【導(dǎo)讀】作復(fù)雜，對(duì)技術(shù)人員要求較高，而且不具有實(shí)時(shí)性。迫切需要各種方法簡(jiǎn)單，準(zhǔn)。本文介紹了一種氣體泄漏超聲檢測(cè)系統(tǒng),在分析小孔氣體。泄漏產(chǎn)生超聲波的原理的基礎(chǔ)上,闡述了該檢測(cè)系統(tǒng)的原理及設(shè)計(jì)方案。能對(duì)各種壓力容器的孔隙泄漏所產(chǎn)生的微弱超聲信號(hào)進(jìn)行精確檢測(cè)。檢測(cè)及泄漏量的估算。通過(guò)超聲波檢測(cè)，正確地判斷和定位產(chǎn)生泄漏位置，對(duì)于。提高企業(yè)的生產(chǎn)效率，節(jié)約能源，確保安全具有重大意義?？諝庵袀鞑ゾ哂泻軓?qiáng)的方向性。電路；數(shù)字電路由單片機(jī)和LCD、鍵盤(pán)等外圍設(shè)備組成。信號(hào)的強(qiáng)度與流速；另一路通過(guò)降頻轉(zhuǎn)化為可聽(tīng)聲，從而實(shí)現(xiàn)檢測(cè)的目的。

　　

【正文】 后，信號(hào)進(jìn)入帶通濾波器，輸出波形的中心頻率為 40K，帶寬為 38K 至 40K； （ 6） 該信號(hào)進(jìn)入精密檢波電路，精密檢波電路的作用是將正弦波轉(zhuǎn)變?yōu)殡妷簽? 伏 的直流信號(hào)； （ 7） 最后信號(hào) A/D 轉(zhuǎn)換電路進(jìn)行 AD 采樣。 （ 8） 第二線路的測(cè)試：由本振電路產(chǎn)生頻率為 37K 的多諧振蕩波； （ 9） 在端口 1輸入頻率為 3842K的正弦波并與 37K的多諧振蕩波進(jìn)行混頻，混頻后 進(jìn)入低通濾波器后，得到頻率 03K 的信號(hào)； （ 10） 最后信號(hào)進(jìn)入音頻功放電路，喇叭口處產(chǎn)生響聲，此完成整個(gè)調(diào)試過(guò)程。 6 結(jié)論 本文設(shè)計(jì)和制作了氣體泄漏超聲波檢測(cè)系統(tǒng)，該電路主要以性能穩(wěn)定、簡(jiǎn)單實(shí)用為目的，整體制作符合要求。 通過(guò)概述使大家充分了解了該檢測(cè)系統(tǒng)的原理與功能。從摘要和引言部分概要介紹了其可靠性和實(shí)用性。第一章介紹了氣體泄漏檢測(cè)方案的選擇和論證，從絕對(duì)壓力法、壓差法、超聲波檢測(cè)法相比較中，選出最佳方法；第二章介紹泄漏檢測(cè) 的設(shè)計(jì)原理，從對(duì)氣體泄漏產(chǎn)生一定頻率的聲波現(xiàn)象中發(fā)現(xiàn)了存在有超聲波，通過(guò)對(duì)超聲波的檢測(cè)來(lái)判斷泄漏的確切位置，并且從數(shù)學(xué)的角度分析了聲壓與泄漏量的關(guān)系；第三章詳細(xì)介紹超聲檢測(cè)電路設(shè)計(jì)原理與各單元電路的設(shè)計(jì)，從系統(tǒng)原理的角度得出系統(tǒng)分為模擬和數(shù)字兩部分；第四、五章介紹了軟件設(shè)計(jì)與電路調(diào)試過(guò)程。 通過(guò)本次電路的制作，我對(duì)氣體泄漏超聲檢測(cè)系統(tǒng)原理有了進(jìn)一步的了解，在氣體泄漏的分析中對(duì)超聲波檢測(cè)產(chǎn)生了濃厚的興趣，提高了科學(xué)的分析和運(yùn)用能力。 本電路雖然已完成實(shí)際制作，并且符合要求，但也存在許多需要完善的地方，由于本人 水平有限，因此對(duì)其中的原理和實(shí)際操作方法有待深入的學(xué)習(xí)研究和提高。文中有不足之處懇請(qǐng)各位老師加以指導(dǎo)，本學(xué)生衷心感謝。 謝 辭 本文是在導(dǎo)師晉良念老師悉心指導(dǎo)和鼓勵(lì)下完成的。論文的選題、具體工作和撰寫(xiě)過(guò)程都凝聚著導(dǎo)師的心血和汗水。晉良念老師淵博的知識(shí)，嚴(yán)謹(jǐn)?shù)闹螌W(xué)態(tài)度和一絲不茍的工作作風(fēng)給我留下了深深的印象，使我受益匪淺。在設(shè)計(jì)、制作到論文的完成過(guò)程中，晉良念老師盡量為我提供實(shí)踐基地和耐心指導(dǎo)，并且在生活上給予了極大的關(guān)心和幫助。在此向晉良念老師表示衷心的感謝和崇高的敬禮。 最后感謝桂林電子科技大學(xué)的培 養(yǎng)，感謝所有教過(guò)和沒(méi)教過(guò)我課的老師。衷心感謝在百忙中抽空參加論文評(píng)審的各位老師，感謝他們?yōu)楸疚母冻龅男燎趧趧?dòng)。另外還得感謝辛苦培養(yǎng)我的父母，感謝他們的培養(yǎng)。 參考文獻(xiàn) [1] 王化祥，張淑英 .傳感器原理及應(yīng)用 [M].天津：天津大學(xué)出版社， . [2]于亞非 .用超聲波傳感器檢測(cè)氣體泄漏 [J].儀器與未來(lái)， 1992(8). [3]李光海，王勇等 .基于聲發(fā)射技術(shù)的管道泄漏檢測(cè)系統(tǒng) [J].自動(dòng)化儀表， [4]李群芳 .單片微型計(jì)算機(jī)與接口技術(shù) [M].北京：電子工業(yè)出版社， 2020. [5]李進(jìn)，陳會(huì)倉(cāng)等 .氣體泄漏超聲波檢測(cè)裝置 [J]. 工業(yè)儀表與自動(dòng)化裝置， 1996， (5). [6]龔其春，葉騫 .新型氣體泄漏超聲檢測(cè)系統(tǒng)的研究與設(shè)計(jì) [J].電子技術(shù)應(yīng)用， 2020， 3 [7] 袁易全 ,黃建人 . 高靈敏超聲檢漏儀的研究 [M].東南大學(xué)學(xué)報(bào) ， 1989 [8] 李建藩 .氣壓傳動(dòng)系統(tǒng)動(dòng)力學(xué)廣州 [M].華南理工大學(xué)出版社 ， 1991 [9]ATMEL Microcontroller with 8K Bytes Flash AT89C52. [10]Donald Circuit Analysis and Design(Second edition). Published by the McGrawHill panies,2020. r, but fainter now and desperately the horn was blow ing. Fierce and shrill rose the yells of the Orcs, and suddenly the horncalls ceased. Aragorn raced down the last slope, but before he could reach the hill39。s foot, the sounds died away。 and as he turned to the left and ran towards them they retreated, until at last he could hear them no more. Drawing his bright sword and crying _Elendil! Elendil!_ he crashed through the trees. A mile, maybe, from Parth Galen in a little glade not far from the la ke he found Boromir. He was sitting with his back to a great tree, as if he was resting. But Aragorn saw that he was pierced with many blackfeathered arrows。 his sword was still in his hand, but it was broken near the hilt。 his horn cloven in two was at his side. Many Orcs lay slain, piled all about him and at his feet. Aragorn knelt beside him. Boromir opened his eyes and strove to speak. At last slow words came. 39。I tried to ta ke the Ring from Fr odo 39。 he said. 39。I am sorry. I have paid.39。 His glance strayed to his fallen enemies。 twenty at least lay there. 39。They have gone: the Halflings: the Orcs have taken them. I think they are not dead. Orcs bound them.39。 He paused and his eyes closed wearily. Afte r a moment he spoke again. 39。Farewell, Aragorn! Go to Minas Tirith and save my people! I have failed.39。 39。No!39。 said Aragorn, taking his hand and kissing his brow. 39。You have conquered. Few have gained such a victory. Be at peace! Minas Tirith shall not fall!39。 Boromir smiled. 39。Which way did they go? Was Frodo there?39。 said Aragorn. But Boromir did not speak again. 39。Alas!39。 said Aragorn. 39。Thus passes the heir of Dehor, L ord of the Tower of Guard! This is a bitter end. Now the Company is all in ruin. It is I that have failed. Vain was Gandalf39。s trust in me. What shall I do now? Boromir has laid it on me to go to Minas Tirith, and my heart desires it。 but where are the Ring and the Bearer? How shall I find them and save the Quest from disaster?39。 He knelt for a while, bent with weeping, still clasping Boromir39。s hand. So it was that Lego las and Gimli found him. They came from the western slopes of the hill, silently, creeping through the trees as if they were hunting. G imli had his axe in hand, and Legolas his long knife: all his arrows were spent. When they came into the glade they halted in amazement。 and then they stood a moment with heads bowed in grief, for it seemed to them plain what had happened. 39。Alas!39。 said Legolas, ing to Aragorn39。s side. 39。We have hunted and slain many Orcs in the woods, but we should have been of more use here. We came when we heard the hornbut too late, it seems. I fear you have taken deadly hurt.39。 39。Boromir is dead,39。 said Aragorn. 39。I am unscathed, for I was not here with him. He fell defending the hobbits, while I was awa y upon the hill.39。 39。The hobbits!39。 cried Gimli 39。Where are they then? Where is Frodo?39。 39。I do not know,39。 answered Aragorn wearily. 39。Before he died Boromir told me that the Orcs had bound them。 he did not think tha t they were dead. I sent him to follow Merry and Pippin。 but I d id not ask him if Frodo or Sam were with him: not until it was too late. All that I have done today has gone amiss. What is to be done now?39。 39。First we must tend the fallen,39。 said Legolas. 39。We cannot leave him lying like carrion among these foul Orcs.39。 39。But we must be swift,39。 said Gimli. 39。He would not wish us to linger. We must follow the Orcs, if there is hope that any of our Company are living prisoners.39。 39。But we do not know whether the Ringbearer is with them or not 39。 said Aragorn. 39。Are we to abandon him? Must we not seek him first? An evil choice is now before us!39。 39。Then let us do first what we must do,39。 said Legolas. 39。We have not the time or the tools to bury our rade fitly, or to raise a mound over him. A cairn we might build.39。 39。The labour would be hard and long: there are no stones that we could use nearer than the waterside,39。 said Gimli. 39。Then let us lay