Download or read book The Role of Oxygen in Gun Barrel Erosion and Cracking A Shock Tube Gun Investigation written by and published by . This book was released on 1980 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt: Experiments to determine the individual contributors to gun barrel erosion in an oxidizing atmosphere were conducted in the Shock Tube Gun (STG), a ballistic compressor, designed and developed by Calspan Corporation. This facility can compress mixtures of pure gases and can generate flow conditions and cycle times similar to those experienced in large caliber guns. Tests were conducted with a mixture of argon and nitrogen to define the threshold erosion for an inert baseline. Small concentration of oxygen were substituted for nitrogen in the mix to quantify the oxidation effect. Subsequently, tests were conducted with various gas mixtures containing carbon dioxide, which dissociates to produce oxygen when compressed to high temperatures. The basic oxidation effect was observed to be nearly linear increase in erosion with oxygen concentration. A corresponding shift in the erosion threshold to less severe convective heating conditions was observed in response to surface chemistry. A similar effect was observed for carbon dioxide mixture where erosion was correlated in terms of the equilibrium concentration of oxygen at peak pressure. Surface cracking was observed and found to be most severe near the erosion threshold where the oxide layer was thickest. A white layer was observed in tests with oxygen in the absence of carbon dioxide.
Download or read book The Role of Carburization in Gun Barrel Erosion and Cracking written by C. C. Morphy and published by . This book was released on 1981 with total page 91 pages. Available in PDF, EPUB and Kindle. Book excerpt: The subject program is part of a continuing effort to identify distinct mechanisms that contribute to gun barrel wear and erosion. The chemical effect of a carburizing atmosphere in a gun tube was the main topic for investigation in this program. Experiments were conducted in the Shock Tube Gun (STG), a ballistic compressor, designed and developed by Calspan Corporation. This facility can compress mixtures of pure gases to simulate propellant gas flow condtions and cycle time experienced in large caliber guns. Test were conducted with a mixture of argon and nitrogen to delineate the threshold of simple melting erosion which served as a chemical inert baseline. Progressive substitution of carbon monoxide for nitrogen in the mix quantified the carburizing effect as a function of CO concentration. Subsequent tests were conducted with a gas mixture containing carbon monoxide, argon and helium to measure the carburizing effect as a function of cycle time. The basic carburizing effect was observed to be a shift in the erosion threshold to less severe convective heating conditions in response to surface chemistry. The magnitude of the shift appeared to be directly proportional to heating cycle time.
Download or read book Gas Chemistry Effects on Gun Barrel Erosion A Shock Tube Gun Investigation written by and published by . This book was released on 1982 with total page 99 pages. Available in PDF, EPUB and Kindle. Book excerpt: The subject program is part of a continuing effort to identify distinct mechanisms that contribute to gun barrel wear and erosion. The thermochemical effects of altering the CO/CO2 ratio of a propellant gas in a gun tube was the main topic for investigation in this program. Experiments were conducted in the Shock Tube Gun (STG), a ballistic compressor, designed and developed by Calspan Corporation. This facility can compress mixtures of pure gases to simulate propellant gas flow conditions and cycle times experienced in large caliber guns. Tests were conducted with mixture ratios of carbon monoxide and carbon dioxide that characterize the normal range of CO/CO2 ratios found in propellant gas, i.e., 2.0 to 8.1. Progressive substitution of carbon monoxide for nitrogen in the mix quantified erosion as a function of increasing Co concentration or CO/CO2 ratio. Subsequent tests were conducted with gas mixtures containing double the amount of carbon monoxide and carbon dioxide but with the same effect CO/CO2 ratio, to measure erosion as a function of absolute reactant concentration for the two gas species. The basic chemical effect was observed to be a shift in the erosion threshold to less severe convective heating conditions in response to increasing the CO/CO2 ratio above a value of 5.6. The magnitude of the shift appeared to be directly proportional to the absolute concentrations of the two reactant gases. Variation of both CO/CO2 ratio and absolute amounts of the two gases resulted in distinct changes in specimen surface characteristics, both at near threshold and above threshold flow conditions.
Download or read book Technical Abstract Bulletin written by and published by . This book was released on 1980 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Shock Tube Gun Melting Erosion Study written by Franklin A. Vassallo and published by . This book was released on 1979 with total page 117 pages. Available in PDF, EPUB and Kindle. Book excerpt: Heat transfer, melting, and erosion tests were conducted using a unique Shock Tube Gun Facility available at Calspan. Materials of interest were subjected to intense heating using non-reactive gas mixtures. Pure melting of materials was obtained at heating conditions representing those of actual guns. A computer code was formulated, written, tested, and shown to adequately normalize the gross thermal data, thus permitting determination of expected bore temperatures and/or material loss for given heating conditions. It was found that, although the bore surface temperature of steels tested in the non-reactive gases of the Shock Tube Gun achieved temperatures of the same magnitude as those in large caliber guns where bore surface cracking is produced, no similar surface cracking of steels was observed. It is concluded that chemical activity of gun gases is partially responsible for crack initiation in gun tubes. (Author).
Download or read book Annual Department of Defense Bibliography of Logistics Studies and Related Documents written by United States. Defense Logistics Studies Information Exchange and published by . This book was released on 1982 with total page 1044 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Government Reports Announcements Index written by and published by . This book was released on 1980 with total page 1056 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Government Reports Annual Index written by and published by . This book was released on 1980 with total page 1422 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sections 1-2. Keyword Index.--Section 3. Personal author index.--Section 4. Corporate author index.-- Section 5. Contract/grant number index, NTIS order/report number index 1-E.--Section 6. NTIS order/report number index F-Z.
Download or read book Physicochemical Aspects of Gun Barrel Erosion and Its Control written by and published by . This book was released on 1975 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gun tube erosion can be defined as the bore surface damage and bore enlargement caused by firing, which can lead to loss in accuracy and the effectiveness of the weapon. It is one of the two major factors on the basis of which gun tubes are condemned; the other factor being fatigue life, Erosion is a complex phenomenon resulting from the interaction of propellant gases and the projectile with the surface of the bore. The bore surface is exposed for a short time to temperature approaching the melting point of steel, pressures as high as 50,000 psi, reactive atmosphere composed of CO, CO2, H2O, H2, N2, and numerous other identified and unidentified constituents. Superimposed on these conditions are the high velocity of gases and swaging action of the projectile rotating band. It is the objective of this presentation to review the physicochemical processes involved in erosion and indicate some critical areas which need further investigation. Also, various efforts to control erosion in barrels will be briefly discussed.
Download or read book The Role of Nitrogen in Gun Tube Wear and Erosion written by and published by . This book was released on 2006 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: The U.S. Army Research Laboratory has recently made discoveries in the area of interior ballistic propellant combustion product interactions with a gun-tube bore. These discoveries were based on two hypotheses. The first was that the products could and are dynamically nitriding the bore of the gun, thus creating a nitride coating which inhibits the dissociation of CO and subsequently reduces the amount of carbon uptake. The second was that the combustion products richer in nitrogen have a lower temperature upon expansion in our experimental fixture as well as in a gun barrel. This is due to Joule and/or Joule-Thomson cooling effects. Both of these hypotheses were proven and validated through numerical and experimental methods. Higher nitrogen containing combustion products have definitively been shown to have relatively lower erosivity with respect to those having lower nitrogen content. These results have revolutionized the gun propellant development community in that for the first time, there is guidance for erosivity control through propellant chemical constituent formulation.
Download or read book 11th International Symposium on Ballistics Propulsion dynamics launch dynamics flight dynamics written by and published by . This book was released on 1989 with total page 878 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Crimes Committed by Terrorist Groups written by Mark S. Hamm and published by DIANE Publishing. This book was released on 2011 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is a print on demand edition of a hard to find publication. Examines terrorists¿ involvement in a variety of crimes ranging from motor vehicle violations, immigration fraud, and mfg. illegal firearms to counterfeiting, armed bank robbery, and smuggling weapons of mass destruction. There are 3 parts: (1) Compares the criminality of internat. jihad groups with domestic right-wing groups. (2) Six case studies of crimes includes trial transcripts, official reports, previous scholarship, and interviews with law enforce. officials and former terrorists are used to explore skills that made crimes possible; or events and lack of skill that the prevented crimes. Includes brief bio. of the terrorists along with descriptions of their org., strategies, and plots. (3) Analysis of the themes in closing arguments of the transcripts in Part 2. Illus.
Download or read book Applied Mechanics Reviews written by and published by . This book was released on 1994 with total page 390 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book History of Shock Waves Explosions and Impact written by Peter O. K. Krehl and published by Springer Science & Business Media. This book was released on 2008-09-24 with total page 1298 pages. Available in PDF, EPUB and Kindle. Book excerpt: This unique and encyclopedic reference work describes the evolution of the physics of modern shock wave and detonation from the earlier and classical percussion. The history of this complex process is first reviewed in a general survey. Subsequently, the subject is treated in more detail and the book is richly illustrated in the form of a picture gallery. This book is ideal for everyone professionally interested in shock wave phenomena.
Download or read book Mathematical Modeling Of Melting And Freezing Processes written by V. Alexiades and published by CRC Press. This book was released on 1992-11-01 with total page 342 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presents mathematical models of melting and solidification processes that are the key to the effective performance of latent heat thermal energy storage systems, utilized in a wide range of heat transfer and industrial applications.
Download or read book The Big Sleep written by Raymond Chandler and published by DigiCat. This book was released on 2022-08-16 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt: DigiCat Publishing presents to you this special edition of "The Big Sleep" by Raymond Chandler. DigiCat Publishing considers every written word to be a legacy of humankind. Every DigiCat book has been carefully reproduced for republishing in a new modern format. The books are available in print, as well as ebooks. DigiCat hopes you will treat this work with the acknowledgment and passion it deserves as a classic of world literature.
Download or read book America s Munitions 1917 1918 written by United States War Dept and published by Franklin Classics. This book was released on 2018-10-12 with total page 828 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work has been selected by scholars as being culturally important and is part of the knowledge base of civilization as we know it. This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. To ensure a quality reading experience, this work has been proofread and republished using a format that seamlessly blends the original graphical elements with text in an easy-to-read typeface. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
