Thermal design method of bus LED in-car screens
Thermal design method of LED car display
Practical application shows that currently more hot inside the LED display,heating more electronic parts and components for: LED lamp, driver IC,switching power supply. Therefore, thermal design of LED display, betweenthe heat source and the external environment offers a low thermal resistancepathway and ensure smooth implementation of heat delivered.
A body temperature below 1800 ° c, significant thermal radiation wavelengthis between 0.38~100 μ m, and most of the energy in the infrared 0.76~20 μm range, in the visible band, proportion of radiant energy is very low.Therefore, the LED display can be coated with a variety of colors. LEDscreen outside of the Sun, coating into the light you want to avoid visible light absorption.
From the usage of LED display screen considered leasing screens, indoorfixed methods of natural cooling heat sink installation screen, outdoorforced air cooling heat sink for fixed installation screen.
Outdoor fixed LED display, across the entire screen during installation,consider thermal design. Subject to location restrictions, as the LEDdisplay power consumption reduction, more and more customers will be nudeoutdoors LED display, and has no other secondary cooling measures. LEDdisplay for large-screen, only natural cooling heat sink, cooling capacitythan the poor. Therefore, the bus led display cabinet heat dissipationdesign is especially important. From the bus led display box usingconsidering multiple angles such as reliability, maintenance costs, forcedconvection cooling with fan cooling, is better heat dissipation.
Heater electronic components and cooling heat exchange areas, heatingelectronic components and cooling temperature difference directly affectheat transfer. This involves entering the LED display box of air flowdesign, wind tunnel design. Ventilation duct design, as far as possible theuse of straight pipes that carry air, avoid sharp bend and bend the pipe.Ventilation pipe should avoid sudden expansion or a sharp contraction.Extended angle should not exceed 20o, shrinkage cone angle of not greater than 60 o. Air ducts should be sealed, all lapped should follow the flowdirection.
Bus led display when the Cabinet body design, there are several pointsneeding attention: the air intake should be set on the lower side of thebox, but not too low to prevent dirt and water into the enclosure ofinstallation on the floor. Vents should be set close to the upper side of the box. Direction under the air box above the loop, dedicated air intake orexhaust vents should be used. Cooling air from the heat flow in electronicparts should be made, at the same time preventing airflow short circuits.Sets required at the air intake and the air outlet filter, prevent debrisfrom entering the box. Design should help make natural convection of forcedconvection. During design, ensure that the air inlet and exhaust ports tostay away from. To avoid using the cooling air. Taking into account theexpansion of the volume of air is heated, air outlet size air inlet shall be1.5 times the size of times-twice. Heating larger electronic components such as switching power supply should be as close as possible to the inlet. Makesure radiator slot parallel to the wind direction, radiator alveolar cannotstop the wind path.
Fan is installed on the system, due to structural constraints, air inlet andair outlet are blocked, the performance curves vary. Based on practicalexperience, fan inlets and the best 40mm distance from the block, if there are space constraints, should also have at least 20mm.
