Does the refrigerant heat exchange plate expansion tube type have thermal stress concentration under low temperature conditions?
Publish Time: 2025-06-04
As an important part of modern refrigeration technology, the refrigerant heat exchange plate expansion tube type system is widely used in many fields such as air conditioning, refrigeration and freezing due to its high energy conversion efficiency and compact design. However, when operating under low temperature conditions, due to the difference in thermal expansion coefficient of materials and the existence of temperature gradient, thermal stress concentration may occur inside the equipment.
Effect of low temperature environment on materials
When the refrigerant heat exchange plate expansion tube type device works under extremely low temperature conditions, such as industrial refrigeration or certain special applications, its main constituent materials (such as stainless steel, aluminum alloy, etc.) will experience a significant shrinkage effect. This shrinkage not only changes the size of the material itself, but also may cause the risk of loosening or even breaking at the connection. Especially for the expansion tube, the joint between it and the heat exchange plate is often the key area of stress concentration, because it usually needs to withstand large mechanical loads and the influence of temperature changes.
Mechanism of thermal stress generation
Thermal stress is mainly caused by uneven thermal expansion caused by temperature differences between different parts. In the refrigerant heat exchange plate expansion tube type structure, due to the change in the flow direction of the refrigerant in the fluid channel, the temperature distribution in the local area is uneven, thus forming a temperature gradient. This non-uniform temperature field will cause the metal material to expand or contract to varying degrees, thereby causing thermal stress. Especially in low-temperature environments, the material hardness increases and the ductility decreases, making it easier for thermal stress to cause crack expansion and even damage.
Countermeasures and improvement measures
In order to alleviate the problem of thermal stress concentration that may occur under low-temperature conditions, we can start from two aspects: design optimization and technical improvement. First, the selection of materials and their matching should be fully considered in the design stage, and materials with similar thermal expansion coefficients should be combined as much as possible to reduce stress concentration caused by excessive thermal expansion differences. Secondly, through reasonable structural design, such as using flexible connections or adding buffer layers, stress can be absorbed and dispersed to a certain extent to avoid excessive local stress.
In summary, although the refrigerant heat exchange plate expansion tube type does have the risk of thermal stress concentration under low-temperature conditions, this problem can be effectively alleviated through scientific and reasonable design optimization and technical improvements. Future research should focus more on the application of new materials and the development of intelligent monitoring systems to monitor equipment status in real time and promptly warn of potential failures to ensure safe and stable operation of the system.
