Direct-current arc cathode head with micro-rib structure in inner hole

Abstract

The invention relates to a direct-current arc cathode head with a micro-rib structure in an inner hole and belongs to the field of pulverized coal furnace direct-current arc plasma igniters. The cathode head comprises a main body, a contact part and a connecting part. The connecting part is arranged at a rear end of the main body; the contact part is arranged at a front end of the main body, and an area of a connection surface with the main body is larger than that of an opposite bottom surface; inner holes are arranged in the main body, the contact part and the connecting part; and a thermionic emission alloy material is arranged, the micro-rib structure is arranged on a side wall of each inner hole, and the micro-rib structure is also arranged at a front end of the contact part. By processing the micro-rib structure in the inner hole of the cathode head, a heat exchange area between the cathode head and cooling water is remarkably increased, and a heat transfer capacity is enhanced so that the cathode head is cooled more efficiently, heating erosion of the cathode head is weakened, and a service life of the cathode head is prolonged.

Description

technical field [0001] The invention belongs to the field of DC arc plasma igniters for pulverized coal furnaces, and relates to a DC arc cathode head with a micro-rib structure in the inner hole Background technique [0002] DC arc plasma ignition technology can realize oil-free coal-fired boilers, and has significant advantages such as high efficiency, energy saving, and no pollution. However, the cathode head of the DC arc plasma igniter of the pulverized coal furnace is severely eroded by heat due to the strong effect of the surrounding hot plasma spot (5000-10000K), and its life is usually only about 200h, which seriously affects the performance of the igniter; the traditional cathode The heat transfer surface of the inner hole is in the shape of a cylindrical light pipe, and its heat transfer area and heat transfer capacity are limited. When the DC arc power is increased by a large margin, the thermal erosion of the cathode is significantly enhanced, and the life is sh...

AI Technical Summary

Problems solved by technology

However, the cathode head of the DC arc plasma igniter of the pulverized coal furnace is severely eroded by heat due to the strong effect of the surrounding hot plasma spot (5000-10000K), and its life is usually only about 200h, which seriously affects the performance of the igniter; the traditional cathode The heat transfer surface of the inner hole is in the shape of a cylindrical light tube, and its heat transfer area and heat transfer capacity are limited. When the DC arc power is increased by a large margin, the thermal erosion of the cathode is significantly enhanced, and the life is shortened sharply.

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