Research on suppression of 6th order frequency noise in outdoor unit compressorsAbstract:For a specific outdoor unit model experiencing abnormal noise at the 6th harmonic frequency during heating operation,subjective evaluation indicated failure.Through quasi-steady-state compressor frequency sweep testing,along with modal and modal strain energy analysis of the compressor piping system,it was determined that the 6th harmonic exceedance was caused by structural resonance of the liquid receiver.An optimized solution involving reinforcement of the liquid receiver welded bracket was proposed to enhance connection stiffness and natural frequency.Experimental testing demonstrated that the optimized solution achieved a 19 dB reduction in peak noise level at the 6th harmonic compared to the original design.The abnormal noise was eliminated,and subjective evaluation results were favorable.
Study on influencing factors of the natural frequency of accumulator structuresAbstract:To address the noise issue caused by resonance excitation of the natural frequency in accumulator structures,investigates the influencing factors of natural frequency in accumulator structures.Based on single-degree-of-freedom system theoretical analysis,the natural frequency is primarily determined by the structural"stiffness"and"mass".A finite element numerical simulation model was established with less than 5%error between theoretical calculations and experimental measurements.Characteristic dimension sensitivity analysis reveals that bracket feature dimensions primarily affect the upper natural frequency:increasing bracket thickness,width and height enhances bracket stiffness and raises the upper natural frequency,with sensitivity ranking:bracket thickness>bracket width>bracket height.Bend and cylinder wall thickness dimensions mainly influence the lower natural frequency:increasing bend wall thickness,reducing bend length and thinning cylinder wall thickness improve bend stiffness and reduce cylinder mass,thereby increasing the lower natural frequency,with sensitivity ranking:bend wall thickness>bend length>cylinder wall thickness.In a practical case study with largely finalized product structure,thickening the bend wall thickness—a minimal structural modification—effectively adjusted the natural frequency and resolved the accumulator noise issue.
Research and application of intelligent control dual-power enhanced heat dissipation technology in microwave ovensAbstract:Modern micro wave ovens,in addition to basic micro wave heating,integrate multiple cooking functions such as steaming,boiling,baking and air frying,aiming to provide users with a more convenient and diverse cooking experience.During the operation of a microwave system,the magnetron generates a large amount of heat by converting electrical energy into magnetic energy.In addition,the internal electronic components(such as amplifiers)consume electrical energy and convert it into thermal energy when working.Excessively high temperatures may lead to a decline in equipment performance or even damage.Therefore,effective heat dissipation is crucial for ensuring the normal operation of microwave equipment and has become one of the important demands in the industry.To this end,by leveraging artificial intelligence solutions,an innovative intelligent control dual-power enhanced heat dissipation technology was designed.The heat dissipation system was optimized from a single air duct to a dual air duct,and a digital model of microwave working condition temperature rise was established.CAE simulation calculations were carried out to continuously verify and optimize,achieving a dynamic balance among the energy input to the microwave oven,the food absorption capacity,and the heat dissipated from the residual heat,effectively improving the working condition temperature rise.The temperature has been reduced from the original 78.49 ℃ to 68.50 ℃,improving the quality of cooked food and increasing the cooking efficiency by 21.9%.This ensures that the temperature during the combined cooking operation of the microwave oven is controlled within a reasonable range,thereby extending its service life and ensuring usage safety.
Energy efficiency optimization analysis of room air conditioner with refrigerant R290Abstract:Although there are already products on the market using R290,there is room to improve its annual performance factor(APF).Optimizes the heat exchange system of a 1.5-horsepower R32 household wall mounted air conditioner using R290 refrigerant as substitute to improve its energy efficiency through simulation and experimentation.Firstly,the optimal refrigerant filling amount was tested.The results showed that the system had the best performance when the filling amount was 300 g,with APF of the system reaching 4.812,and the filling amount met the maximum filling amount requirements of the specifications.Secondly,through testing,it was found that when replacing R32 with R290 refrigerant,there were two aspects that need special attention due to different characteristics of the refrigerants:(1)R290 refrigerant had higher requirements for the distribution effect of the distributor,and the problem of uneven distribution in the heat exchanger could be greatly improved by optimizing the distributors of internal and external unit;(2)R290 refrigerant was sensitive to pressure drop.By eliminating the subcooling section and replacing the connecting pipe,the system pressure drop could be effectively reduced.The APF of the prototype increased by 5.84%after optimization,reaching first level of the energy efficiency of national standard.
Experimental study on exhaust temperature protection control for air conditioner compressorsAbstract:To address the issue of frequency oscillation in variable-speed air conditioners caused by elevated discharge temperatures under high ambient and high compression ratio conditions,a compressor frequency control framework is developed.The framework introduces a dynamic discharge temperature threshold and target frequency mapping based on risk levels,integrates rate limiting and anti-windup compensation in the speed regulation loop,and establishes a coordinated control and parameter tuning procedure that balances discharge temperature regulation with actuator rate and amplitude constraints.Experimental results show that,compared with conventional fixed-threshold logic,the proposed method reduces the frequency oscillation amplitude from±10 Hz to±2 Hz~±4 Hz,significantly shortens protection activation and recovery times,and mitigates fluctuations in airflow and room temperature while improving overall energy efficiency.Without any hardware modification,the proposed framework effectively enhances system stability and operational efficiency.
Multi-field coupled modeling of magnetic components:from electrical losses to thermal performance predictionAbstract:Investigating the temperature distribution patterns and electrothermal conduction mechanisms of magnetic components during operation holds significant theoretical and practical value for optimizing device design and enhancing system reliability.Focus on the temperature rise of magnetic components in household variable-frequency air conditioning electric control systems.Based on the electrical characteristics of magnetic elements and their loss mechanisms,establish a multi-physics coupled simulation model integrating electrical,magnetic,loss,and thermal fields to systematically analyze the electrothermal coupling process from electrical parameters to temperature distribution.Furthermore,numerical simulations and analysis are conducted to examine the temperature rise characteristics and distribution patterns of PFC inductors.The results demonstrate that coupling the electrothermal process through component loss calculations can effectively predict the thermal behavior of magnetic devices,providing a reliable theoretical foundation and technical support for design optimization and addressing excessive temperature rise issues.This approach establishes a technical basis for board-level electrothermal co-design in thermal management,thereby reducing development costs.
The application of PET in transparent parts of refrigeratorsAbstract:At present,the transparent interior parts of refrigerators are mostly injection-molded with GPPS,and the cracking of these parts during transportation and use has become a major economic loss in the refrigerator industry.Focused on exploring the possibility of using PET material,which had better anti-cracking ability,to replace GPPS in the production of transparent interior parts for refrigerators.By comparing the key properties of PET and GPPS,the superior anti-cracking performance of PET was highlighted.Furthermore,the SWOT analysis matrix was used to demonstrate the potential opportunities and challenges of applying PET material in refrigerator transparent interior parts.Practical examples were provided to illustrate the issues and precautions to be aware of when designing and producing PET transparent interior parts for refrigerators.Finally,based on the market feedback of a certain refrigerator model that had switched to PET material,the quality improvement and economic benefits brought by using PET material were summarized.
Research on multi-nozzle jet-based wall-mounted air conditioners' comfortable airflowAbstract:People's demands for a higher quality of life are increasing in the post-epidemic age,and they are becoming increasingly conscious of the comfort of indoor air.The health and comfort features of household air conditioners have gained significant attention in recent times,making them popular choices for air conditioning.Conventional air conditioners frequently have a mechanical air supply,cool directly with cold air rushing in,a heating head is hot while the feet are cold,and poor human comfort.The double-walled multi-spout air deflector is a new type of air guide plate that this paper proposes.It is designed using the multi-jet nozzle jet principle and diffuser principle as its foundation.To optimize the splash type interference soft wind deflector,different air guide plate porosity,soft air ring porosity,air outlet shape,and soft air ring spacing were used in the organization of the airflow numerical simulation using Fluent software.Through a comparative analysis of wind speed distribution,end face air volume,turbulence intensity,and other parameters,the best air comfort soft wind ring guide plate program was evaluated.Finally,the air comfort test was conducted to confirm the soft wind effect of the soft wind ring guide plate.According to the findings,the splash type interference soft wind deflector can effectively reduce wind speed in the area of human activity,realizing the effect of soft wind,and enhancing user experience.It can also lessen the sense of blowing while maintaining the air conditioner's cold volume and wind volume without affecting the air conditioner's normal cooling and heating of the air supply range.
Research on the application of intelligent optimization control technology in enhancing the cooking performance of steam ovensAbstract:With the improvement of living standards,more and more users have purchased steam ovens that bring a lot of convenience and culinary pleasure.At the same time,while people are enjoying delicious food,steam oven also bring about some pain points such as the grilled meat becoming tough,burnt and the oil stains being hard to clean.To this end,by applying the optimization theory and building a digital technology model,the method of finding the optimal solution under given conditions is explored.The intelligent optimization control technology for steam ovens is innovated.Through precise algorithms,multiple factors such as temperature,humidity,and heating time during the cooking process are intelligently controlled for cooking verification and iterative optimization.Realize the iterative upgrade of cooking methods such as"dual control of temperature and humidity for fresh steaming,self-controlled maturity,and high-temperature self-cleaning of oil stains",achieving the best cooking effect of deliciousness and texture.Effectively address the pain points of meat texture being tough and fat being difficult to clean for users,and enhance the level of user experience reputation.
Research and discussion on testing method of freezing point of test package for refrigeration appliancesAbstract:An accurate measurement method based on thin wire thermocouple is proposed to solve the problem of lack of measurement method for freezing point temperature of test package in performance test of refrigeration appliances.By comparing the measurement results of platinum resistance and thermocouple,it is found that platinum resistance is easily disturbed by the environment because of its size,and the thin-wire thermocouple can significantly reduce the data deviation when it is arranged in the geometric center of the test package,which is more suitable for measuring the freezing point temperature.The method of determining the stable condition in the freezing process is clarified,and it is suggested that the stable condition of temperature fluctuation limit per unit time should be used to screen representative data,and the freezing point temperature should be obtained by calculating the average value.In addition,it is proposed to correct the measurement results based on the freezing point of pure water to eliminate the influence of equipment and environmental factors and ensure the comparability of cross-laboratory data.Experiments show that this method can effectively improve the accuracy of freezing point temperature of test packages,and provide technical support for standardization and reliability of refrigeration appliance testing.
Application analysis and optimization of refrigerant radiator in VRFAbstract:In VRF air conditioning system,efficient heat dissipation directly determines the overall performance and compactness of the machine.Compared with traditional finned heat exchangers,refrigerant radiators are increasingly becoming the preferred choice for electronic control modules,especially IPM cooling solutions,due to their excellent heat dissipation efficiency,stable heat dissipation performance,and low sensitivity to environmental temperature changes.To accurately quantify its performance,conducted an in-depth analysis of a refrigerant radiator applied to practical products through a combination of theoretical modeling and experimental testing,measured the overall thermal resistance of the refrigerant during cooling,revealed the distribution of its internal thermal resistance through measurement.Based on this data,propose three optimization schemes,which provide reference technical paths for the design of next-generation high-power density and high reliability multi split products.
Indoor formaldehyde emission characteristics and evaluation of formaldehyde removal efficiency of air conditionerAbstract:Indoor formaldehyde pollution poses a serious threat to health,urgently requiring efficient control.Air conditioning systems integrated with formaldehyde removal functions,leveraging their advantages of wide coverage and high frequency of use,serve as an ideal platform for the synergistic regulation of temperature,humidity,and air purification.This paper systematically reviews the sources and long-term release characteristics of indoor formaldehyde.The principles,effectiveness,and limitations of mainstream formaldehyde removal technologies integrated into air conditioners were critically examined.Moreover,the constraints on actual performance imposed by dynamic environmental parameters,complex pollution sources,system compatibility,and user requirements were analyzed.Finally,the key direction of aldehyde removal technology upgrading is prospected,which provides guidance for the research and development of the next generation of efficient and intelligent purification solutions.
Research on the application of the CARE interaction model in smart home appliance customer service systemsAbstract:With the widespread adoption of smart home appliances and the trend toward fully interconnected homes,users' demands for seamless device interaction and enhanced after-sales customer service have significantly increased.However,traditional customer service models have long faced challenges such as insufficient intelligence and fragmented user experiences.To address these issues,proposes and reviews the innovative application of the CARE interaction model—integrating human-computer interaction and intelligent technology in smart home appliance customer service.The CARE model comprises four key dimensions:Comprehension,Agent,Rapport,and Ensemble UI,emphasizing deep understanding of user intent,autonomous agent capabilities,empathetic human-like interactions,and unified multimodal interface designs.Firstly,introduces the context and background of intelligent customer service within the home appliance industry,followed by the theoretical foundations and framework of the CARE model.It then elaborates on each design dimension with comparative analysis and summarizes typical application strategies and practical implications of the model in the industry.The research indicates that the CARE interaction model effectively enhances the humanization and intelligence of smart customer service.Furthermore,by integrating large-scale AI models and interdisciplinary design methodologies,the CARE model will play an increasingly pivotal role in shaping innovative customer service solutions within the home appliance sector.
A survey on the evaluation of intent understanding in smart home voice interactionAbstract:With the integration of artificial intelligence(AI)and the Internet of Things(IoT),smart home voice interaction is evolving from functional command execution to demand understanding and proactive service.Intent Understanding is the core of this service,and its evaluation system is crucial for measuring voice assistant performance and user experience.Reviews the current status of evaluation for intent understanding in smart home voice interaction,systematically summarizing its technical evolution,datasets,and metric systems.Addressing existing limitations,it identifies three major challenges:difficulty in quantifying intelligence,insufficient coverage of complex interactions,and lack of corpus standardization.Further envisions a human-centered evaluation framework guided by user experience and emotional intelligence.Also puts forward three construction paths:standardizing data and scripts,unifying metrics and reporting protocols,and validating transferability between simulation and real-world scenarios,providing a reference for achieving human-centric intelligence evaluation.
Optimization of low-frequency band conducted disturbance voltage in voice-controlled air conditionersAbstract:With the improvement of living standards,household appliances have increasingly rich functions,and electromagnetic compatibility(EMC)has become a key design indicator.As a widely used household appliance,the electromagnetic compatibility performance of air conditioners directly affects their operational reliability and the degree of interference with other devices.Taking the electromagnetic interference(EMI)problem of the switching power supply of variable frequency air conditioners as the research core,analyzes its generation mechanism,and proposes optimization solutions.Research shows that the high-frequency switching devices in the switch power supply generate differential and common-mode noise during rapid switching,and the loop design of the power circuit,the leakage inductance of the transformer,and parasitic parameters are the main sources of interference.Through theoretical analysis and experimental verification,the following suppression measures are proposed:optimized design of the transformer,circuit improvement,shielding and layout optimization.In a case of a voice air conditioner with 600 kHz~700 kHz conducted interference exceeding standards,experiments found that the design defect of the transformer shielding layer was the main cause of interference.By optimizing the shielding structure,the peak noise was significantly reduced,verifying the effectiveness of the solution.The research results provide practical guidance for the EMC design of air conditioners and emphasize the importance of reducing interference from the source.
Application and research of smart home appliance integration for elderly healthcare based on multi-agent systemAbstract:With the intensification of global population aging,the demand for elderly healthcare is increasingly urgent.Traditional health monitoring systems rely on wearable devices or single-point sensors,facing issues such as low compliance,data isolation,and poor user experience.Proposes an AI-driven multi-agent healthcare system in smart home environments,utilizing smart appliances(e.g.,refrigerators,mattresses,toilets)as behavior-sensing nodes to collect real-time behavioral data(e.g.,usage frequency,pressure distribution,toileting patterns).The system employs the LangGraph framework for multi-agent task coordination,integrating modules for health monitoring,device control,and behavior understanding,while analyzing health trends through expert rules and machine learning.By leveraging the"appliance-as-sensor"concept and user-friendly notification mechanisms,this system significantly enhances elderly user experience and addresses accessibility and privacy concerns,offering a novel solution for integrating smart homes with elderly care.
Research on the optimization of defrosting control based on the principle of hot air defrostingAbstract:An optimized defrosting control method based on the principle of hot gas defrosting is proposed to address the issues of reduced heating efficiency and operational stability caused by frost formation in heat pump air conditioners under low-temperature,high-humidity conditions.Compared to existing shutdown defrosting technologies,the hot gas defrosting technique significantly reduces system energy consumption and enhances indoor comfort by maintaining the four-way valve in a fixed position and optimizing the opening of the electronic expansion valve.Analyzed the effects of indoor fan airflow,outdoor fan speed,and compressor frequency on defrosting performance through psychrometric chart analysis and experimental validation.The results indicate that reducing the indoor fan speed can extend the defrosting duration by 14%to 40%and increase the outdoor unit coil temperature by 0.7 ℃;when the outdoor ambient temperature is above 0 ℃,activating the outdoor fan can utilize atmospheric heat sources to assist in defrosting;reducing the compressor frequency is more beneficial for defrosting performance,but indoor heating comfort should be considered when adjusting the above control parameters.
Research on operating noise prediction model of range hood based on multi-parameter fittingAbstract:To address the challenge of predicting the noise of range hoods,a research method combining experiments and simulations is proposed.Taking a top-suction range hood as the research object,three different combinations of air cabinets and impellers are selected for the study.Noise measurements under different operating conditions are carried out within the rotational speed range of 900 r/min~1600 r/min to collect noise data.The analysis reveals that the air volume Q,power P,and operating noise Lw satisfy a multivariate logarithmic function relationship,and the final relational expression Lw=k1+k2·lg(Pk3·Qk4)is proposed.
Research on the transformation and upgrading of China's home appliance industry under the dual carbon contextAbstract:Under the"dual carbon"goals,systematically examines the current status,challenges,and countermeasures of low-carbon transformation in China's home appliance industry.Industry data from 2024 shows that the main business revenue of home appliances reached 1.95 trillion yuan,with production rebounding but carbon emissions remaining a prominent issue.Corporate carbon emissions exhibit a divergent trend:for instance,Haier Smart Home reduced its emissions by 23.86%in 2023,while TCL and Midea saw increases exceeding 50%.The industry faces challenges such as reliance on energy structure,insufficient technological innovation,and weak supply chain collaboration.Both domestic and international experiences indicate the need for policy guidance and technological innovation to drive transformation.Domestic research primarily focuses on technological innovation,environmental regulations,and industrial chain collaboration.Recommendations include:strengthening R&D in energy-saving and emission-reduction technologies,optimizing the energy structure,and striving to achieve zero growth in manufacturing sector carbon emissions by 2030;improving the carbon trading market by expanding coverage and enhancing carbon price effectiveness;enhancing talent cultivation,promoting technological transformation,and industrial upgrading;expanding green foreign trade to elevate value chain status.
Development trends of intelligent refrigerator food management functionsAbstract:With the rapid development and deep integration of Internet of Things(IoT),artificial intelligence(AI),big data,and cloud computing technologies,smart homes are transitioning from single-product intelligence to a new stage of whole-scene intelligence.As the core hub of the smart kitchen and a key node in family health management,the value of smart refrigerators has far surpassed traditional refrigeration and preservation functions.Their core competitiveness is increasingly focused on the intelligence level of food management capabilities.However,the isolated development of food recognition technology alone does not support the vision of smart refrigerators as the"family health management hub."By systematically exploring the evolution of food management functions in smart refrigerators,this study analyzes the core development trends from technical,functional,and ecological dimensions,aiming to provide new directions and insights for the overall development of the smart refrigerator industry.