{"4c6736eaad1cdfd3d26e2869a60c8e25hermann":{"DOI":"10.1016/j.actaastro.2016.09.031","ISBN":"","ISSN":"0094-5765","URL":"","abstract":"Microgravity experiments are essential for research in space science,\n   biology, fluid mechanics, combustion, and material sciences. One way to\n   conduct microgravity experiments on Earth is by using drop tower\n   facilities. These facilities combine a high quality of microgravity,\n   adequate payload masses and have the advantage of virtually unlimited\n   repeatability under same experimental conditions, at a low cost.\n   In a collaboration between the Institute of Space Systems (IRS) at the\n   University of Stuttgart and Baylor University (BU) in Waco, Texas, a new\n   drop tower is currently under development at the Center for\n   Astrophysics, Space Physics and Engineering Research (CASPER). The\n   design parameters of the drop tower ask for at least 1.5 sin free fall\n   duration while providing a quality of at least 10(-5) g. Previously,\n   this quality has only been achieved in vacuum drop tower facilities\n   where the capsule experiences virtually zero aerodynamic drag during its\n   free fall. Since this design comes at high costs, a different drop tower\n   design concept, which does not require an evacuated drop shaft, was\n   chosen. It features a dual-capsule system in which the experiment\n   capsule is shielded from aerodynamic forces by surrounding it with a\n   drag shield during the drop. As no other dual-capsule drop tower has\n   been able to achieve a quality as good as or better than 10-5 g previous\n   work optimized the design with an aerodynamic perspective by using\n   computational fluid dynamics (CFD) simulations to determine the ideal\n   shape and size of the outer capsule and to specify the aerodynamically\n   crucial dimensions for the overall system. Experiments later\n   demonstrated that the required quality of microgravity can be met with\n   the proposed design.\n   The main focus of this paper is the mechanical realization of the\n   capsule as well as the development and layout of the surrounding\n   components, such as the release mechanism, the deceleration device and\n   the drop shaft. Because the drop tower facility is a complex system with\n   many interdependencies between all of the components, several\n   engineering challenges had to be addressed. For example, initial\n   disturbances that are caused by the release mechanism are a common issue\n   that arises at drop tower facilities. These vibrations may decrease the\n   quality of microgravity during the initial segment of free fall. Because\n   this would reduce the free fall time experiencing high quality\n   microgravity, a mechanism has been developed to provide a soft release.\n   Challenges and proposed solutions for all components are highlighted in\n   this paper.","annote":"","author":[{"family":"Belser","given":"Valentin"},{"family":"Breuninger","given":"Jakob"},{"family":"Reilly","given":"Matthew"},{"family":"Laufer","given":"Rene"},{"family":"Dropmann","given":"Michael"},{"family":"Herdrich","given":"Georg"},{"family":"Hyde","given":"Truell"},{"family":"Roeser","given":"Hans-Peter"},{"family":"Fasoulas","given":"Stefanos"}],"citation-label":"ISI:000389087900038","collection-editor":[],"collection-title":"","container-author":[],"container-title":"ACTA ASTRONAUTICA","documents":[],"edition":"","editor":[],"event-date":{"date-parts":[["{2016}","DEC"]],"literal":"{2016}"},"event-place":"THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND","id":"4c6736eaad1cdfd3d26e2869a60c8e25hermann","interhash":"68be0ef6c5ff6d2cf0fc2d567af19efc","intrahash":"4c6736eaad1cdfd3d26e2869a60c8e25","issue":"","issued":{"date-parts":[["{2016}","DEC"]],"literal":"{2016}"},"keyword":"Aerodynamic Deceleration tower; mechanism; optimization} {Microgravity; device; Drop Release","misc":{"author-email":"{valentinbelser@web.de}","issn":"{0094-5765}","funding-acknowledgement":"{Cooper Foundation in Waco, Texas}","research-areas":"{Engineering}","eissn":"{1879-2030}","number-of-cited-references":"{8}","web-of-science-categories":"{Engineering, Aerospace}","affiliation":"{Belser, V (Reprint Author), Univ Stuttgart, Stuttgart, Germany.\n   Belser, Valentin; Breuninger, Jakob; Laufer, Rene; Dropmann, Michael; Herdrich, Georg; Roeser, Hans-Peter; Fasoulas, Stefanos, Univ Stuttgart, Inst Space Syst IRS, Stuttgart, Germany.\n   Belser, Valentin; Breuninger, Jakob; Reilly, Matthew; Laufer, Rene; Dropmann, Michael; Herdrich, Georg; Hyde, Truell, Baylor Univ, CASPER, Waco, TX 76798 USA.}","funding-text":"{The author wants to acknowledge the Cooper Foundation in Waco, Texas,\n   mainly funding the BU drop tower and Dr. Rene Laufer, Dr. Truell Hyde\n   and Dr. Georg Herdrich for their great project supervision.}","language":"{English}","times-cited":"{0}","doi":"{10.1016/j.actaastro.2016.09.031}"},"note":"","number":"","number-of-pages":"9","page":"335-344","page-first":"335","publisher":"PERGAMON-ELSEVIER SCIENCE LTD","publisher-place":"THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND","status":"","title":"Aerodynamic and engineering design of a 1.5 s high quality microgravity\n   drop tower facility","type":"article-journal","username":"hermann","version":"","volume":"129"}}