Radiation absorbing metal pipe

Abstract

The invention relates to the field of solar energy usage and, particularly, to solar systems, which operate on the base of concentration of direct solar radiation. The invention proposes a radiation absorbing metal pipe intended for heating gaseous medium or gaseous-liquid mixture. The proposed radiation absorbing metal pipe is constructed from perforated plates. These plates are provided with inclined or two-stage upright rims. The plates are stacked and sealingly joined with formation of a tubular unit. Such tubular units with absorbing coatings of their external surfaces can be applied in following solar thermal systems: parabolic trough collectors; solar thermal collectors with usage of linear Fresnel reflectors; for a system with an array of tracking mirrors and a central receiver mounted on a tower or on the ground.

1 . A radiation absorbing metal pipe intended for heating gaseous medium or gaseous-liquid mixture; said radiation absorbing metal pipe is constructed from stacked metal flat plates with perforations and inclined rims; said inclined rims of said stacked metal flat plates are sealingly joined by welding or brazing; the ends of the tubular unit fabricated from said stacked metal flat plates are sealingly joined with fittings; the external surfaces of said tubular unit and said fittings are covered with a radiation absorbing coating. 
     
     
         2 . The radiation absorbing metal pipe intended for heating gaseous medium or gaseous-liquid mixture as claimed in  claim 1 , wherein the metal flat plates are provided with upright two-step rims. 
     
     
         3 . The radiation absorbing metal pipe intended for heating gaseous medium or gaseous-liquid mixture as claimed in  claim 1 , wherein the difference between the outer radii of both steps of the upright rim approximates that of said rim width. 
     
     
         4 . The radiation absorbing metal pipe intended for heating gaseous medium or gaseous-liquid mixture as claimed in  claim 1 , wherein the metal flat plates have the circular shape. 
     
     
         5 . The radiation absorbing metal pipe intended for heating gaseous medium or gaseous-liquid mixture as claimed in  claim 1 , wherein the metal flat plates have the oval shape. 
     
     
         6 . The radiation absorbing metal pipe intended for heating gaseous medium or gaseous-liquid mixture as claimed in  claim 1 , wherein the metal flat plates have the rectangular shape. 
     
     
         7 . The radiation absorbing metal pipe intended for heating gaseous medium or gaseous-liquid mixture as claimed in  claim 1 , wherein the perforations are shaped as openings with nipples. 
     
     
         8 . The radiation absorbing metal pipe intended for heating gaseous medium or gaseous-liquid mixture as claimed in  claim 1 , wherein the perforated metal plates are provided with differently oriented central openings of such shape, which allows angular shifting of said adjacent perforated metal plates in the process of their stacking. 
     
     
         9 . The radiation absorbing metal pipe intended for heating gaseous medium or gaseous-liquid mixture as claimed in  claim 1 , wherein the radiation absorbing coating has selective radiation absorbing features. 
     
     
         10 . The radiation absorbing metal pipe intended for heating gaseous medium or gaseous-liquid mixture as claimed in  claim 1 , wherein said radiation absorbing metal pipe comprises two sealingly joined units: the first one is a common metal pipe and the second one is constructed from the sealingly joined stacked flat metal plates provided with the perforations. 
     
     
         11 . The radiation absorbing metal pipe intended for heating gaseous medium or gaseous-liquid mixture as claimed in  claim 1 , wherein there are metal longitudinal rods, which are joined by brazing or welding with the outer surface of the tubular unit constructed from the stacked metal flat plates; said rods likewise are covered with the radiation absorbing coating. 
     
     
         12 . A solar radiation receiver for a solar thermal collector constructed in the form of a parabolic trough (PTC) or the solar thermal collector constructed with application of linear Fresnel reflectors (LFR); said solar radiation receiver comprises:
 a radiation absorbing metal pipe constructed as it is described in  claim 1 ;   metal bellows, which are joined with two fittings of said radiation absorbing metal pipe;   a glass envelope, which is joined at its ends with said two metal bellows by two glass-to-metal sealings; said glass envelope is provided with an evacuating nozzle for vacuum creation between said radiation absorbing metal pipe and said glass envelope.   
     
     
         13 . The solar radiation receiver for a solar thermal collector constructed in the form of a parabolic trough (PTC), or the solar thermal collector constructed with application of linear Fresnel reflectors (LFR) as claimed in  claim 12 , wherein the radiation absorbing metal pipe comprises some sealingly joined units: a common metal pipe; the tubular unit assembled from the sealingly joined stacked plates provided with the perforations; fittings, which are joined with the free ends of said common pipe and said tubular unit. 
     
     
         14 . A solar radiation receiver for a solar thermal station with an array of tracking reflectors, wherein said solar radiation receiver is mounted on a tower (STP); said solar radiation receiver is constructed as a radiation receiving chamber with at least one glazed aperture intended for entering concentrated solar radiation from said tracking reflectors into the internal space of said radiation receiving chamber, wherein the internal space of said radiation receiving chamber consists of one or more rows of parallel radiation absorbing metal pipes; each said radiation absorbing metal pipe is constructed as it is claimed in  claim 1 ; the free ends of the fittings of said radiation absorbing metal pipe are joined with metal bellows; there are lower and upper headers, which are situated in said radiation receiving chamber and they are in fluid communication through said metal bellows with said radiation absorbing metal pipes. 
     
     
         15 . The solar radiation receiver for a solar thermal station with an array of tracking reflectors, wherein said solar radiation receiver is mounted on a tower (STP); said solar radiation receiver is constructed in the form of a radiation receiving chamber as it is claimed in  claim 14 , wherein each radiation absorbing metal pipe comprises several sealingly joined units: a common metal pipe and a tubular unit assembled from the sealingly joined stacked flat metal plates provided with the perforations; fittings, which are joined with the free ends of said common pipe and said tubular unit. 
     
     
         16 . The solar radiation receiver for a solar thermal station with an array of tracking reflectors, wherein said solar radiation receiver is mounted on a tower (STP) as claimed in  claim 14 ; said solar radiation receiver is applied for carrying out thermo-chemical reactions in a gaseous medium flowing in it. 
     
     
         17 . The solar radiation receiver for a solar thermal power station with an array of tracking reflectors, wherein said solar radiation receiver is mounted on a tower (STP) as claimed in  claim 14 ; said solar radiation receiver is applied for heating the pressurized air. 
     
     
         18 . The solar radiation receiver for a solar thermal power station with an array of tracking reflectors as it is claimed in  claim 14 , wherein the solar radiation receiver is mounted on the ground.