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 共查询到20条相似文献,搜索用时 156 毫秒
1.
THEANALYTICALSTUDYONTHELASERINDUCEDREVERSE-PLUGGINGEFFECTBYUSINGTHECLASSICALELASTICPLATETHEORY(II)──REVERSE-BULGEMOTION¥(周益春,...  相似文献   

2.
THEEXISTENCEOFPERIODICSOLUTIONOFTHEFOURTHORDINARYNONLINEARDIFFERENTIALEQUATIONCAUSEDBYFLOW-INDUCEDVIBRATIONGuQing-fang(顾清芳)Ta...  相似文献   

3.
STUDIES OF MELNIKOV METHOD AND TRANSVERSAL HOMOCLINIC ORBITS IN THE CIRCULAR PLANAR RESTRICTED THREE-BODY PROBLEMZhuRuzeng(朱如...  相似文献   

4.
THEGENERALSOLUTIONFORDYNAMICRESPONSEOFNONHOMOGENEOUSBEAMWITHVARIABLECROSSSECTIONJiZhen-yi(纪振义)(AnhuiArchitecturalIndustryColl...  相似文献   

5.
THECALCULATIONOFTHEMULTIPLY-CONNECTEDELASTICPLANEPROBLEMSBYMEANSOFSTRESSFUNCTIONSOFMULTIPLECOMPLEXVARIABLESwangLindiang(王林江)L...  相似文献   

6.
ANITERATIVEMETHODFORTHEDISCRETEPROBLEMSOFACLASSOFELLIPTICALVARIATIONALINEQUALITIESZhengTie-shens(郑铁生)LiLi(李立)XuQing-yu(许庆余)(D...  相似文献   

7.
SOLUTIONSOFTHEGENERALn-THORDERVARIABLECOEFFICIENTSLINEARDIFFERENCEEQUATIONZhouZhi-hu(周之虎)(AnhuiArchitectureIndustryCollege).H...  相似文献   

8.
THEPROBLEMSOFTHENONLINEARUNSYMMETRICALBENDINGFORCYLINDRICALLYORTHOTROPICCIRCULARPLATE(I)QinSheng-Ii(秦圣立)HuangJia-yin(黄家寅)(Quf...  相似文献   

9.
THECALCULATIONOFEIGENVALUESFORTHESTATIONARYPERTURBATIONOFCOUETTE-POlSEUILLEFLOWSongJinbao(宋金宝)ChenJianning(陈建宁)(ReceivedDec.3...  相似文献   

10.
THEINTERACTIONOFPLANESH-WAVESANDCIRCULARCAVITYSURFACEDWITHLININGINANISOTBOPICMEDIAHanFeng(韩峰)Weiyang(韦扬)LiuDiankui(刘殿魁)(Recei...  相似文献   

11.
THESTRESSANALYSISOFVESSELWALLINTHEENTRANCEREGIONOFATAPEREDVESSELCenRen-Jing(岑人经)TanZhe-dong(谭哲东)ChenZheng-zong(陈正宗)(SouthChin...  相似文献   

12.
The correlation problem between the blood flow and the motion of vessel wall in the mammalian circulatory system is discussed in this paper. Supposing the blood flow is under the stable oscillatory condition, a set of formulas for velocity distribution, pressure distribution, displacement of vessel wall and constraining stress are obtained. Kuchar’s formulas are extended from steady flow to unsteady oscillatory flow by means of the formulas obtained in this paper. The problem of elasticity effect of vessel wall is also discussed.  相似文献   

13.
Assuming that the tapered angle is small,the problems of developing flow under unsteady oscillatory condition are studied in this paper.The formula of velocity distribution is obtained.The analyses for the results show that the blood flow in a converging tapered vessel remains a developing flow throughout the length,and the effects of tapered angle on the developing flow are increased with the increment of the tapered angle.  相似文献   

14.
We study the flow of a viscous fluid through a slender tapered tube whose radius may reduce to zero. The vessel is closed at the end, so that the flow is made possible owing to the fact that a portion of the tube wall is permeable. The smallness of the tube aspect ratio is exploited using an upscaling technique leading to a degenerate differential equation for pressure. Solutions are found either in explicit form or as power series expansions. This class of flows may represent, though in a largely approximated way, the blood flow though a coronary artery.  相似文献   

15.
The quasi-one-dimensional Newtonian fluid flow in an active vessel in which the inlet pressure oscillates about a mean value is considered. The vascular wall is assumed to display the Bayliss effect and a reaction to changes in blood flow. The first is characterized by the dependence of the contractility of the vascular smooth-muscle cells on the intravascular pressure and the second by the sensitivity of the endothelial cells to the wall shear stress. The dependence of the period-average radius and blood flow rate on the mean value and pulsation amplitude and frequency of the inlet pressure is investigated numerically. The characteristics are compared for the passive vessel, the vessel with the Bayliss effect, and the vessel with both reactions.  相似文献   

16.
An analysis model of pulsatile blood flow in arteries   总被引:3,自引:0,他引:3  
IntroductionTheperiodicallypulsatilebloodflowinthearterycausesthecircumferentialandaxialmotionoftheelasticbloodvesselandinturntheoscillationofthevesselaffectsthatofthebloodflow .Womersley[1]resolvedsuccessfullythisfluid_solidcouplingproblembysolvingbothlinearNavier_Stokesequationsandthemotionequationsofthethin_walledelastictubeandgainedtheexpressionsofthebloodflowvelocitiesandthevasculardisplacements.Histheoryhasbeenthebasisforthequantitativeanalysisoftherelationshipofthearterialstructureandi…  相似文献   

17.
The flow in a vessel able to regulate its lumen under the action of mechanical stimuli, the variation of the pressure difference between the inner and outer surfaces of the vessel wall and the blood flow velocity, is described. This ability is determined by the effect of the mechanical stimuli on the degree of activation of smooth muscle cells in the vessel wall. In order to describe the active properties of the wall, two controlling parameters which have the sense of the concentration of free calcium ions in the cytoplasm of smooth muscle cells and the average concentration of nitric oxide in the smooth muscle layer, are introduced. The approach proposed makes it possible to estimate both the degree of participation of each mechanical stimulus in vessel lumen regulation and the result of interaction of two differently directed vascular responses. The calculations show that both the magnitude and direction of the radius response to a mechanical stimulus depend on the initial state of the vessel wall. The role of the vessel wall sensitivity to mechanical stimuli in the stabilization of the blood flow-rate and the variation of the radius along the vessel is considered.  相似文献   

18.
Ali  A.  Hussain  M.  Anwar  M. S.  Inc  M. 《应用数学和力学(英文版)》2021,42(11):1675-1684

In this study, a mathematical model is formulated to examine the blood flow through a cylindrical stenosed blood vessel. The stenosis disease is caused because of the abnormal narrowing of flow in the body. This narrowing causes serious health issues like heart attack and may decrease blood flow in the blood vessel. Mathematical modeling helps us analyze such issues. A mathematical model is considered in this study to explore the blood flow in a stenosis artery and is solved numerically with the finite difference method. The artery is an elastic cylindrical tube containing blood defined as a viscoelastic fluid. A complete parametric analysis has been done for the flow velocity to clarify the applicability of the defined problem. Moreover, the flow characteristics such as the impedance, the wall shear stress in the stenotic region, the shear stresses in the throat of the stenosis and at the critical stenosis height are discussed. The obtained results show that the intensity of the stenosis occurs mostly at the highest narrowing areas compared with all other areas of the vessel, which has a direct impact on the wall shear stress. It is also observed that the resistive impedance and wall shear pressure get the maximum values at the critical height of the stenosis.

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19.
Estimates are presented for the effect of susceptibility of the inner surface of the blood vessel wall to shear stress on changes in diameter and volume blood flow rate. The model of thin-walled vessel with radius controlled by two parameters is used. The effect of rheological factors, hematocrit, and oxygen content in blood on the value of vessel response to a change in shear stress is considered. The estimates showed that the contribution of the vessel response in question to a change in blood volume flow rate amounts tens per cent. The influence of rheological (Fahraeus and Fahraeus-Lindqvist) effects on flow rate lies within several per cent. The role of the vessel response considered increases with anaemia: at low hematocrit its contribution to increase in flow rate exceeds 10%. Variation of oxygen concentration within the normal range has almost no effect on the hemodynamic parameters. With hypoxia, on the contrary, the participation of this response on changes in flow rate weakens: in severe hypoxia decrease in blood flow rate owing to a change in oxygen concentration equals approximately 9%.  相似文献   

20.
The problem of non-Newtonian and nonlinear blood flow through a stenosed artery is solved numerically where the non-Newtonian rheology of the flowing blood is characterised by the generalised Power-law model. An improved shape of the time-variant stenosis present in the tapered arterial lumen is given mathematically in order to update resemblance to the in vivo situation. The vascular wall deformability is taken to be elastic (moving wall), however a comparison has been made with nonlinear visco-elastic wall motion. Finite difference scheme has been used to solve the unsteady nonlinear Navier-Stokes equations in cylindrical coordinates system governing flow assuming axial symmetry under laminar flow condition so that the problem effectively becomes two-dimensional. The present analytical treatment bears the potential to calculate the rate of flow, the resistive impedance and the wall shear stress with minor significance of computational complexity by exploiting the appropriate physically realistic prescribed conditions. The model is also employed to study the effects of the taper angle, wall deformation, severity of the stenosis within its fixed length, steeper stenosis of the same severity, nonlinearity and non-Newtonian rheology of the flowing blood on the flow field. An extensive quantitative analysis is performed through numerical computations of the desired quantities having physiological relevance through their graphical representations so as to validate the applicability of the present model.  相似文献   

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