SU935674A2 - Injection-type steam cooler - Google Patents

Description

I

The invention relates to a power system, in particular, to devices for controlling the temperature of superheated steam - injection coolers.

According to the main auth. No. 36802 is known an injection cooler containing a water dispenser mounted inside a protective thin-walled jacket of a steam line made in the form of a centrifugal nozzle, the axis of the outlet nozzle of which coincides with the axis of the pipe in the direction of movement of the vapor stream fij.

The disadvantage of this desuperheater is the risk of a water film on its wall. This can cause high thermal stresses and the formation of cracks in the metal of the protective jacket. The operation of the desuperheater with a damaged protective jacket, in turn, can lead to the formation of fatigue cracks in the metal of the desuperheater body.

The purpose of the invention is to increase reliability.

To achieve this goal, the desuperheater additionally contains thin-walled cylinders of different diameters, coaxially mounted inside a protective jacket with annular gaps and offset smaller relative to larger, and larger relative to the protective jacket in the direction of steam movement.

The drawing shows schematically an injection desuperheater, a longitudinal section,

The housing 1 has a water inlet 2 with a centrifugal ({yr. 3) for spraying water. Thin-walled cylinders It are mounted on fixed fasteners 5 and sliding supports 6. Cylinders k have a different Diameter, are installed coaxially inside the jacket with annular gaps and less offset from more, and more relative to the protective shirt in the direction of movement of the steam.

The desuperheater pa6otaeT follows.

Water droplets from the centrifugal nozzle, interacting with the steam flow, are entrained by it, moving along certain trajectories. Larger droplets deviate from the flow axis by a larger amount, their trajectories are steeper. Small droplets move along gentle trajectories, with a small deviation from the flow axis. Due to the TOMV, that the cylinders 4 are shifted relative to each other in the direction of the vapor, only some part of the droplet spectrum can reach the inner surface of each. At the same time, large drops fall on the inner surface of a cylinder with a larger diameter, smaller ones - on the surface follow, tsego, smaller diameter, etc. At the same time, none of the cylinders reach the critical density of irrigation of its surface with water droplets, at which the wall temperatures decreases to saturation temperature, and droplets that reach the walls are poured into the film. The single droplets that have reached the cylinders either evaporate on their surface or, when shot against a wall, return to the flow. Thus, the largest drops are removed from the stream.

WHAT helps to reduce the length of the evaporator section of the desuperheater.

Due to the reduction in the reflux density of the surfaces of the cylinders with water droplets, the formation of a water film on the wall of the desuperheater body becomes impossible. Installing thin-walled cylinders hardly increases the hydraulic resistance of the desuperheater. In this case, a more uniform temperature field of the metal of the desuperheater body is provided, which increases the reliability of the device and contributes to a reduction in the start-up time of the power unit. All this increases the efficiency and reliability of the unit as a whole.

Claims (1)

1. USSR author's certificate No. 36 “802, cl. F 22 G 5/12, 1968. Jx T