Abstract: The present disclosure discloses a classified heat dissipation system including an accommodating area, a group to be heat dissipated, an air cooling device, and a liquid cooling device. A top end of the accommodating area is provided with a thermal sandwich channel. The group to be heat dissipated is installed in the accommodating area, the group to be heat dissipated includes at least two device groups, a thermal channel is surrounded between the at least two device groups, and the thermal channel is communicated with the thermal sandwich channel, where each of the at least two device groups has rest of heating sources and a plurality of primary heating sources. The air cooling device conveys cold air into the accommodating area, and the cold air enters the thermal sandwich channel through the device group and the thermal channel. The liquid cooling device is in contact with the primary heating sources.

Abstract: The present disclosure discloses a combined air-cooling and liquid-cooling refrigeration system and a data center, where the combined air-cooling and liquid-cooling refrigeration system includes a closed area, a combined device group, and a circulating liquid-cooling system. The combined device group and the circulating liquid-cooling system are installed in the closed area. The combined device group includes a first device group and a second device group, and a closed thermal channel is formed between the first device group and the second device group. The first device group and the second device group each include a plurality of air cooling devices and a plurality of heating devices. The circulating liquid-cooling system is connected to primary heating sources of the plurality of heating devices, and the plurality of air cooling devices refrigerate hot air discharged from the closed thermal channel.