<b>Ultrasonic　Attenuation　in　Ethylene　and　Air　Gas　Mixtures </b>

DOI Web Site 1 Citations

Bibliographic Information

Other Title
  • <b>エチレンー空気混合ガスの超音波減衰特性</b>
  • エチレンー空気混合ガスの超音波減衰特性
  • エチレン クウキ コンゴウ ガス ノ チョウオンパ ゲンスイ トクセイ

Search this article

Abstract

<p><tt>This　paper　describes　the　possibility　of　a　C2H4 concentration　monitor　using　with　the　ultrasonic　attenuations　in　mixtures of　C2H4 and　air. Measurements　of　the　attenuation　per　unit　distance　of 215 kHz　ultrasonic　pulses　were　carried　out　by　varying the　length　of　the　test　cell　</tt><tt>of 34 mm　in　diameter　from 30 mm　to 300 mm. The　attenuations　of　C2H4 and　air　mixtures　are extremely　large　compared　with　air　and　C2H4．From　these　fundamental　results，the　practical　gas　detection　cells　and　the detection </tt><tt>method　in　order　to　monitor　the　gas　concentration　were　developed．The　two 215 kHz　ultrasonic　transducers　were installed　on　the　both　sides　of　the　gas　detection　cell　of 4 mm　in　diameter　and 70 mm　or 40 mm　</tt><tt>long．The　ultrasonic　pulses were　sent　intermittently　from　the　trallsducer　and　were　propagated　through　the　cell.　The　sound　pressure　of　the　ultmsonic waves　were　detected　by　another　transducer　on　the　other　side．　The　peek　detected　value　of　the　souod　pressure　in　the　first receiving　waves　ls　decayed　sharply　introducing　C2H4 </tt><tt>and　air　mixtures　in　to　the　cell.　The　relationship　between　the　peek detected　value，P1 and　C2H4 concentration，C（％）, was　measured.</tt></p><p><tt> The　summary　of　the　measurements　is　as　follows:</tt></p><p><tt> a）The peek detected value P1 of the soud presure extremely decreases with increasing C2H4 concentration in a range of　C=0～20％（Fig．5 a，b）．However P1 is　almost　constant for　a　range　of　C＞20％．The former range　is suitable for a　C2H4 monitor．</tt></p><p><tt>b）　The　gas　temperature　dependence　on　P1　was　measured　in　a　range 1O～40℃ while　P1 decreases　with　increasing　temperature（Fig.8），the　attenuation　per　unit　distance　is　almost　independent　of　the　temperature（Fig.9）.</tt></p><p>c）　By　absorbing　water　vapor　into　the　gas，P1 becomes　smaller　than　the　dry　one（Fig．5a，b）．</p><p><tt>d）　The　C2H6 and　C2H4 gas　mixtures　were　also　investigated，The　</tt>P1<tt>　relatively　decreases　with　increasing　C2H6 concentra</tt><tt>tion　in　a　range　O～30％. The　C2H6 monitor　for　CC2H6 and　C2H4 gasmixtures　also　has　a　possibility（Fig.7〉.</tt></p>

Journal

Citations (1)*help

See more

Keywords

Details 詳細情報について

Report a problem

Back to top