1、Designation:D 2507 93Standard Terminology ofRheological Properties of Gelled Rocket Propellants1This standard is issued under the fixed designation D 2507;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A nu
2、mber in parentheses indicates the year of last reapproval.Asuperscript epsilon(e)indicates an editorial change since the last revision or reapproval.1.Scope1.1 These definitions2cover the flow properties of gelledpropellants of interest to the aerospace industry.2.Terminology2.1 Definitions:apparent
3、 viscosity(of a non-Newtonian fluid)the viscos-ity of a Newtonian fluid that produces the same reading inthe same apparatus under identical conditions.DiscussionAvoidance of this artificial term is recom-mended.classification of fluids:Class INewtonian Fluid a fluid that exhibits a directproportiona
4、lity between shear stress and shear rate in theregion of laminar flow.DISCUSSIONThe shear rate is independent of the time of applicationof shear stress.Class IINon-Newtonian Shear-Thinning Fluida fluid inwhich the shear stress is not directly proportional to the shearrate and in which the shear stre
5、ss-shear rate ratio decreasesas the shear stress increases.(a)Type APlastic Fluida Class II fluid that exhibits achange in shear rate directly proportional to the change in shearstress above the yield stress.(b)Type BPseudoplastic Fluida Class II fluid thatexhibits a shear stress-shear rate ratio th
6、at is independent of theduration of application of shear stress.(c)Type CThixotropic Fluida Class II fluid thatexhibits time-dependent,reversible changes of the shear stress-shear rate ratio.DiscussionThe ratio decreases asymptotically with dura-tion of shear.Class IIINon-Newtonian Shear-Thickening
7、Fluidafluid in which the shear stress is not directly proportional tothe shear rates,and in which the shear stress-shear rate ratioincreases as the shear stress increases.(a)Type ADilatant Fluida Class III fluid that exhibitsa shear stress-shear rate ratio that is independent of the durationof appli
8、cation of shear stress.(b)Type BRheopectic FluidA Class III fluid thatexhibits time-dependent,reversible changes of the shear stress-shear rate ratio.DiscussionThe ratio increases asymptotically with dura-tion of shear.emulsiona two-phase liquid system in which small dropletsof one liquid(the intern
9、al phase)are immiscible in,and aredispersed uniformly throughout,a second,continuous liquidphase(the external phase).gela liquid containing a colloidal structural network thatforms a continuous matrix and completely pervades theliquid phase.DiscussionA gel deforms elastically upon application ofshea
10、r forces less than the yield stress.At shear forces above theyield stress,the flow properties are principally determined bythe gel matrix.viscositythe ratio of shear stress to shear rate.For non-Newtonian fluids,it is preferable to report shear stress andshear rate.DiscussionIf the viscosity of such
11、 a fluid is reported,theshear rate must be specified.yield stressthe maximum shear stress that can be appliedwithout causing permanent deformation.3.Keywords3.1 terminology,Dilanant fluid;terminology,Newtonianfluid;terminology,Non-Newtonian fluid;terminology,plasticfluid;terminology,propellants;term
12、inology,Rheopectic fluid;terminology,Thixotropic fluid;terminology,yield stress1These definitions are under the jurisdiction of ASTM Committee F-7 onAerospace Industry Methods and are the direct responsibility of SubcommitteeF07.02 on Propellant Technology.Current edition approved March 15,1993.Publ
13、ished May 1993.Originallypublished as D 2507 66 T.Last previous edition D 2507 70(1983).2These definitions are identical in substance with the JANNAF definitions,“AGlossary of Rheological Terms,”Part I of“Heterogeneous Propellant Characteriza-tion,”Liquid Propellant Test Methods,March 1967,published
14、 by the ChemicalPropulsion Information Agency,Johns Hopkins University,Applied Physics Labo-ratory,Johns Hopkins Rd.,Laurel,MD 20707.1Copyright ASTM,100 Barr Harbor Drive,West Conshohocken,PA 19428-2959,United States.The American Society for Testing and Materials takes no position respecting the val
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16、t to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised,either reapproved or withdrawn.Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM Headquarters.Your comments will receive careful consideration at a meeting of the responsibletechnical committee,which you may attend.If you feel that your comments have not received a fair hearing you should make yourviews kn
