【正文】 1. 本文通過對羅茨泵主要零件尺寸的計算，確定了羅茨泵的重要參數(shù)，為該泵的投產奠定了理論基礎。同時，本文中的對該泵的結構設計部分可以作為產品實際生產時的參考。2. 本文使用ANSYS軟件對該泵工作過程中的轉子進行了擬實分析，得出了本泵內轉子在不同溫度下的變形量，從而確定出防止轉子卡死的邊界條件，解決了關于該泵設計時的一項難點。論文的工作雖然已經完成，但是仍有一些問題有待今后進一步研究：1. 組成該泵的零部件相對較多，這使得裝配成為一個很繁重的任務。因此，無論是對泵的結構或是裝配方法都有待進一步的研究。2. 本文中僅使用ANSYS軟件對轉子塊進行了分析，實際上泵腔受熱膨脹的變形量也是一個對泵性能影響較大的因素，有待進一步對其分析研究。3. 本文中提出的防止轉子卡死的解決辦法尚不夠完善，增大沖入量的具體細節(jié)還需要進一步分析計算。結論本次畢業(yè)設計以渦輪分子泵為設計目標，至此設計工作已經全部完成。首先通過理論計算確定了主要設計參數(shù)，并在此基礎上進行了結構設計。本設計的專題部分為組合葉列優(yōu)化設計。在設計中對重要的零件進行了強度和疲勞的校核，同時進行了受力分析。結果顯示，本次設計的結構安全可行，重要的零件安全可靠，所以設計是成功的。在長期的畫圖過程中，熟練的掌握了畫圖的基本功。結合以上，通過十六周的努力，我很好的完成了本次畢業(yè)設計。參考文獻1. 、特征及其應用[J]，真空，2000(3)：1－92. [J]，四川真空，1991（1）：24－263. Duval, P. .Using roots pumps in microelectronic production facilities (L. P. CVD, PLASMAETCHING, REACTIVE ION ETCHING)[J], Annual Proceedings Reliability Physics (Symposium),1980,2:34374. Kanke Yukio,Tanaka Tomonari,Aikawa Junichi,Yuyama of the dry roots pump `DRYMAC39。 in LPCVD silicon nitride process[J], Applied Surface Science, 2001,1691705. 楊乃恒。渦輪分子泵倒錐式潤滑系統(tǒng)的設計方法?！墩婵铡?No．2，1984。6. ，真空，1999（2）：1~87. [M]，北京：冶金工業(yè)出版社，2001，59－848. ，沈陽：東北大學出版社，2000，4849；102135 9. [M]，北京：國防工業(yè)出版社，1991，51510. [J]，機械工程師，2001（1）：53－54，巴德純，楊乃恒，渦輪分子泵組合葉列幾何參數(shù)優(yōu)化設計方法的研究，《真空》,1999,[M]，北京：高等教育出版社，1992致謝在本次設計中我得到了巴德純教授的細心指導，在此，謹向巴老師致以衷心的感謝。本文是在劉坤老師的悉心指導下完成的。劉老師對學生認真負責的態(tài)度，嚴謹?shù)目蒲凶黠L、淵博的知識，使我從中受益非淺。在課題的研究過程中同時得到了肖玉、陳瑤兩位師姐的大力幫助和悉心點撥，以及實驗室其他師兄、師姐得幫助，使我能夠及時的完成設計任務。在此，對他們表示誠摯的感謝。最后，再一次向所有給予我無微不至關懷與幫助的人表示我最崇高的謝意。附錄英文原文Role of molecular diffusion in the theory of gas flowthrough crimpedcapillary leaksH. T. Bach,a) B. A. Meyer, and D. G. TuggleEngineering Science and Application Division, Tritium Science and Engineering Group,MS C927 Los Alamos National Laboratory, Los Alamos, New Mexico 87545~Received 17 December 2002。 accepted 3 March 2003。 published 28 April 2003!Gas flow through crimpedcapillary leaks was studied with the use of a mass spectrometric crimpedcapillary leak was used as a singlestage pressurereduction device between a gas inlet manifold and an ultrahighvacuum mass spectrometer. The steady state flows of binary gas mixtures(H2–4He and H2–D2) through the crimpedcapillary leak into the mass spectrometer vacuum chamber (,1029 Torr! were characterized over a pressure range from 5 to 5000 Torr. At pressures 5 and .1500 Torr, the gas flow is close to Knudsen diffusion ~molecular flow! and viscous flow,respectively. The transition from the Knudsen diffusion to viscous flow takes place over 2 decades of pressure and is at a lower pressure range than can be explained by the bined Knudsendiffusion and viscous flow theories. This article considers the contribution of molecular diffusion~ordinary diffusion! to the theory of gas flow through crimpedcapillary leak and presents a mathematical model for a multiponent gas mixture. This model successfully predicts gas flow over a wide range of pressures especially in the transition flow regime for binary gas mixtures.169。 2003 American Vacuum Society. @DOI: I. INTRODUCTIONAnalysis of gas mixtures using mass spectrometry has broad applications. Different techniques for introducing gas mixtures from an inlet system into a mass spectrometer undercontinuous and discontinuous conditions have been Under either condition, sample gas pressure is reduced in multiple steps to avoid mass fractionation. In adiscontinuous condition, a gas mixture is placed in a sample volume at a pressure of ,1 Torr. The gas mixture is introduced to the mass spectrometer through a molecular leak and is pumped out of the mass spectrometer with a molecular pump. The Knudsen diffusion ~molecular flow! of gas mixtures into the mass spectrometer is favorable because there isno mass fractionation. The partial pressure in the mass spectrometer ionization region of any gas ponent of the gas mixture is the same as that in the inlet system. For applicationsrequiring continuous analysis of a highpressure gas stream, different techniques for introducing the gas mixture are employed. The most mon one, a twostage pressurereduction device, is used to reduce the gas mixture pressure in two steps to avoid mass fractionation. In the first step, the high pressure is reduced to about 1–10 Torr, and the flow is purely viscous. In the second step, the pressure is reduced from 1 to 10 Torr to the proper operating pressure of the mass spectrometer (,1026 Torr!, and the flow is purely technique employs a single stage pressurereduction device. Sodal and Hanna have discussed the use of a pulse valve for continuous sampling from a wide range ofsample gas For our application, in which we are analyzing a rapid change in position of a highpressure gas stream, we are investigating the use of a crimpedcapillary leak for introducing gas mixtures into the mass spectrometer. The crimpedcapillary leak provides fast response time and only removes a small quantity of gas from the gas source where its total quantity is accurately quantified. However, the crimpedcapillary leak causes mass fractionation. The possibility of gas analysis errors due to mass fractionation is investigatedboth experimentally and theoretically.This article describes an experimental method using a mass spectrometric system to study gas flow through crimpedcapillary leak in different flow regimes. The article presents a mathematical model for the flow of a multiponent gas mixture and two limiting cases of pure gas and binary gas mixture. We pare the theoretical results with experimental data for binary gas mixtures. The proposed model successfully predicts the gas flow over a wide range of pressures especially in the transition flow regime. From these results, we can draw some general conclusions concerning the design and performance of the crimpedcapillary leak. The crimpedcapillary leak is mercially available. The cm length of stainlesssteel capillary tubing ~ cm inner diameter, cm outer diameter