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CN-121789620-B - Noise elimination module suitable for low temperature operating mode

CN121789620BCN 121789620 BCN121789620 BCN 121789620BCN-121789620-B

Abstract

The invention belongs to the technical field of wind tunnel tests, and discloses a silencing module suitable for a low-temperature working condition. The silencing module comprises an outer frame, standard silencing sheet units and screws, wherein the plurality of standard silencing sheet units are sequentially inserted into grooves on the inner side of the outer frame from top to bottom, the standard silencing sheet units at the top and the bottom are connected with the outer frame through the screws to form an integral structure, the standard silencing sheet units adopt integral panels in the length direction, no countercurrent steps, protrusions, pits or grooves exist in the airflow direction, and the downstream steps are not more than 0.2mm. The noise elimination module adopts modularized, standardized and detachable design, can adapt to the change of the nitrogen exhaust temperature of large-scale low-temperature equipment within 110-323K, can reduce the exhaust noise of a low-temperature wind tunnel, control the noise pollution intensity of the wind tunnel to the environment, lead the exhaust noise to reach the environmental protection requirement, has simple structure and economic materials, is convenient for maintenance, inspection and repair, and has engineering application value.

Inventors

  • GE YUHANG
  • SI BIAO
  • GAO RONG
  • YANG XIAOFENG
  • LUO YINZHOU
  • YANG HENG
  • HONG XINGFU

Assignees

  • 中国空气动力研究与发展中心高速空气动力研究所

Dates

Publication Date
20260512
Application Date
20260304

Claims (8)

  1. 1. The silencing module is characterized by comprising an outer frame, standard silencing sheet units (6) and screws (5), wherein the plurality of standard silencing sheet units (6) are sequentially inserted into inner grooves of the outer frame from top to bottom, and the top and bottom standard silencing sheet units (6) are connected with the outer frame through the screws (5) to form an integral structure; The standard silencing sheet unit (6) adopts an integral panel in the length direction, no countercurrent step, protrusion, pit or groove exists between the standard silencing sheet unit (6) and the outer frame along the airflow direction, and the downstream step is not more than 0.2mm; The standard silencing sheet unit (6) is freely contracted in an inner side groove of the outer frame, so that the standard silencing sheet unit is suitable for the change of the nitrogen exhaust temperature of large-scale low-temperature equipment within the range of 110K-323K; The standard silencing sheet unit (6) is made of 304L austenitic stainless steel; the standard silencing sheet unit (6) comprises a framework, a honeycomb block (604) and a surface layer; The framework comprises 1 micro-perforated plate II (602) parallel to the air flow direction, and a plurality of partition plates (605) perpendicular to the micro-perforated plate II (602) and sequentially arranged along the air flow direction, wherein honeycomb blocks (604) are filled in the framework; The surface layer comprises a microperforated panel I (601) covering the right side of the framework, a microperforated panel III (603) covering the left side of the framework, a baffle (607) covering the top surface of the framework, and boss members (606) covering the front side and the rear side of the framework and respectively matched with the grooves of the sharp corner transition piece (2) and the arc transition piece (1).
  2. 2. The muffling module suitable for low-temperature working conditions according to claim 1, wherein the outer frame and the screws (5) are made of 304L austenitic stainless steel.
  3. 3. The silencing module suitable for the low-temperature working condition according to claim 1, wherein the outer frame comprises a sharp corner transition piece (2) and an arc transition piece (1) which are positioned at the front side and the rear side, the sharp corner transition piece (2) faces to the incoming flow, a top plate (4) and a bottom plate (3) which are positioned at the upper side and the lower side, and the front end and the rear end of the top plate (4) and the bottom plate (3) are fixedly connected with the sharp corner transition piece (2) and the arc transition piece (1) by bolts (5) respectively; The arc transition piece (1) comprises a semicircular section pipe body and arc rib plates (101) which are uniformly distributed along the height direction of the semicircular section pipe body, wherein the front end surface of the arc transition piece (1) is provided with grooves matched with the standard silencing sheet units (6); the sharp corner transition piece (2) comprises a triangular section pipe body and sharp corner rib plates (201) which are uniformly distributed along the height direction of the triangular section pipe body, and the rear end surface of the sharp corner transition piece (2) is provided with a groove matched with the standard silencing sheet unit (6); The thickness of the plates of the sharp corner rib plates (201) of the circular arc rib plates (101) is 1.5mm.
  4. 4. The noise elimination module suitable for the low-temperature working condition according to claim 3 is characterized in that the bottom plate (3) is a flat plate, the front end of the bottom plate (3) is a triangular plate matched with the sharp corner transition piece (2), a plurality of screw holes matched with the sharp corner transition piece (2) are formed in the triangular plate, the rear end of the bottom plate (3) is a semicircular plate matched with the circular arc transition piece (1), a plurality of screw holes matched with the circular arc transition piece (1) are formed in the semicircular plate, and a groove matched with the standard noise elimination sheet unit (6) is formed in the middle section of the bottom plate (3); The top plate (4) and the bottom plate (3) have the same structure and are arranged symmetrically up and down.
  5. 5. The muffler module for low temperature operation according to claim 4, wherein the micro perforated plate II (602) divides the standard muffler plate unit (6) into a left part and a right part, facing the incoming flow, the thickness of the left side is 120mm, and the thickness of the right side is 80mm.
  6. 6. The muffling module suitable for the low-temperature working condition according to claim 5, wherein the thickness of each of the microperforated panel I (601), the microperforated panel II (602) and the microperforated panel III (603) is 0.8mm, through holes which are uniformly distributed are formed in the surface of each of the microperforated panel I (601), the opening ratio of each of the microperforated panel II (602) and the microperforated panel III (603) is 2%, and the opening ratio of each of the microperforated panels II (602) and III (603) is 1%.
  7. 7. The muffling module suitable for low-temperature working conditions according to claim 5, wherein the honeycomb blocks (604) are fixedly connected with each other by adopting a vacuum brazing process, wherein the opposite edge distance of each honeycomb block (604) is 15mm, the wall thickness of each honeycomb block is 0.1mm, and each honeycomb block (604) is fixedly connected with an adjacent microperforated plate and each honeycomb block (604) is fixedly connected with a boss member (606).
  8. 8. The muffler module as defined in claim 5, wherein the thickness of the plates of the baffle plate (605), the boss member (606) and the baffle plate (607) is 1.5mm.

Description

Noise elimination module suitable for low temperature operating mode Technical Field The invention belongs to the technical field of wind tunnel tests, and particularly relates to a silencing module suitable for a low-temperature working condition. Background The large-scale low temperature equipment continuously discharges nitrogen in the test process, and the exhaust noise is required to meet three standards of industrial enterprise design sanitation standard (GBZ-2002), industrial enterprise factory environment noise emission standard (GB 12348-2008) and acoustic environment quality standard (GB 3096-2008), and a silencing module is required to be arranged in an exhaust silencer so as to reduce the exhaust noise, control the environmental noise pollution intensity and meet the environmental protection requirement. The nitrogen exhaust temperature of the large-scale low-temperature equipment ranges from 110K to 323K, the temperature of the exhausted nitrogen gas flow is extremely low when the muffler runs at low temperature, and the conventional sound absorption material can frost and even ice in a low-temperature environment, so that the sound absorption performance of the muffler is reduced. In addition, because of the small exhaust pressure loss required during normal pressure operation, sintered wire mesh cannot be adopted as a noise reduction measure. Therefore, no suitable noise reduction product exists in the current market, and the noise reduction function can be realized under the working conditions of wide temperature range alternation and low pressure loss, so that development of a noise elimination module suitable for the low temperature working condition is needed. Disclosure of Invention The invention aims to provide a silencing module suitable for a low-temperature working condition. The invention relates to a silencing module suitable for a low-temperature working condition, which comprises an outer frame, standard silencing sheet units and screws, wherein a plurality of standard silencing sheet units are sequentially inserted into an inner side groove of the outer frame from top to bottom, and the top and bottom standard silencing sheet units are connected with the outer frame through the screws to form an integral structure; The standard silencing sheet unit adopts an integral panel in the length direction, no countercurrent step, protrusion, pit or groove exists between the standard silencing sheet unit and the outer frame along the airflow direction, and the downstream step is not more than 0.2mm; The standard silencing sheet unit is freely contracted in the inner side groove of the outer frame, and is suitable for the change of the nitrogen exhaust temperature of large-scale low-temperature equipment within the range of 110K-323K. Further, the outer frame, the standard silencing sheet unit and the screws are all made of 304L austenitic stainless steel. Further, the outer frame comprises a sharp corner transition piece and an arc transition piece which are positioned at the front side and the rear side, and the sharp corner transition piece faces to the incoming flow; the device also comprises a top plate and a bottom plate which are positioned on the upper side and the lower side, wherein the front end and the rear end of the top plate and the bottom plate are respectively fixedly connected with the sharp corner transition piece and the arc transition piece by adopting screws; The arc transition piece comprises a semicircular section pipe body and arc rib plates uniformly distributed along the height direction of the semicircular section pipe body, wherein the front end surface of the arc transition piece is provided with a groove matched with a standard silencing sheet unit; The sharp corner transition piece comprises a triangular section pipe body and sharp corner rib plates uniformly distributed along the height direction of the triangular section pipe body, and the rear end surface of the sharp corner transition piece is provided with a groove matched with the standard silencing sheet unit; The thickness of the plates of the sharp corner rib plates of the arc rib plates is 1.5mm. The base plate is a flat plate, the front end of the base plate is a triangular plate matched with the sharp corner transition piece, a plurality of screw holes matched with the sharp corner transition piece are formed in the triangular plate, the rear end of the base plate is a semicircular plate matched with the circular arc transition piece, a plurality of screw holes matched with the circular arc transition piece are formed in the semicircular plate, and a groove matched with a standard silencing sheet unit is formed in the middle section of the base plate; The top plate and the bottom plate have the same structure and are arranged symmetrically up and down. Further, the standard silencing sheet unit comprises a framework, honeycomb blocks and a surface layer; The framework comprises 1 micro-perforate