Radiant heat dissipation coating for air conditioning heat exchange tubes

Under the trend of cost control and lightweighting in the air conditioning manufacturing industry, aluminum tubes are gradually replacing copper tubes in core heat exchange components such as evaporators and condensers. However, the inherent low infrared emissivity and poor heat transfer efficiency of aluminum substrates result in a gap in energy efficiency and stability between aluminum tube air conditioners and copper tube products. ZS-411 developed by Beijing Zhisheng Weihua Chemical Co., LtdRadiant heat dissipation coating for air conditioning heat exchange tubesBy strengthening radiation heat transfer and protective empowerment, the performance defects of aluminum tubes can be effectively compensated for. Through actual testing and verification, the coated aluminum tube heat exchanger can rival copper tube products in terms of heat transfer efficiency and energy-saving effect, providing new ideas for balancing cost and performance in the air conditioning industry.

ZS-411Radiant heat dissipation coating for air conditioning heat exchange tubesMaterial toCarbon nanotubesSpinel metal oxide is used as the core heat dissipation filler, supplemented with rare earth element oxide to optimize performance. It is prepared using a high-performance heat dissipation film-forming solution and solidified to form a dense coating that combines high radiation heat transfer and strong protective functions. The empowerment mechanism for aluminum tube heat exchangers is mainly reflected in the following three aspects:

1. Strengthen radiative heat transfer to compensate for the performance shortcomings of aluminum tubes

At 300K, the hemispherical infrared emissivity of the coating reaches 0.92, and the core radiation band covers 0.76-13.5 μ m (matching the atmospheric window), which can increase the infrared emissivity of the aluminum tube surface from 0.5 to above 0.92. By enhancing heat exchange through passive infrared radiation, it is possible to accelerate the outward radiation and cooling of heat when the condenser temperature is higher than the environment, and to improve the heat absorption efficiency during the evaporator heat absorption stage, forming a triple high-efficiency heat exchange system of "conduction+convection+radiation", directly compensating for the insufficient thermal conductivity of aluminum tubes.

2. Strong anti-corrosion self-cleaning to ensure long-term stable operation

After curing, the coating forms a dense ceramic coating, which can effectively block the contact between corrosive media such as moisture, dust, and oil fumes and the aluminum tube substrate. After testing, its salt spray resistance performance reached 4000 hours without any abnormalities, and it can reduce the corrosion rate of aluminum tubes by more than 90% in high humidity and dust environments. At the same time, the coating has low surface energy and excellent hydrophobic, oleophobic, and self-cleaning properties, which can avoid dust accumulation and blockage in the gaps between fins, extend the cleaning and maintenance cycle of air conditioning from the traditional 3 months to 12 months, and reduce operation and maintenance costs by more than 60%.

3. Wide range adaptation and compatibility, suitable for all operating conditions of air conditioning

The temperature resistance range of this coating covers -50 ℃ to 150 ℃, suitable for the working temperature range of air conditioning evaporators and condensers. Its adhesion to aluminum substrate reaches level 1, which can adapt to temperature fluctuations and vibrations during air conditioning operation, and will not peel off during sudden cooling and heating. The construction process is simple, and there is no need to modify the original heat exchanger structure. It can be put into use after 2 hours of surface drying and 24 hours of actual drying, making it suitable for mass production of new air conditioners and energy-saving renovation of existing air conditioners.

Data shows that bare aluminum tube air conditioners consume 15.9% more electricity per unit time than copper tubes, and their cooling time is extended by 25%; After coating, the energy consumption per unit time of aluminum tube air conditioning is only 1.2% higher than that of copper tube, and the cooling time and fan speed are basically close to the level of copper tube. The energy consumption per unit cooling capacity is only 0.01 kW · h/kW different. Based on the residential electricity price of 0.55 yuan/kWh, 120 days of summer cooling, and 8 hours of daily operation, the experimental group's air conditioning consumes 806.4 kW · h of electricity annually, saving 115.2 kW · h compared to bare aluminum tube air conditioning and saving 63.36 yuan in electricity costs annually.

Experimental data and engineering practice have proven that applying ZS-411 radiation heat dissipation coating (150 ℃) on air conditioning aluminum tube evaporators and condensers can enhance radiation heat transfer and improve corrosion resistance, making aluminum tube heat exchangers comparable to copper tube products in core performance indicators, while achieving significant energy-saving benefits and cost advantages.