Application of compact heat exchangers in refrigeration and air conditioning appliances are beneficial to reduce the sizes and to improve the performances. The objective of this paper is to summarize the recent developments of the following typical compact heat exchangers. The introduction to plate heat exchangers covers the advances in high efficient plate type, new flow channel, and their usages as economizers. The introduction to printed circuit heat exchangers covers the manufacturing method, flow channel design as well as the heat and flow characteristics. The illustration on the insert-plate microchannel heat exchanger covers the structure as well as its performance advantages over conventional microchannel heat exchangers. The structure and application fields of micro bare-tube heat exchanger is also introduced.

During the operation of the compressor, part of the heat is lost through the casing through convection and conduction in the surrounding environment. This part of the heat can be used to defrost air-cooled refrigerators and heat pump evaporators; refrigerator food thaw; heat pump unit for enhanced heating, etc. When the refrigeration system is operating, a large amount of condensation heat is discharged into the environment, causing waste of energy, increasing the ambient temperature, and reusing the condensation heat can not only reduce environmental heat pollution, but also an energy-saving method that turns waste into treasure. The use of condensation heat mainly includes defrosting of air-cooled refrigerators and heat pump devices; heating of domestic water and production of hot water, etc. The waste heat utilization of refrigerators and heat pump systems is an energy technology research, and the energy-saving benefits can be effectively realized on the basis of rational use of energy.

Refrigerator and room air conditioner and other small refrigeration and air conditioning devices are widely used, it is necessary to analyze the current technical status and development trend of the small capacity fully enclosed compressors. This paper combines mainstream products of reciprocating compressor, rotor compressor and linear compressor in the household market, briefly introduces the current technical status of these three types of compressors, and forecasts its future technological development.

The development of air-conditioner converter technology makes it possible to use advanced control methods to save energy. In this paper, the energy-saving principle of variable-frequency operated air-conditioners and related control methods including segmentation fixed point control, PID control, and intelligent control methods represented by fuzzy logic control, are presented. The reason why these methods were energy-saving was that variable-frequency operated air-conditioners avoided the energy loss caused by the frequent on-off versus fixed frequency air-conditioners. However, the energy-saving potential of variable-frequency air-conditioners was far beyond this. With reference to those of central air conditioning systems, the control methods based on air-conditioner models and human comfort which could fulfill the energy-saving potential of variable-frequency air-conditioners were introduced. Finally the control methods based on data reflecting human thermal feeling instead of merely return temperature were described.

In this paper, the relationship between superheat of oil temperature and dilution of lubricating oil in compressors with low pressure chamber and high pressure chamber is put forward through theoretical research on the dissolution characteristics of refrigerant and lubricating oil. The experimental data between superheat of oil temperature and wear of compressors with low pressure chamber and high pressure chamber are obtained through experimental research, and the compressor is prevented in order to ensure the whole compressor of air-conditioning heat pump unit. The criterion of wear and tear provides technical support for enriching and perfecting the product standard of air-conditioning heat pump units in the future.

In this paper, the factors affecting the air volume of wall-mounted air conditioning indoor unit are summarized. Fluent software is used to simulate and analyze the problem of low air volume in a wall-mounted air conditioning indoor unit, and some suggestions are put forward to improve the performance of air deflector and cross-flow vane. The improved scheme is tested and verified in practice, which provides a solution to this kind of problem.

Aiming at reducing the temperature of the electrical of air conditioner outdoor unit, the thermal analysis software was used to simulate the temperature field for air conditioner outdoor unit. According to the temperature distribution in the space where the electrical was located, a scheme was proposed that the opening was added to the bulkhead of the air conditioner outdoor unit, compared with the bulkhead without opening scheme. The results showed that the new scheme increased the air flow and reduced the temperature of the electrical well, the temperature of the electrical was reduced by 12.3℃ on average. Finally, the new scheme were verified by experiments, the results showed that the simulation was valid and reliable.

Appropriately increasing the flexibility of the piping can reduce the stress and strain of the piping and prevent leakage of the piping. The traditional method of improving the flexibility of piping is to increase the U-shaped pipe, but excessively increasing the U-shaped pipe not only increases the cost, but also makes the fixed frequency of piping system concentrated and increases the difficulty of keeping away the operating frequency of the compressor. Based on this, a flexible design method of air conditioning piping was studied, and the flexibility of piping was simulated and analyzed to realize the quantitative evaluation of piping flexibility. Finally, the design method was verified by stress and strain testing. The results show that the flexible design method of air conditioning piping based on CAE has higher credibility, which can make a preliminary judgment on the advantages and disadvantages of piping, and provide reference for air conditioning piping design.

With the rapid development of intelligent home appliances, refrigerators with storage in addition to the basic role of the ingredients, it can also manage people's diet, and to be associated with people's health. This article describes the application of smart refrigerator health management system, to provide users with Personal Tailor diet more personalized recommendations, including hardware design and software design process and gives some examples of data and UI interface of health management , at the same time health monitoring for one of the major parameters of the pulse wave simulation and description of the relationship is another important parameter oxygen saturation and health were discussed, further illustrates the importance of finger pulse detection.

To investigate the effects of different storage methods on the quality of rice, the main physicochemical characteristics as the index, we carried out different storage methods of 5℃, 85%RH and 25℃, 60%RH and 32℃, 85%RH on the quality of rice. The results showed that the storage method of 5℃, 85%RH and seal could better inhibit the increase of fatty acid value and amylose content in rice. This method could better keep sense quality and maintained the storage quality of rice.

In the case of external magnetic field, a series of physiological changes occur in the food material. The main mechanism is that the magnetic field changes the binding state of enzyme with water, also the magnetic field can affect the electron transfer in the respiratory metabolism of fruits and vegetables, which directly results in the decrease of respiratory metabolism, Magnetic field will lead to disturbance of microbial metabolic activity, reduce the corruption of food materials, and achieve the effect of keeping fresh. achieve the preservation of fruits and vegetables. In this paper, the influence of magnetic field technology on fruit and vegetable preservation was studied by using refrigerator as carrier, finally confirm the best condition of the magnetic field.

Based on the explicit dynamics theory, this paper analyzes the drop simulation of the refrigerator and proposes an optimization scheme. According to the relevant standards, the simulation analysis was carried out for the two conditions of the refrigerator falling and the rear corner falling. The simulation results show that when the refrigerator is dropped using the original package bottom pad, the foaming leg stress of the refrigerator is greater than the yield limit of the material, and the deformation of the compressor bottom plate reaches 10.7mm exceeding the allowable range of the test standard. Test results show that the original package bottom pad cannot pass the drop test. Combined with simulation analysis and dynamics related theory, an optimization scheme for packaging bottom pad is proposed. The simulation results of the bottom pad optimization scheme show that the drop impact acceleration, foaming leg stress and compressor floor deformation are smaller than the original drop data. The test proved that the bottom pad optimization scheme passed the test.

The packaging base of household electrical appliances has long been used in combination with foam or cardboard or foam and paper corner protector. It not only has high cost, low production efficiency, but also has poor waterproof and impact resistance. It needs to bring forth new ideas and replace traditional forms. This time we combine plastic film and foam to achieve integrated production, procurement and transportation. The feasibility is discussed through the study of manufacturing process, performance analysis and key indicators.

This paper systematically introduces the horizontal transportation of refrigerators, emphatically analyses the design of packaging system, test verification method and loading and unloading rules of horizontal transportation, and points out that horizontal transportation is the inevitable trend of logistics transportation.

The problem of hazardous waste disposal has been paid more and more attention by the state, enterprises and the public. Because of its production characteristics, the emergence and disposal of hazardous waste has its particularity in the electronic industry. On the basis of communication and investigation with member enterprises, this paper combs the problems reflected by industry enterprises, hoping to help the continuous improvement of policy, hazardous waste management and the healthy development of hazardous waste treatment industry.

In China, the popularity of air cleaners was mainly caused by the deteriorated haze problem and the universal of PM2.5 concept in recent years^[1]. Chinese air cleaners standard was drafted in the last decade. Until the past ten years, a relatively integrated system of air cleaners standard was built in China, while South Korea standard "Indoor Air Cleaner" as early as in 1998 drafted by the association of South Korean air purification and standards review committee. Air cleaners are widely applied in general South Korean family. Therefore, Korean users have strict requirements on the quality of the air cleaners and filters. According to the survey, in China, none of the testing institutions has been authenticated on South Korea "Indoor Air Cleaners" standard testing capacity so far. In this paper, the south Korean SPS-KACA002-132: 2018 "Indoor Air Cleaners" standard is interpreted, and the establishment process is introduced.

In the current switch power supply design of household appliances, NTC resistance has become a very important component in the power supply input circuit design to suppress the surge current. It is very important to choose a suitable NTC resistor for switching power supply with power over 10W. For switching power supplies over 10W, it is not suitable to print the transient surge current with a resistor with a fixed resistance value due to the heating and power consumption problems. Therefore, many companies choose NTC resistor to print the transient surge current.In order to effectively solve the damage of surge current and surge voltage at the moment of power on to the back stage of power supply, this paper discusses the function of NTC resistance value and position in the input loop.

With the expansion of the scale and influence of the high-end women's wear market, consumers' demand for high-end clothing is increasing. Due to the complex features of materials, tissue structure parameters and color, reasonable washing care methods are also urgently required. We investigate and extract the care labels of garments to analyze the washing care methods to analyze the fabric composition and pattern of high-end garments suitable for machine washing, hand washing and dry cleaning. Then we conduct statistics and analysis on the composition of these high-end women's fabrics and patterns. Finally, the relationship between the information marked by the high-end women's toiletries label and the clothing characteristics is analyzed.

In order to meet some special area wide input voltage range requirements of the home appliance controller, through using the auxiliary power of the flyback switching power supply to over voltage detection circuitry. Design a low standby power flyback switching power supply with input range of 70VAC~300VAC, The test result shows that when the input voltage range is 70VAC~300VAC, the two circuit output voltage fluctuation can be controlled within 2%, the ripple can be controlled at 100mV, and the noise can be controlled at 200mV. And the whole control system standby power can be reduced by about 0.3W, the facts show that the design is feasible and effective.

In this paper, a new type of water flow switch structure is designed, in which a protective sleeve is added to the target to prevent impurities from entering the water flow switch shell. At the same time, the anti-fatigue strength of the target can be increased by increasing the maximum chamfering Angle of the target and increasing the reinforcing bars on the target. Experiments show that the new water flow switch can effectively prevent impurities from entering and increase the fatigue strength of the target.

There are many problems in the artificial grading of the flatness of fabric appearance. The fast and accurate objective grading method is urgently needed in the market. This paper construct the fabric appearance flatness image acquisition device, after the construction, the device can achieve illumination uniformity of 88%, image uniformity of 93.73% and the collected fabric image wrinkles are clear, which can meet the requirements of objective evaluation method of fabric flatness.

Large flow reverse osmosis (RO) water purifier, in order to better meet the smaller installation space under the kitchen cabinet, the flat filter bottle instead of the cylindrical filter bottle, so that the shape of the water purifier becomes slim. In the process of product development, it is difficult to verify its reliability. Usually, the method is to make the product into a mold sample and then verify it, which requires more money and time. However, the FEA technology can overcome the shortcomings of the above traditional product development. When designing flat filter bottles, we use FEA simulation analysis to find the weak points of the product and optimize them through the total deformation and the stress intensity. In this way, the flat filter bottle can be reliably applied to the water purifier product.

This paper analyses the effect of the main parameters in the washing, rinsing, spinning and drying stages of the drum washing machine on its washing and drying performance. And the development directions of washing and drying technologies are also prospected.