Search Results (70)

Blade tip leakage vortex (TLV) is a critical phenomenon in hydraulic machinery, which can significantly affect the internal flow characteristics and deteriorate the hydraulic performance. In this paper, the blade tip leakage flow and TLV characteristics in a novel dishwasher pump were investigated. The correlation between the vorticity distribution in various directions and the leakage vortices was established within a rotating coordinate system. The results show that the TLV in a composite impeller can be categorized into initial and secondary leakage vortices. The initial leakage vortex originates from the evolution of two corner vortices that initially form at different locations within the blade tip clearance. This vortex induces pressure fluctuations at the impeller inlet; its shedding is identified as the primary contributor to localized energy loss within the flow passage. These findings provide insights into TLVs in complex pump geometries and provide solutions for future pump optimization strategies. Full article

This study investigated how factors associated with Sinner’s principle—namely temperature, time, and the chemical composition of detergents—affected the antimicrobial efficacy of domestic dishwashers, particularly during short cycles. These are of particular interest, because many consumers refrain from using long cycles while it is still unclear if short cycles can provide a sufficient level of hygiene. Thus, we chose a range of bacterial strains, including standard test strains such as Micrococcus luteus and Enterococcus faecium, as well as important foodborne pathogens such as Escherichia coli, Staphylococcus aureus, and Salmonella enterica. To account for the complexity of dishwasher cycles, we correlated hygiene efficacy with area under the curve (AUC) measurements derived from the respective cycle profiles. Our findings revealed that the reductions in M. luteus and E. faecium were minimally affected by the reference detergent. In contrast, a high-tier market detergent demonstrated a significant decrease in bacterial counts. Notably, both strains exhibited reduced efficacy at a main cycle temperature of 45 °C, suggesting that temperatures below 50 °C might represent a critical threshold at which the hygiene efficacy of domestic dishwashing processes declines. However, since food-related pathogens were more susceptible to the dishwashing process, even lower temperatures might deliver a sufficient level of hygiene. Plotting the logarithmic reduction/AUC ratio against the AUC indicated that the main cycle contributed approximately 10-fold more to microbial reduction than the rinse cycle. Furthermore, the antimicrobial impact of detergents was greatest at the lowest AUC values (i.e., during short cycles). Taken together, our results suggest that the applied chemistry may help to enhance antimicrobial performance especially in short dishwashing cycles. Full article

Maintaining quality of life through functional autonomy is crucial for supporting aging in place. While assistive technologies and architectural adaptations have received significant attention, there is limited knowledge on how older adults independently adapt domestic routines using everyday household products. Background/Objectives: This study aimed to explore how functionally independent older adults manage key domestic tasks and to identify user-driven adaptations that could inform inclusive product design. Methods: We conducted a qualitative field study involving non-participant observations and in-depth case studies with 20 older adults aged 65–85 living in urban Chile. Participants were observed while performing cooking, dishwashing, and waste disposal activities. Thematic analysis and axial coding, based on grounded theory principles, were applied to identify adaptation strategies and usability barriers. Results: Participants employed a range of adaptation strategies across tasks, including temporal redistribution of effort, spatial reorganization, informal tool use, and reliance on social support. These adaptations reflected creative and situated responses to physical and environmental constraints. Many strategies could be interpreted as emergent user solutions, offering practical insights for the inclusive and low-cost redesign of everyday objects. Conclusions: Older adults actively modify their interactions with domestic environments to preserve autonomy and functionality. Recognizing and incorporating these emergent user adaptations into product design processes can strengthen inclusive design practices, support aging in place, and inform public health strategies aimed at promoting independence among aging populations. Full article

Global water scarcity is becoming an increasingly critical issue; greywater reuse presents a promising solution to alleviate pressure on freshwater resources, particularly in arid and water-scarce regions. Greywater typically sourced from household activities such as laundry, bathing, and dishwashing, constitutes a significant portion of domestic wastewater. However, the reuse of greywater raises concerns about the potential risks posed by its complex composition. Despite the growing body of literature on greywater reuse, most studies only focus on specific contaminants, thus there is a limited understanding of the comprehensive profile of contaminants, health, and environmental effects associated with these pollutants. This review adds new knowledge through a holistic exploration of the composition and physico-chemical characteristics of greywater, with a focus on its organic and inorganic pollutants, heavy metals, EDCs, emerging microplastics, nanoparticles, and microbial agents such as bacteria, fungi, viruses, and protozoa. This review sheds light on the current state of knowledge regarding greywater pollutants and their associated risks while highlighting the importance of safe reuse. Additionally, this review highlights the removal of contaminants from greywater and the sustainable use of grey water for addressing water scarcity in affected regions. Full article

This paper presents a theoretical and experimental investigation into improving the energy efficiency of electrically heated systems through thermal energy recovery. Enhancing efficiency in such systems can significantly reduce energy consumption, operating costs, and greenhouse gas emissions, particularly when electricity is generated from fossil fuels. Commercial dishwashers are inherently energy-intensive due to the need for rapid and effective cleaning. Regulatory and market pressures increasingly encourage manufacturers to develop energy-efficient technologies. This study aimed to design, develop, and incorporate a miniaturized heat exchanger to recover waste thermal energy and reduce the overall energy consumption in a commercial dishwasher. In collaboration with Norris Industries, the University of Newcastle trialed a retrofitted internal heat exchanger in representative commercial dishwasher models. The device was designed to transfer heat from discharged wash water to preheat incoming freshwater. The heat exchanger was developed based on a theoretical thermal analysis and engineered for practical integration. Experimental testing demonstrated that the system achieved up to a 50% reduction in energy use without compromising the cleaning performance or increasing the manufacturing complexity. This approach offers a scalable and effective solution for enhancing energy efficiency in commercial dishwashing. Its broader implementation could substantially reduce the energy demand and greenhouse gas emissions across the sector. Full article

The usage of more than 30 billion straws a year has been reported in the European Union (EU), in 2020, one year before the official ban of single-use plastics in Europe. The impacts of this plastic waste on the environment and on our health are global and can be drastic. Since then, various alternative straws have emerged. This study assesses their effectiveness, primarily from an environmental perspective, to determine the best option among those available. Life-cycle assessment (LCA) was conducted using ReCiPe 2016 methodology and ISO 14040/44 standards, alongside a preliminary cost analysis and a consumer preference survey. The findings reveal that wheat straws demonstrated the lowest overall environmental impact, with a climate change contribution of only 0.0568 kg CO₂ eq. per year, while plastic straws showed the lowest cost at EUR 0.30 per year but contributed 0.084 kg CO₂ eq. Metallic straws, despite being reusable, had the highest washing-related emissions, with 85% of their annual impact (~0.169 kg CO₂ eq.) attributed to dishwashing. Paper and bioplastic alternatives showed up to 2.5 times higher climate impacts than plastic. Cost-wise, bamboo straws reached EUR 7.97/year, while silicone and metal straws were more economically favorable at EUR 1.17 and EUR 2.81, respectively. The consumer survey highlighted that 85% of users preferred traditional plastic straws, but 76% were open to reusable alternatives. From a socio-economic point of view, cost seems to play a minor role. However, consumers’ preferences towards the new products and their awareness of health and environmental risks are very significant factors affecting their approval of new alternatives and their displeasure towards traditional straw elimination. Full article

Many tasks in a modern household are performed by machines, e.g., a dishwasher or a vacuum cleaner, and in the near future most household tasks will be performed by smart service robots. This will relieve the residents, who in turn can enjoy their free time. This newly gained free time will turn out to cause the so-called spare time rebound effect due to more resource consumption. We roughly quantify this rebound effect and propose a CO₂-budget model to reduce or even avoid it. In modern industry, automation and AI are taking over work from humans, leading to higher productivity of the company as a whole. This is the main reason for economic growth, which leads to environmental problems due to higher consumption of natural resources. We show that, even though the effects of automation at home and in the industry are different (free time versus higher productivity), in the end they both lead to more resource consumption and environmental pollution. We discuss possible solutions to this problem, such as carbon taxes, emissions trading systems, and a carbon budget. Full article

Liquid jets impinging on surfaces are widely found in various industrial processes, such as spray painting, high-pressure water jets, and dishwashers. The liquid jets can break up into sprays with discrete, small-scale features that are difficult to reveal. This work proposes a multiscale solver in OpenFOAM that achieves two-way conversion by capturing the large-scale interface using the Volume of Fluid (VOF) approach and tracing small-scale droplets using the Discrete Phase Model (DPM). By comparing the VOF–DPM solver with the standard VOF solver, the conservation of mass and momentum, as well as the accuracy of the new solver are verified. Considering that, in spraying processes, collisions mainly occur after the liquid jet breaks up into multiple droplets, we simplify the model to focus on the collision of droplets with walls at different speeds and contact angles, corresponding to different materials. The results indicate that, as the speed increases, splashing becomes more likely and the droplets spurt further. It is also found that an increase of contact angle will increase the mean diameter of the discrete droplets. Overall, this multiscale solver can accurately capture both large-scale interfaces and small-scale droplets, offering wide application prospects. Full article

Background/Objectives: The dietary changes experienced by residents in long-term care facilities (LTCFs) following an earthquake are poorly understood. This study aimed to examine variations in nutritional status among residents of an Integrated Facility for Medical and Long-term Care (IFMLC), a particular type of Japanese LTCF, after the 2024 Noto Peninsula Earthquake. Methods: This descriptive study was conducted at the single IFMLC. A total of 115 residents living at the facility on 1 January 2024, at the time of the earthquake, were recruited for the study. The focus was the body weight and skeletal muscle mass changes observed before and after the earthquake. The observation period lasted for three months following the earthquake. Results: Water outage persisted for over a month, making dishwashing impossible and leading to an extended reliance on disposable dishes with limited capacity. This situation consequently reduced the variety and volume of meal options and overall energy intake meals. Residents’ body weight significantly decreased 3 months after the earthquake, and the prevalence of weight loss and skeletal muscle mass loss was particularly high in residents with normal swallowing function. To address nutritional deficiencies post-earthquake, the registered dietitian enhanced energy sufficiency through food fortification, oral nutritional supplements, and pre-prepared ready-to-hang liquid formulas. Conclusions: To prevent further weight and skeletal muscle mass reduction among IFMLC residents, providing ample water, and a disaster manual that can be used even with limited resources is essential. Furthermore, preparing for disasters by stockpiling foods and implementing strategies to enhance energy sufficiency is crucial. Full article

The brushless DC (BLDC) motor is crucial in a variety of industrial and consumer applications due to its efficiency and precise control. This study investigates the heat transfer and cooling mechanisms in liquid-cooled BLDC motors in dishwashers, which are fundamental to maintaining optimal operating temperatures. Elevated temperatures can reduce operational efficiency, emphasizing the importance of effective heat dissipation. Liquid cooling proves to be very effective and offers advantages over air cooling by providing even temperature distribution and more accurate temperature control. Integrating liquid cooling systems into dishwasher designs provides a viable solution for managing motor temperatures while preheating dishwashing water. Using existing water infrastructure, these systems dissipate heat generated during motor operation, increasing energy efficiency and reliability, as analyzed using computational fluid dynamics (CFDs). The aim of this study is to optimize thermal management strategies in BLDC motors, particularly in dishwashers, by filling a critical gap in the existing literature. The goal of this comprehensive analysis is to develop resistant and efficient cooling solutions tailored to dishwasher environments, ultimately extending the life of BLDC motors in home appliances while using heat transfer to preheat water for wash cycles. Full article

Image analysis is becoming increasingly popular in many industries. Its use is perfect for, among other things, assessing the quality of products on or off the production line. Highly automated, high-performance systems can be used for this purpose. However, there are situations in which automated vision systems cannot be used on the production line due to the specific nature of the process. One such situation is testing the resistance of paint applied to glass when washing in automatic dishwashers. It is carried out outside the production line, and typical production vision systems are not used here. An attempt was made to develop a cheap and easy-to-implement research method enabling quantitative measurement of paint loss on glass when testing the coating’s resistance to automatic washing. For this purpose, analysis of images taken during the study was carried out. The developed method is based on taking a series of photos of the tested object between each stage of the wash resistance test. The obtained photographic material is then analyzed by measuring the size of paint losses expressed in the number of pixels. Then, the percentage of paint loss is calculated. This method is cheap to implement and highly accurate. Statistical analysis of the results confirmed the method’s accuracy at 98%. Full article

This study aims to delve deeper into the relationship between the professional activities carried out in restaurant kitchens and some key air pollutants. The ultrafine particles (UFPs), nitrogen dioxide (NO₂), ozone (O₃), Total Volatile Organic Compounds (TVOCs) and formaldehyde (HCHO) indoor air concentrations were determined using real-time monitors. Simultaneously, the kitchen environment was characterized using video recordings with the aim to retrieve information pertaining to cooking, cookware washing and surface cleaning activities. Statistical analysis was carried out separately for the winter and summer campaigns. The obtained results confirmed that the professional activities carried out in restaurant kitchens had a significant impact on the concentrations of all the selected pollutants. Specifically, this study revealed the following key results: (i) indoor UFPs and NO₂ concentrations were significantly higher during cooking than during washing activities (e.g., about +60% frying vs. handwashing and dishwasher running), mainly in the winter; (ii) washing activity had a statistically significant impact on the TVOC (+39% on average) and HCHO (+67% on average) concentrations compared to other activities; (iii) some specific sources of short-term pollutant emissions have been identified, such as the different types of cooking and opening the dishwasher; and (iv) in some restaurants, a clear time-dependent relationship between O₃ and UFP, TVOC and HCHO has been observed, underlining the occurrence of ozonolysis reactions. Full article

The major problems related to environmental pollution are increasingly present among us. The uncontrolled use and incorrect disposal of products means that these problems are increasing at frightening rates. In this context, a major related problem is the incorrect disposal of dishwasher sponges that are no longer useful; their material being made up of petroleum derivatives causes this problem to be leveraged in the environment. In the present work, we evaluated and carried out tests in which these dirty sponges that would be discarded were used for the purpose of developing new sustainable adsorbent materials. These materials were washed and dried, crushed and made available for use, by which they were kept in contact with a paracetamol solution, evaluating the effect of mass, pH, kinetics, equilibrium, thermodynamic parameters, and cost analyses. The results demonstrated an adsorptive capacity of approximately 40 mg g⁻¹ and its cost was relatively viable, since this material would otherwise be discarded incorrectly. In conclusion, this material achieved the good removal of this studied contaminant and became an economical, viable, and ecologically viable material. Full article

As the regulations and consumer preferences in Europe tend to favor more energy-efficient household appliances, companies have to find innovative ways of saving electric energy during the operations of those appliances. One such method in dishwasher design is to reduce heat energy loss to the surrounding environment and reuse heat energy during the washing cycle, thus minimizing the time that heaters are operating. In this study, a numerical simulation involving computational fluid dynamics is implemented to speed up the iterative process of improving efficiency. The washing cycle has been simplified to include only the most critical moments of dishwasher work, and non-important components have been excluded. A workflow of simulations and numerical methods employed for this task is presented. The numerical simulations are compared with real-life experiments to assess their accuracy and verify boundary conditions. Geometric and washing cycle improvements are compared with the base design and show satisfactory results. Full article

This manuscript explores the relationship between the economic awareness (as a part of energy awareness) of Polish households and their sustainable energy consumption practices. Sustainable consumption is measured by the frequency of behaviors such as turning off electrical devices when not in use, removing mobile device chargers from sockets, switching off lights when leaving a room, preferring showers over baths, using washing machines and dishwashers only when full, and purchasing energy-efficient appliances and light bulbs. Economic awareness is gauged through variables such as knowledge of electricity tariffs, understanding of electric bill components, awareness of electricity prices, exact knowledge of electricity expenses, electricity usage in kWh, knowledge of effective energy-saving methods, and familiarity with the energy efficiency classes of appliances and light bulbs. This study presents profiles of households with high and low economic awareness regarding their electricity expenditures and examines how these profiles differ in their sustainable energy consumption behaviors. This research is based on a survey of 1407 Polish households conducted online in 2023. Data collected from the survey were subjected to statistical analysis and are presented in tables and graphs. The findings are discussed in the context of the existing literature in the field, highlighting the implications of economic awareness on sustainable energy consumption practices. This research contributes to understanding how economic knowledge influences energy-saving behaviors among Polish households, providing insights for policymakers and energy conservation initiatives. One of the key findings of this paper is the significant association between economic awareness, energy-saving knowledge, and the adoption of sustainable energy consumption behaviors among Polish households. This study reveals that households with higher levels of economic awareness demonstrate a notably higher frequency of practices related to sustainable energy consumption compared to those with lower economic awareness. Similarly, households equipped with greater knowledge about energy-saving techniques exhibit a higher propensity to adopt energy-efficient behaviors. This underscores important roles of economic literacy and education in fostering behavioral changes towards more sustainable energy practices, highlighting the importance of targeted interventions and educational campaigns aimed at enhancing economic awareness and promoting energy-saving knowledge among consumers. Full article