Outdoor LED large screen heat dissipation is also very important

Don't take the heat dissipation of outdoor LED large screens seriously. With the advent of summer, everyone will inevitably be extremely hot. Similarly, LED large screens are also more likely to heat up. High temperatures will lead to a rapid increase in the failure probability of electronic components, thus Lead to a decline in the reliability of led electronic display. One not paying attention may cause a fire. In order to control the temperature of the electronic components inside the LED large screen so that it does not exceed the specified maximum allowable temperature under the working environment of the LED large screen, it is necessary to carry out heat dissipation design for the LED large screen. The heat dissipation design of the led large screen, how to achieve low cost and high quality is the content of this article. There are three basic ways of heat transfer: conduction, convection and radiation. Heat conduction: Gas heat conduction is the result of gas molecules colliding with each other when they move irregularly. Heat conduction in metal conductors is mainly accomplished by the movement of free electrons. Heat conduction in nonconductive solids is achieved through vibrations in the lattice structure. The heat conduction mechanism in the liquid mainly depends on the action of elastic waves. Convection: refers to the heat transfer process caused by the relative displacement between the various parts of the fluid. Convection occurs only in fluids and is necessarily accompanied by conduction. The heat exchange process that occurs when a fluid flows over the surface of an object is called convective heat transfer. The convection caused by the different density of the hot and cold parts of the fluid is called natural convection. If the movement of the fluid is caused by an external force (fan, etc.), it is called forced convection. Radiation: The process by which an object transmits energy in the form of electromagnetic waves is called thermal radiation. Radiant energy transfers energy in a vacuum, and there is a conversion of energy forms, that is, thermal energy is converted into radiant energy and radiant energy is converted into thermal energy. When choosing a heat dissipation method, the following factors should be considered: heat flux density, volume power density, total power consumption, surface area, volume, and working environment conditions (temperature, humidity, air pressure, dust, etc.) of the LED large screen. According to the heat transfer mechanism, there are natural cooling, forced air cooling, direct liquid cooling; evaporative cooling; thermoelectric cooling; heat pipe heat transfer and other heat dissipation methods. Heat dissipation design method of large led screen The heat exchange area between the heating electronic components and the cold air, and the temperature difference between the heating electronic components and the cold air directly affect the heat dissipation effect. This involves the design of the air volume entering the LED display box and the design of the air duct. When designing ventilation ducts, try to use straight ducts to convey air, and avoid sharp bends and curved ducts. Ventilation ducts should avoid sudden expansion or contraction. The expanded opening angle should not exceed 20o, and the contracted cone angle should not exceed 60o. Ventilation ducts should be as tight as possible and all overlaps should be in the direction of flow. When designing the LED large screen cabinet, there are a few points to pay attention to: (1) The air intake hole should be set on the lower side of the cabinet, but not too low, so as to prevent dirt and water from entering the cabinet installed on the ground. (2) The exhaust hole should be set near the upper side of the box. (3) The air should circulate from the bottom of the box to the top, and special air intake or exhaust holes should be used. (4) The cooling air should flow through the heating electronic components, and the short circuit of the air flow should be prevented at the same time. (5) Filter screens should be installed at the air inlet and air outlet to prevent debris from entering the box. (6) The design shall make natural convection helpful to forced convection. (7) When designing, it is necessary to ensure that the air inlet and the exhaust port are far away. Avoid reusing cooling air. (8) Ensure that the direction of the radiator slots is parallel to the wind direction, and the radiator slots cannot block the air path. (9) When the fan is installed in the system, due to structural limitations, the air inlet and outlet are often blocked by various obstacles, and its performance curve will change. According to practical experience, the air inlet and outlet of the fan should have a distance of 40mm from the barrier, and if there is a space limit, it should be at least 20mm. .