaust noise and the backpressure
are inversely proportional to each other. So in this paper the effect of absorptive muffler on the performance of a
vacuum cleaner and amount of exhaust noise reduce is investigated.
In this work a wet and dry type vacuum cleaner (WD1450) is investigated for exhaust noise. Operating
air intake is from the front side of drum and exhaust air is from the back side of drum. The electric motor is
placed above the drum in the center top portion of vacuum cleaner. 6.0 Peak HP Motor provides powerful
suction to handle tough jobsite cleanup. Drum size is 14 gallons. Filter used in a WD1450 wet and dry vacuum
cleaner is pleated filter (3-layer Fine Dust Filter) which captures fine dust particles. Scroll Noise Reduction is a
patented feature that provides quiet operation by precisely controlling the flow of air through the vacuum
cleaner.
II. Literature Survey
Mirko Cudina and Jurij Prezelj [1] studied the noise generating mechanisms of vacuum cleaner suction
unit. In this paper author has given an overview of mechanical, electromagnetic and aerodynamic noise origin.
Blower and electric motor used for suction in a vacuum cleaner is the main source of noise and this noise is
mechanical, electromagnetic and aerodynamic in nature.
E. Altmsoy, H. Erol [2] done an experimental study on Vibro-acoustic characteristics of a wet and dry
type vacuum cleaner. The effect of the vibrating surface on to the total noise created by a vacuum cleaner is
investigated. Vibro-acoustic characteristics of the sample wet and dry type vacuum cleaner is studied by the
author.
2. Experimental And CFD Analysis Of Vacuum Cleaner Exhaust Muffler
DOI: 10.9790/1684-13122127 www.iosrjournals.org 22 | Page
Roshun Paurobally [3] worked on active noise control of vacuum cleaner. In this paper author has
installed an active noise control (ANC) system. Active noise control has been implemented in an industrial
backpack vacuum cleaner. The aim is to attenuate a low frequency tonal component to reduce the annoyance
while reducing the overall noise level. The overall noise level is reduced by about 2 dBA.
Shital Shah et al. [4] examine practical approach towards muffler design, development and prototype
validation. Practical approach is used to design, develop and prototype of reactive muffler. Practical approach
gives advantages over conventional methods. In this paper CAE tool is also used for managing critical
requirement like sound and backpressure.
Sudarshan Dilip Pangavhane [5] et al. studied experimental and CFD analysis of a perforated inner
pipe muffler for the prediction of backpressure. Author has tested three mufflers in lab with varying porosity. As
porosity increase, sudden decrease in backpressure is observed by the author. In this paper CFD analysis was
used to investigate the effect of change in dimensions of perforation diameter and change in porosity of internal
tube and the CFD results is compared with experimental results. It is found that the porosity of the muffler has
distinct effect on the Backpressure.
Zeynep Parlar [6] et al. examines acoustic and flow field of a perforated muffler design. Numerically
and experimentally reactive perforated muffler is investigated by the author. In this study, acoustic and flow
characteristic of a perforated, cross-flow, three pass muffler were analyzed. Sound pressure contours were
obtained from COMSOL by doing acoustical analysis of present muffler. Numerical calculation was done for
calculating transmission loss.
A.Selamet et al. [7] studied acoustic attenuation of hybrid silencers. Perforated concentric silencer
filled with continuous strand fibbers was investigated experimentally and theoretically for noise reduction.
Acoustic attenuation was done by using one dimensional analytical and three-dimensional boundary element
methods (BEM) are used.
III. Noise Audit
Noise audit is the method use for characterizing and to rank the potential noise sources in an operating
device, where information obtained from the audit can be used to adapt the most effective noise reduction
strategy. [3]
1. Noise Audit Process
Vacuum cleaner is kept at the center and allowed to run for about 5 minutes.
Sound Pressure Level measurement is carried out using Personal Acoustic Analyzer (PAA3) which a
handheld SPL measurement device is giving 31 band 1/3 rd octave analyses.
The measurement is carried out at a distance of 1 meter in 8 directions at an angle of 45 degrees in
anticlockwise directions and 3 feet above the ground level.
Take the sound pressure level readings at 8 positions for each of the configuration.
Following are 6 configurations, consider in the noise audit process.
(a) (b)
Fig. 1 (a) C1: Vacuum cleaner with hose, (b) C2: Vacuum cleaner without hose
3. Experimental And CFD Analysis Of Vacuum Cleaner Exhaust Muffler
DOI: 10.9790/1684-13122127 www.iosrjournals.org 23 | Page
(a) (b)
Fig. 2 (a) C3: Vacuum cleaner without drum with filter, (b) C4: Vacuum suction unit without drum and
filter
(a) (b)
Fig. 3 (a) C5: Suction unit (Motor + Impeller), (b) C6: Suction unit with only motor
After characterizing the different sources and path of noise, evaluation of the noise audit process is
done. Once all process gets completed, different noise sources are ranked depending upon their noise emitting
capability. This noise sources are ranked according to their noise emitting capability in order to focus on to the
most power full noise source first. [4]
Fig. 4 Sound power level of different configuration
From noise audit, we get two main sources of noise first is a motor and blower assembly that is suction
unit. A second source of noise is exhaust noise. The motor and blower assembly are purchased from an outside
vendor, and redesigning the motor is not an option. The exhaust air, which has accounted for the majority of
noise, will be concentrated to reduce the noise level and improve the sound quality of the noise produced.
IV. Experimental Setup
1. Overall Sound Pressure Level Measurement Test Procedure
Vacuum cleaner is kept at the center and allowed to run for about 5 minutes .Sound pressure level
measurement is carried out using a personal acoustic analyzer (PAA3) which a handheld SPL measurement
device is giving 31 band 1/3 rd octave analyses. The overall sound pressure level measurement is done in 8
4. Experimental And CFD Analysis Of Vacuum Cleaner Exhaust Muffler
DOI: 10.9790/1684-13122127 www.iosrjournals.org 24 | Page
directions. Measurement is carried out at a distance of 1 meter at an angle of 45 degrees in anticlockwise
directions and 3 feet above the ground level is shown in Fig. 5.
Fig. 5 Experimental setup of overall sound pressure level measurement.
2. Standard Air Performance Test Procedure
Standard air performance test is carried out as per ASTM F 588-03 standard. A plenum chamber is an
essential part of this test; such a plenum is provided in the lab. The test procedure is outlined below.
Record barometric pressure, wet bulb temperature, and dry bulb temperature within 6 feet of the test area at
the beginning of each test
Connect the vacuum cleaner to the appropriate inlet on the plenum.
Ensure that the hose is free of kinks or abrupt bends.
Various sizes of orifice plates can be installed at the top of the plenum chamber. Remove any orifice plate
from this location. We will refer to this as an “open orifice” condition.
Run the vacuum cleaner for two minutes, under the “open orifice” condition to allow the motor to reach its
operating temperature.
Install the 2.5 inch orifice plate, with the vacuum continuing to run.
Wait 10 seconds and record the suction and the current.
Remove the 2.5 inch orifice and allow the vacuum to run for 1 minute at open orifice condition.
Repeat these measurements for the 2.25, 2.0, 1.75, 1.50, 1.375, 1.25, 1.125, 1.0, 0.875, 0.75, 0.625, 0.50,
0.375, 0.25, and 0.0 inches orifice plates.
Fig. 6 Experimental setup for standard performance test
[A]: Dry and Wet bulb thermometer. [B]: Orifice plates of different diameter inserted into Plenum chamber.
[C]: Experimental arrangement of air performance test. [D]: Well type monometer.
V. CFD Analysis
ANSYS ICEM 15 was used for meshing and ANSYS CFX 15 was used for computational fluid
dynamic analysis. Air with fix velocity is passing through absorptive muffler and pressure drop across the
muffler is same as the back pressure acting on the vacuum cleaner. The solver implemented was pressure based
5. Experimental And CFD Analysis Of Vacuum Cleaner Exhaust Muffler
DOI: 10.9790/1684-13122127 www.iosrjournals.org 25 | Page
as it is used for incompressible flows. Fig.7 shows CAD model and working principle of absorptive muffler.
[5][6]
Fig. 7 CAD model and working principle
Boundary conditions and Assumption
Flow is considered to be steady.
Air is considered as the fluid for computations.
Flow considered as Turbulent (K-ε Model).
Inlet, considered as a velocity boundary condition with 35.47 m/s.
Outlet considered as pressure outlet opened to the atmosphere.
VI. Result And Discussion
1. Overall Sound Pressure Level Measurement Test With and Without Muffler Results
The sound pressure level emitted at front (suction) side does not differ much, ranging from 84.1 to 84.7
dB. While the sound emitted from the exhaust side is 88.2 dB as shown in fig. 8 (a). From this overall sound
pressure level measurement test one can surely recognize that the sound emitted from the exhaust side is more
than that from the suction side. So from this it is clear that exhaust noise is one of the main sources of noise.
To overcome exhaust noise problem absorptive muffler was used. Absorption type muffler uses porous material
for the reduction of sound. Porous material used in present muffler is Open cell polyester polyurethane foam
with 20 pores per inch and 12.7 mm thickness. Exhaust air is passing axially through a single layer of foam.
Noise reduced by muffler is 1.1 dB only as shown in fig. 8 (b).
(a) (b)
Fig.8 Overall sound pressure level measurement (a) without muffler and (b) with muffler
2. CFD Analysis Results
CFD analysis of absorptive muffler was done in two different ways. First analysis of muffler was done
without porous material. In this analysis only the effect of the structure on the flow of air and pressure
distribution was studied. Then second analysis was done with porous material. In this analysis effect of porous
material on the flow of air and pressure distribution was studied.
6. Experimental And CFD Analysis Of Vacuum Cleaner Exhaust Muffler
DOI: 10.9790/1684-13122127 www.iosrjournals.org 26 | Page
For flow analysis of the muffler it was meshed using Ansys ICEM with tetrahedral elements. Since the
muffler has a small wall thickness, which causes problems during mesh generation. Thus hexagonal mesh was
not used. In addition to this boundary layers were generated for the outside liner of the muffler. Fig. 9 shows
velocity plot for absorptive muffler without porous material and with porous material. [6][7]
(a) (b)
Fig.9 velocity plot for muffler (a) without porous material (b) with porous material
Table 1 Mesh Statistics
Muffler Without Porous material With Porous material
Element Number 1916469 2216472
Node Number 537788 617417
The performance of muffler is mainly depends on the backpressure. Aerodynamic performance of
exhaust muffler is investigated by the CFD method in terms of back pressure. With the help of CFD, simulation
of pressure distribution in the muffler is done. Back pressure is an important parameter for muffler performance
and it is predicated by CFD technique. From CFD we get pressure drop and pressure drop is nothing but the
backpressure. Backpressure for muffler without porous material was 428.11 Pa where as backpressure for
muffler with porous material was 985.71 Pa.
3. Standard Air Performance Test With & Without Muffler Results
To reduce exhaust noise of a vacuum cleaner, we are using absorptive muffler. Porous material used in
absorptive muffler is Open cell polyester polyurethane foam with 20 pores per inch, density of 22.4258 kg/m3
and thickness of foam is 12.7 mm. Absorptive muffler creates back pressure due to pressure drop. Back pressure
plays a vital role in the performance of a vacuum cleaner. So amount of back pressure created by muffler is an
important parameter for muffler design.
The effect of muffler on the efficiency of vacuum cleaner is shown in fig.10. Use of absorptive muffler
reduces the efficiency of vacuum cleaner by 1.645%.
.
Fig. 10 Orifice diameter Vs efficiency
Air watt is a measurement unit of the effectiveness of vacuum cleaners which refers to airflow and the
amount of power (watts) a vacuum cleaner produces and uses. It can also be referred to as a measurement of the
energy of the air flowing through an opening. Fig. 11 shows the effect of the muffler on the air watt of vacuum
cleaner. Air watt of vacuum cleaner is reduced by 16.603W due to use of muffler as compare to without muffler.
7. Experimental And CFD Analysis Of Vacuum Cleaner Exhaust Muffler
DOI: 10.9790/1684-13122127 www.iosrjournals.org 27 | Page
Fig. 11 Orifice diameter Vs air watt
VII. Conclusion
After doing this experimental and CFD work following conclusions can be drawn:
1. WD 1450 wet and dry type vacuum cleaner is used for investigation of exhaust noise. To reduce exhaust
noise of vacuum cleaner; absorptive muffler is used.
2. In vacuum cleaner two main sources of noise are present. First is a motor and blower assembly that is
suction unit and second is exhaust noise. In this work focus is given on exhaust noise. For exhaust noise
reduction, absorptive muffler is used. Noise reduced by absorptive muffler is 1.1 dB.
3. CFD analysis of absorptive muffler was done in two different ways. First analysis of the muffler was done
without porous material and second analysis was done with porous material.
4. Backpressure for muffler without porous material was 428.11 Pa where as backpressure for muffler with
porous material was 985.71 Pa.
5. Efficiency of vacuum cleaner is reduced by 11.23% due to use of a muffler in vacuum cleaner. Also air watt
of vacuum cleaner is reduced by 11.27% due to use of muffler as compare to without muffler.
References
[1] Mirko Cudina, Jurij Prezelj, Noise generation by vacuum cleaner suction units part I noise generating mechanism-an overview,
International Journal of Applied acoustics, 68, 2007, 491-502.
[2] E. Altinsoy, H. Erol, An experimental study on vibro-acoustics characteristics of a wet and dry type vacuum cleaner, Seventh
international congress on sound and vibration, Germany, 2000, 667-674.
[3] Roshun Paurobally, Active control of noise from a vacuum cleaner, The thirteenth international congress on sound and vibration ,
Vienna, Austria, 2006.
[4] S. Shah, Saisankaranarayana K, K. Hatti, D. Thombare, A practical approach towards muffler design, development and prototype
validation, SAE International Journal of commercial vehicle, 2010.
[5] S. Pangavhane, A. Ubale, V. Tandon, D. Pangavhane, Experimental and CFD analysis of a perforated inner pipe muffler for the
predication of backpressure, International Journal of Engineering & Technology, 5(5), 2013, 3940-3950.
[6] Z. Parlar, S. Ari, R. Yilmaz, E. Ozdemir, A. Kahraman , Acoustic and flow field analysis of a perforated muffler design, World
academy of science, engineering and techanology, Vol 7, 2013, 603-607.
[7] A. Selamet, I. Lee, N. Huff, Acoustic attenuation of hybrid silencer, International Journal of sound and vibration, 262, 2003, 509-
527.