Detonative cleaning apparatus

Abstract

An apparatus is provided for cleaning a surface within a vessel. A vessel wall separates a vessel exterior from a vessel interior and has a wall aperture. The apparatus comprises an elongate conduit having an upstream first end and a downstream second end. The conduit is positioned to direct a shock wave from the second end into the vessel interior. A source of fuel and oxidizer is coupled to the conduit to deliver the fuel and oxidizer to the conduit. An initiator is positioned to initiate a combustion of the fuel and oxidizer. The conduit comprises a first portion and a second portion downstream of the first portion. The second portion is extensible and contractible relative to the first portion to selectively position the second end at a desired location within the vessel. The conduit downstream end comprises a centerbody positioned to direct the shock wave essentially axisymmetrically.

1 . An apparatus for cleaning a surface within a vessel having a vessel wall separating a vessel exterior from a vessel interior and having a wall aperture, the apparatus comprising:
 an elongate conduit having an upstream first end and a downstream second end and positioned to direct a shock wave from the second end into the vessel interior; and   a source of fuel and oxidizer coupled to the conduit to deliver the fuel and oxidizer to the conduit; and   an initiator positioned to initiate a combustion of the fuel and oxidizer,   
     wherein:
 the conduit comprises a first portion and a second portion downstream of the first portion and extensible and contractible relative to the first portion to selectively position the second end at a desired location within the vessel; and 
 the conduit downstream end comprises a centerbody positioned to direct the shock wave essentially axisymmetrically 
 
   
   
       2 . The apparatus of  claim 1  further comprising:
 an actuator coupled to the conduit second portion to extend and contract the second portion relative to the first portion.   
   
   
       3 . The apparatus of  claim 2  wherein:
 neither the actuator, nor any other actuator, is configured to rotate the second portion relative to the first portion about a longitudinal axis.   
   
   
       4 . The apparatus of  claim 1  wherein:
 the centerbody defines an only outlet.   
   
   
       5 . The apparatus of  claim 1  wherein:
 the centerbody is essentially axisymmetric and held by a plurality of struts.   
   
   
       6 . The apparatus of  claim 1  wherein:
 the centerbody has an upstream surface concave in central longitudinal section.   
   
   
       7 . An apparatus for cleaning a surface within a vessel having a vessel wall separating a vessel exterior from a vessel interior and having a wall aperture, the apparatus comprising:
 an elongate conduit having an upstream first end and a downstream second end and positioned to direct a shock wave from the second end into the vessel interior; and   a source of fuel and oxidizer coupled to the conduit to deliver the fuel and oxidizer to the conduit; and   an initiator positioned to initiate a combustion of the fuel and oxidizer,   
     wherein:
 the conduit comprises a first portion and a second portion downstream of the first portion and extensible and contractible relative to the first portion to selectively position the second end at a desired location within the vessel; and 
 the conduit downstream end comprises a centerbody positioned to direct the shock wave from an opening of essentially 360°. 
 
   
   
       8 . The apparatus of  claim 7  further comprising:
 an actuator coupled to the conduit second portion to extend and contract the second portion relative to the first portion.   
   
   
       9 . An apparatus for cleaning a surface within a vessel having a vessel wall separating a vessel exterior from a vessel interior and having a wall aperture, the apparatus comprising:
 an elongate conduit having an upstream first end and a downstream second end and positioned to direct a shock wave from the second end into the vessel interior; and   a source of fuel and oxidizer coupled to the conduit to deliver the fuel and oxidizer to the conduit; and   an initiator positioned to initiate a combustion of the fuel and oxidizer,   
     wherein:
 the conduit comprises a first portion and a second portion downstream of the first portion and extensible and contractible relative to the first portion to selectively position the second end at a desired location within the vessel; and 
 the conduit downstream end comprises a pair of axially aligned outlet openings. 
 
   
   
       10 . The apparatus of  claim 9  wherein:
 the outlet openings are diametrically opposed.   
   
   
       11 . A method for cleaning a surface within a vessel having a vessel wall separating a vessel exterior from a vessel interior and having a wall aperture, the method comprising:
 introducing of fuel and oxidizer to an elongate conduit having an upstream first end and a downstream second end, the second end within the vessel;   initiating a combustion of the fuel and oxidizer; and   discharging a shock wave from the second end into the vessel interior;   
     wherein:
 the discharging is from an opening essentially circumscribing an axis of the conduit between a centerbody and a portion of the conduit upstream of the centerbody. 
 
   
   
       12 . The method of  claim 11  wherein:
 the conduit comprises a first portion and a second portion downstream of the first portion, the centerbody being along the second portion; and   the method includes at least one of extending and contracting the second portion relative to the first portion to selectively position the second end at a desired location within the vessel between a plurality of cycles of the discharging.   
   
   
       13 . The method of  claim 12  wherein:
 an overall cleaning cycle is performed including a plurality of movements in the absence of a rotation of the second portion.