Washing Machine Research Articles

Design of a Washing Machine with a Stochastic Approach

A washing machine is a household appliance that has an interesting and complex dynamicalbehavior, which can be well described by a set of nonlinear differential equations. When analyzing the dynamics of a washing machine, the steady state motion (periodic solution) is an important response to consider and can be evaluated as a solution of a periodic boundary-valueproblem. The unbalance generated by the unevenly distribution of clothes during centrifugationis highly random and, therefore, a stochastic model is necessary to take this characteristic intoaccount. The novelty of this paper consists in the analysis of a washing machine dynamics considering the uncertainty in the unbalance. Therefore, a stochastic model is proposed for the dynamics of a washing machine. The steady state solutions are calculated using the shootingmethod combined with a sequential continuation to evaluate it across all the spin speeds of the machine. The probability distributions of the washing machine vibration at those different spin speeds are approximated using Monte Carlo simulations. The impact of the random unbalance in the vibration amplitude of the washing machine is also investigated and consists in a keyinput for the fatigue design of many components.

Development and Efficiency Evaluation of Microplastic Removal Filter for Laundry Machines

Microplastics contained in laundry wastewater are identified as the main cause of marine microplastics, accounting for approximately 35% of marine microplastics. In this study, a four-stage microplastic filter for laundry wastewater was developed and the removal rates of microplastics, COD, SS, and turbidity were checked through 50 tests to confirm the efficiency of the filter. The microplastic removal rate was confirmed using μFTIR with a high efficiency of 98.5% on average for 50 tests. The microplastics contained in laundry wastewater were identified as 57% PE, 9% PET, 9% PA, 8% PU, 8% PP, 6% PPMA, and 3% PAN. COD was measured using the COD manganese method, and the COD removal rate of the laundry wastewater filter was an average of 92% for 50 times. SS was verified by filtration using a vacuum pump and the average removal rate was 80% during 50 tests. Turbidity was confirmed with an average removal rate of 88% using a turbidity meter. As a result of the experiment, it was confirmed that when the developed filter was installed in laundry wastewater, not only microplastics but also various water pollutants were reduced. In addition, the water quality pollution index showing the highest correlation with microplastics in laundry wastewater was SS, and the p-value was confirmed to be 0.000.

Mitigation of microfibers in laundry effluent: Investigation of luffa fibers as an eco-friendly filtration system.

Domestic laundry wastewater is a major contributor to microfiber emissions in the aquatic environment. Among several mitigation measures, the use of external filters to capture microfibers from wastewater is one of the most efficient and commercially viable methods. This study attempted to develop an eco-friendly filtration medium to filter microfibers in laundry wastewater using luffa cylindrica fibers. Sourced luffa fibers were made into tight rolls and stacked in a filtration column to filter the effluent. The analysis showed that the alkali-treated luffa fiber rolls were more effective in filtering the microfibers than untreated luffa fibers. Hence, the alkali treatment process was optimized for better performance; an alkali concentration of 5.8%, treatment time of 5h, and 37°C temperature provide better performance. The characterization of alkali-treated luffa fibers showed significant changes in the morphology and removal of lignin and hemicellulose components, enhancing the physical adsorption of microfibers on the surface. The experimental filtration results showed that the developed filter can effectively remove up to 93% of microfibers from laundry effluent, and the efficiency remained superior for up to 15 filtrations. Furthermore, an increase in filtration leads to the accumulation of detergents in the luffa net-like vascular structure and reduced effectiveness. The use of the developed product in a real-time washing machine outlet was found to be effective with an efficiency of 98%. The developed product is a versatile and cost-effective solution, suitable for use in domestic washing machines. Its simplicity and ease of integration make it an effective and eco-friendly alternative for filtering microfibers from laundry effluent. The future direction of the study also suggests a sustainable disposal method for luffa fibers using it as a matrix material in red soil-based thermal or sound insulation panels and restricting the reach of microfibers into the environment.

The mechanism of microplastic fibers release in a front-loading washing machine

Microplastic fibers (with a diameter of less than 5 mm) generated by synthetic textiles during the washing machine laundering process are considered to be one of the primary sources of pollution in both water and land environments. This study aimed to investigate the impact of novel combinations of washing parameters on the release of microplastic fibers. A wall-mounted drum washing machine was chosen as the subject of research in order to comprehensively examine the influence of washing conditions on the release of microplastic fibers during the washing process. The results showed that the length of shedding microplastic fibers were between 300 and 400 µm. The diameter of the shedding microplastic fibers was 13 ± 1 µm. High amounts of water and high load can lead to an increase of fiber microplastic release. Abrasion between fabrics influenced the release of microplastic fibers according to the movement of the fabric, which could affect fiber directional migration conditions. The findings on microplastic fibers release will help in the development of better front-loading washers.

Reducing Water Consumption on a Student Campus Through Communication Campaigns

Water management is a significant component of ensuring the pursuit of sustainable goals in an organization. Universities are known actors committed to developing responsible behaviors in students, including water consumption. The present research investigates the changes in student water-related behaviors in campus living, due to an information and persuasion campaign that took place in the oldest university in Western Romania. The research is based on a quantitative statistical approach highlighting the changes in students’ self-perceived importance allocated to water use and water saving, due to a communication campaign that took place on campus premises, with over 6000 residents. The pre- and post-campaign questionnaire rendered over 800 valid responses, ensuring the representativeness of the results for the given campus. The campaign described in the research targeted raising students’ awareness of sustainability issues and nudging pro-environment behaviors. The water management component of the campaign aimed at reducing water consumption in student campus living without affecting cleanness and personal hygiene, by making better use of the existing resources. Students responded positively to nudge messages for the reduction in showering time and a better use of laundry machines. The campaign led to a measurable reduction in water waste, but the results need to be reinforced through new campaigning, to maintain the water-saving behavior in the student population.

Comprehensive exergy, exergoeconomic, exergoenvironmental and energy audit assessment in a textile factory

In the industry, the discussion of energy and exergy analysis has gained increasing importance due to human needs from the past to the present. In the textile industry, this analysis has only been implemented in a limited manner and in isolated units. Specifically, in the dyeing, printing, and finishing units, steam and hot oil energy is utilized for heating processes. This heating requirement is met by steam boilers and hot oil boilers, which are essential for the operation of an integrated system. Identifying factors of energy loss and pollutant production, along with applying energy improvement techniques in textile factories, can significantly reduce the problems associated with fossil fuels. To identify potential energy and environmental improvements, an energy audit was conducted throughout the Borujerd Textile Factory in Iran, which goes beyond previous fragmented and isolated assessments to provide a comprehensive review of the entire system. This audit integrated thermography and flue gas analysis to enhance the accuracy and effectiveness of performance evaluation. By performing exergy, exergoeconomic, and exergoenvironmental (4E) analyses, the performance of the existing system was evaluated, providing a comprehensive overview of efficiency and the potential for improvements and optimizations. Environmental impact analysis was conducted using life cycle assessment in SimaPro for different sections of the plant. The results indicate that the most significant exergy destruction occurs in steam boilers and hot oil boilers, totaling 33.5 MW and 91%, respectively, as well as the washing after printing machine in the dyeing department, accounting for 3% of total exergy destruction due to high energy wastage and low efficiency in these devices. The cost rate of overall exergy destruction is estimated at $61.1 per hour. The highest environmental impacts were observed for steam boilers and the pad steam machine in the dyeing department, primarily due to the equipment's structure and the use of polluting materials that contribute to emissions from these devices. After the energy audit, the most effective solutions to the identified problems were proposed. It was also determined that the most significant heat loss occurs in pad steam machines, washing after printing, and bleaching washing machines.

Hand Injuries Due to Top Loader Automatic Washing Machine: Experience from Oman with Three Case Reports and Literature Review

Hand Injuries Due to Top Loader Automatic Washing Machine: Experience from Oman with Three Case Reports and Literature Review

Circuit Privacy for FHEW/TFHE-Style Fully Homomorphic Encryption in Practice

A fully homomorphic encryption (FHE) scheme allows a client to encrypt and delegate its data to a server that performs computation on the encrypted data that the client can then decrypt. While FHE gives confidentiality to clients' data, it does not protect the server's input and computation. Nevertheless, FHE schemes are still helpful in building delegation protocols that reduce communication complexity, as the ciphertext's size is independent of the size of the computation performed on them. We can further extend FHE by a property called circuit privacy, which guarantees that the result of computing on ciphertexts reveals no information on the computed function and the inputs of the server. Thereby, circuit private FHE gives rise to round optimal and communication efficient secure two-party computation protocols. Unfortunately, despite significant efforts and much work put into the efficiency and practical implementations of FHE schemes, very little has been done to provide useful and practical FHE supporting circuit privacy. In this work, we address this gap and design the first randomized bootstrapping algorithm whose single invocation sanitizes a ciphertext and, consequently, serves as a tool to provide circuit privacy. We give an extensive analysis, propose parameters, and provide a C++ implementation of our scheme. Our bootstrapping can sanitize a ciphertext to achieve circuit privacy at an 80-bit statistical security level in between 1.3 and 0.9 seconds, depending which Gaussian sampling algorithm is used, and whether the parameter set targets a fast Fourier or a number theoretic transform-based implementation. In addition, we can perform non-sanitized bootstrapping in around 0.27 or 0.14 seconds. Crucially, we do not need to increase the parameters to perform computation before or after sanitization takes place. For comparison's sake, we revisit the Ducas-Stehlé washing machine method. In particular, we give a tight analysis, estimate efficiency, review old, and provide new parameters.

Development and Evaluation of a Dual-Powered Cassava Peeling and Washing Machine

Cassava is abundantly available in most farms across the country, and it can be readily employed to meet the nation’s vast need for food if appropriate machinery is in place. Therefore, this project developed a vertical stand cassava peeling and washing machine that could be powered electrically or manually using locally sourced materials. This was actualised through comprehensive engineering design fabrication and assembly. The machine was tested and performed satisfactorily in peeling and washing any size and shape of cassava tubers. Performance evaluation was carried out using 5, 10 and 15 tubers, with varying volumes of water from 15 to 50 litres and operating speeds of 360, 380 and 420 rpm. The peeling and washing efficiency of the machine depends on the number of cassava tubers, the volume of water in the peeling and washing chamber, and the speed of the machine when electrically powered. However, the peeling and washing efficiency of the machine only depends on the number of cassava tubers and the volume of water in the peeling and washing chamber when manually powered. The machine performed optimally when loaded with 15 tubers of cassava and 50 litres of water when electrically operated at 480 rpm. The highest peeling efficiency of 87% was obtained when loaded with 15 tubers and operated at a speed of 420 rpm. A throughput of 160 kg/hr was achieved at full capacity when powered electrically.

Assessment of Replacing Gas Boilers with Heat Pumps for Hot Water Preparation in Car Washes

The study provides a complex analysis for replacement of the natural gas boilers with air to water heat pumps, as the heat source for the hot water to be used in the car washing machines. It was considered heat pumps with R744 and with R290 as refrigerant, and it was proved that even heat pumps that seem to be undersized at negative temperatures, can still provide the required heat for 70 % of the full operating time. The feasibility was determined to be higher for the heat pumps with R290 and the payback period is lower than 2 years for the average car washing frequency of less than 5 cars washed / hour. The hot water storage tank can increase the period of continuous operation even at negative ambient temperature when the heat pump seems to be undersized.

AI-Driven Smart Washing Machine with Automatic Drying: Modeling and Optimizing Energy and Water Consumption

AI-Driven Smart Washing Machine with Automatic Drying: Modeling and Optimizing Energy and Water Consumption

Design of a New Washing Machine to Clean the Needle Bed of an Electronic Flat Knitting Machine

Design of a New Washing Machine to Clean the Needle Bed of an Electronic Flat Knitting Machine

Sterilization and Filter Performance of Nano- and Microfibrous Facemask Filters - Electrospinning and Restoration of Charges for Competitive Sustainable Alternatives.

Facemask materials have been under constant development to optimize filtration performance, wear comfort, and general resilience to chemical and mechanical stress. While single-use polypropylene meltblown membranes are the established go-to material for high-performing mask filters, they are neither sustainable nor particularly resistant to sterilization methods. Herein an in-depth analysis is provided of the sterilization efficiency, filtration efficiency, and breathing resistance of selected aerosol filters commonly implemented in facemasks, with a particular focus on the benefits of nanofibrous filters. After establishing a general overview over face mask filters and machine washing parameters required for successful decontamination, respective changes in filter performance and structure are presented. Sustainably manufactured, highly efficient, but also more fragile electrospun membranes not only offer competitive performance as well as a more environment-friendly production and degradation process, but also support a subsequent sterilization and recharging approach via alcohol exposition and drying in an electric field. It is further elaborated on the prospective sustainability of each material to offer a clear outlook on electrospun membranes as the most promising filter membranes of the future.

Research on intelligent vibration damping base of washing machine based on a stiffness-variable magnetorheological elastomer

Traditional washing machine vibration-damping bases have a fixed stiffness, which can lead to structural resonance when the motor’s excitation frequency aligns with the machine’s inherent vibration frequency during the washing and spinning processes. This not only amplifies the noise caused by vibrations but also accelerates the wear and tear of the internal components. In this study, a pioneering approach has been introduced, developing an intelligent vibration-damping base for drum washing machines based on the dynamics of a mass-spring-damped single-degree-of-freedom system. This innovative base is designed with variable stiffness magnetorheological elastomer, utilizing the dynamics of the mass-spring-damped system to adaptively counteract vibrations. A vibration transmission rate curve specific to drum washing machines has been derived, and an intelligent control strategy for the drum washing machine’s vibration-damping base has been proposed. Dynamic testing of the drum washing machine’s vibration-damping base was conducted to verify the effectiveness of the intelligent damping base. The intelligent damping base addresses the unavoidable low-frequency resonance issues of traditional passive damping bases in washing machines and overcomes the drawback that the performance parameters of traditional passive isolation structures cannot be changed once set, providing a new direction for the damping of household appliances.

Design optimization of vibration amplitude reduction based on virtual prototype and machine learning

The traditional design optimization of vibration amplitude reduction mainly has the disadvantages of low modeling and prediction accuracy as well as low optimization efficiency. Therefore, this paper presents a design optimization method for vibration amplitude reduction based on virtual prototyping and machine learning, which combines the high accuracy of numerical calculations with the efficiency of machine learning, overcoming the shortcomings of traditional methods. Firstly, sample points are collected through the design of experiments and virtual prototype simulation. Then, based on the sampled data, a prediction model for the relationship between the design parameters and the amplitude of the product is established using Genetic Algorithm-Support Vector Regression (GA-SVR). On the basis of the GA-SVR prediction model, a multi-objective optimization model of product is established, and Multiple Objectives Particle Swarm Optimization -entropy weight- Technique for Order Preference by Similarity to Ideal Solution (MOPSO-entropy weight-TOPSIS) is used to solve for the optimal design parameters. Finally, the washing machine suspension system is used as an example to verify the effectiveness of the model. The results show that, compared with the original design scheme, the design scheme obtained by the model can reduce the amplitude of the washing machine suspension system by 12.68%, and reduce the total weight of the counterweight by 7.35%. This method is conducive to the intelligent and efficient design optimization of vibration amplitude reduction, and is of great significance to product life cycle design.

Microbial Colonization, Biofilm Formation, and Malodour of Washing Machine Surfaces and Fabrics and the Evolution of Detergents in Response to Consumer Demands and Environmental Concerns.

Bacterial attachment and biofilm formation are associated with the contamination and fouling at several locations in a washing machine, which is a particularly complex environment made from a range of metal, polymer, and rubber components. Microorganisms also adhere to different types of clothing fibres during the laundering process as well as a range of sweat, skin particles, and other components. This can result in fouling of both washing machine surfaces and clothes and the production of malodours. This review gives an introduction into washing machine use and surfaces and discusses how biofilm production confers survival properties to the microorganisms. Microbial growth on washing machines and textiles is also discussed, as is their potential to produce volatiles. Changes in consumer attitudes with an emphasis on laundering and an overview regarding changes that have occurred in laundry habits are reviewed. Since it has been suggested that such changes have increased the risk of microorganisms surviving the laundering process, an understanding of the interactions of the microorganisms with the surface components alongside the production of sustainable detergents to meet consumer demands are needed to enhance the efficacy of new antimicrobial cleaning agents in these complex and dynamic environments.

User behavior and energy-saving potential of electric washing machines

With the intensification of the global energy crisis and the increase in environmental awareness, energy-saving problems related to household appliances have garnered widespread attention. Here, the usage patterns of electric washing machine users and their energy-saving potential was mainly explored, so as to improve the current situation that the influencing factors of existing research behaviors were not deep enough and the energy saving potential was not specific enough. A questionnaire survey was used to gather information on 20,840 users, including individual characteristics, energy-saving awareness, and usage behavior. The study analyzed the differences in users’ energy-saving awareness and behavior through a series of analysis methods, and evaluated the energy-saving and water-saving potential of electric washing machines. The results showed that user behavior such as washing mode, washing temperature, and the volume ratio of clothes significantly affected on the energy and water consumption of electric washing machines. Individual characteristics of users such as gender, age, educational background, and family income were strongly correlated with their awareness of and decisions made regarding energy conservation. Improving the energy efficiency of electric washing machines and optimizing user purchasing behavior could result in 38,787.54 GWh national energy savings potential, and 6.90 million tons of water-saving potential. This study will help manufacturers and government departments better understand consumers’ usage behavior regarding electric washing machines, which could allow them to modify their market strategies and bolster the promotion and education of energy efficiency labels for electric washing machines. This also could support the nation’s objectives for environmental preservation, water and energy conservation, and the sale of products with lesser energy efficiency.

Modeling industrial scale washing machine process using artificial neural networks

The paper presents a dynamic model of a typical industrial washing machine fed with hot water, cold water and steam. Since industrial scale washing machines are not expressly designed to be energy efficient, there is scope to reduce energy consumption and wastewater discharge through dynamic model analysis of washing programs and washing machine units as regards heating medium parameters and prices. The paper presents a construction of the dynamic model using Aspen Hysys software that provides data to determine optimized parameters of water and steam delivered to the washing unit. The model has been validated with real data delivered by the dedicated measuring software from the washing machine manufacturer. Finally, the paper presents an economic analysis and sensitivity analysis regarding energy prices with various media parameters. Results show that the price of the washing process can be reduced by 64% depending on the parameters of the heating medium.

Synthesis of Ultrathin Film PEGDMA Hydrogels Coated onto Different Surfaces by Atmospheric Pressure Plasma: Characterization and Potential Features for the Biomedical Field

AbstractThe preparation of resistant ultrathin film (utf) hydrogels coated onto different working surfaces (e.g., fabrics) is paying increasing attention as an advantageous strategy for customizing their resultant properties. More specifically, poly(ethylene glycol) (PEG)‐based utf‐hydrogels are relevant for their superior biocompatibility or antibiofouling properties. However, promoting the generation of poly(ethylene glycol) dimethacrylate (PEGDMA) cross‐links ideally without the use of initiators or other cross‐link agents, which might compromise the final bioactivity of the system, is complicated. Moreover, the actual synthesis techniques used for the preparation of such utf‐hydrogels face important drawbacks like high scale‐up costs or important geometrical restrictions, completely hindering its technological transfer. Herein, for the first time and easy and technologically scalable technology is reported for the synthesis and direct deposition of PEGDMA400 utf‐hydrogels onto different substrates based on atmospheric pressure nanosecond pulsed plasma approach. The advantages of the technology are explored and discussed, reporting the ready‐to‐use transparent coating of fabrics. After washing the samples using washing programs of a commercial laundry machine, coatings are still well adhered, showing excellent stability. Finally, the resultant properties of PEGDMA400 utf‐hydrogels are exhaustively characterized using in operando conditions in order to elucidate their potential capabilities in the biomedical field.

Green means go: The effect of a visualization tool towards increased use of renewable energy in households

There is a need to further develop digital and hardware tools to support consumers in the adaptation of their energy use to, for example, integrate renewable sources into it and/or reduce expenses. This paper presents an evaluation study of a tool, including its hardware and software versions, that supports consumers in their electricity consumption optimization, most notably concerning renewable energies for specific devices. We conducted a six-week study in Oldenburg, Germany involving 43 participants divided into three groups: one hardware and one digital variant each of an energy visualization tool, as well as a control group. We furthermore collected quantitative data on energy usage patterns and qualitative insights through semi-structured interviews. Here the participants received information about the percentage of renewable energy currently in the grid, and were asked to document their washing machine and dishwasher use. This paper provides insights into the perception of the proposed visualization tools achieved through semi-structured interviews, comparing the digital and hardware versions, while outlining the challenges of and possibilities for changing energy use behavior, especially regarding the time of day of an appliance's use. Even though the measurable influences of the tool were limited due to thresholds being reached too easily as a result of e.g. high wind levels generating higher-than-anticipated amounts of renewable energy, in terms of the amount of renewable energy use, slight improvements in the two test groups were observed compared to the control group. Regarding consumer behavior, changes in the appliances' use time show slightly higher improvement compared to the control group.