Thermo nuclear time12/28/2022 ![]() Due to the tremendous compression of the atmosphere by the blast wave, the air in front of the fireball is heated to incandescence. ![]() At this point, the blast wave front begins to catch up with the surface of the fireball and then moves ahead of it, a process called hydrodynamic separation. As the fireball expands and its energy is deposited in an ever-increasing volume its temperature decreases and the transfer of energy by thermal radiation becomes less rapid. In addition to the high temperature of the nuclear fireball, the blackbody radiation is emitted in a characteristic two-peaked pulse with the first peak being due to the radiating surface of the outrunning shock. For detonations below 100,000 feet, 35 percent to 45 percent of the nuclear yield is effectively radiated as thermal energy. Both of these temperatures are well above that reached in conventional chemical explosions, about 5,000° K. For detonations occurring below 30,000 m (100,000 ft) these X-rays are quickly absorbed in the atmosphere, and the energy is reradiated at blackbody temperatures below 10,000° K. The fireball from a nuclear explosion reaches blackbody temperatures greater than 10 7 K, so that the energy at which most photons are emitted corresponds to the x-ray region of the electromagnetic spectrum. Absorption of thermal radiation will also cause the ignition of combustible materials and may lead to fires which then spread rapidly among the debris left by the blast. Such thermal injuries may occur even at distances where blast and initial nuclear radiation effects are minimal. ![]() The chief hazard of thermal radiation is the production of burns and eye injuries in exposed personnel. This thermal radiation travels outward from the fireball at the speed of light, 300,000 km/sec. Large amounts of electromagnetic radiation in the visible, infrared, and ultraviolet regions of the electromagnetic spectrum are emitted from the surface of the fireball within the first minute or less after detonation. ![]()
0 Comments
Leave a Reply.AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |