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The Theory used in ADINA is richly documented in the following books by K.J. Bathe and co-authors



To Enrich Life
(Sample pages here)

Following are more than 700 publications — that we know of — with reference to the use of ADINA. Since there are numerous papers published in renowned journals, we can only give here a selection. The pages give the Abstracts of some papers published since 1986 referring to ADINA. The most recent papers are listed first. All these papers may be searched using the box:

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A Mathematical Simulation of the Ureter: Effects of the Model Parameters on Ureteral Pressure/Flow Relations

B.Vahidi1, N. Fatouraee1, A. Imanparast1, and A.N. Moghadam1,2,3

1 Biological Fluid Mechanics Research Laboratory, Department of Biomedical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Haafez Avenue, Tehran, Iran 15914
2 Department of Radiology, Division of Diagnostic Cardiovascular Imaging, David Geffen School of Medicine at the University of California at Los Angeles, Los Angeles, California
3 Department of Bioengineering, California Institute of Technology, Pasadena, California

Journal of Biomechanical Engineering, doi:10.1115/1.4003316, 2010

Abstract: Ureteral peristaltic mechanism facilitates urine transport from the kidney to the bladder. Numerical analysis of the peristaltic flow in the ureter aims to further our understanding of the reflux phenomenon and other ureteral abnormalities. Fluid-structure interaction (FSI) plays an important role in accuracy of this approach and the Arbitrary Lagrangian-Eulerian (ALE) formulation is a strong method to analyze the coupled fluid-structure interaction between the compliant wall and the surrounding fluid. This formulation, however, was not used in previous studies of peristalsis in living organisms. In the present investigation, a numerical simulation is introduced and solved through ALE formulation to perform the ureteral flow and stress analysis. The incompressible Navier-Stokes equations are used as the governing equations for the fluid and a linear elastic model is utilized for the compliant wall. The wall stimulation is modeled by nonlinear contact analysis using a rigid contact surface since an appropriate model for simulation of ureteral peristalsis needs to contain cell-to-cell wall stimulation. In contrast to previous studies, the wall displacements are not pre-determined in the presented model of this finite-length compliant tube, neither the peristalsis needs to be periodic. Moreover, the temporal changes of ureteral wall intraluminal shear stress during peristalsis are included in our study. Iterative computing of two-way coupling is used to solve the governing equations. Two phases of non-peristaltic and peristaltic transport of urine in the ureter are discussed. Results are obtained following an analysis of the effects of the ureteral wall compliance, pressure difference between the ureteral inlet and outlet, maximum height of the contraction wave, the contraction wave velocity and the number of contraction waves on the ureteral outlet flow. The results indicate that the proximal part of the ureter is prone to a higher shear stress during peristalsis compared to its middle and distal parts. It is also shown that the peristalsis is more efficient as the maximum height of the contraction wave increases. Finally, it is concluded that improper function of ureteropelvic junction results in the passage of part of urine back flow even in the case of slow start-up of the peristaltic contraction wave.

Keywords: Peristalsis - vesicoureteral reflux - Arbitrary Lagrangian-Eulerian formulation - FSI method

Modal analysis for filament wound pressure vessels filled with fluid

Z. Wu1, W. Zhou2, H. Li2

1 State Key Laboratory of Structural Analysis for Industrial Equipment, Dalian University of Technology, Dalian 116024, China
2 School of Civil Engineering, Harbin Institute of Technology, 202 Haihe Road, Nan’gang District, Harbin 150090, China

Composite Structures (In press 2010)

Abstract: Filament wound pressure vessels have been extensively used in many engineering fields, especially aerospace industry. Vibration-based damage detection methods have the potential to be employed to monitor the health status of the structures based on the fact that damage occurred in a structure would result in changes in its structural dynamic characteristics. However the presence of fluid will affect the dynamic response of this type of vessel structures. Due to the liquid mass decrease during its service, the whole system is considered a time-variant system in terms of its dynamic response even the structure itself remains free of damage, which cause problems for vibration-based damage detection method that utilized dynamic response change to identify damage. Therefore it is critical to understand how the change of the liquid height level influences the dynamic response of the coupled fluid–structure system. This work describes the FEM analysis and an experimental study on the dynamic response of filament wound pressure vessels filled  with liquid of different heights and provides the primary information that can be used for vibration-based damage detection.

Keywords: Modal analysis - Experiment - FEM - Filament wound vessel - FSI


Damage analysis of a steel-concrete composite frame by finite element model updating

G. Chellinia, G. De Roeckb, L. Nardinia, W. Salvatorea

aDepartment of Civil Engineering, University of Pisa, Largo Lucio Lazzarino 1, 56126 Pisa, Italy
bDepartment of Civil Engineering, Catholic University of Leuven, Kasteelpark Arenberg 40, B-3001 Heverlee, Belgium

Journal of Constructional Steel Research 66 (2010) 398-411

Abstract: In the last two decades, many studies have reported the effectiveness of Experimental Modal Analysis and Finite Element Model Updating in mechanical and aerospace engineering, where they represent useful tools for Structural Health recognition and can provide an information base for detection, assessment and quantification of structural damage due to exercise actions and exceptional events.
The applications of Damage Detection techniques to civil constructions left some still not well clarified points, due to the great variety of structural typologies, material properties, boundary conditions and possible damage patterns, as in the case of seismic damage. In order to design post-earthquake rehabilitation interventions, in fact a careful knowledge of the damage distribution and residual structural capacity is obviously needed and this can be very expensive and time consuming. However, the application of vibration based damage identification techniques to high ductile structures designed according to seismic capacity approach can improve the feasibility, reliability and efficiency of these methods. In the present study, Finite Element Model Updating procedures based on vibration measurements were used to detect, assess and quantify the structural damage of a high ductile steel_concrete composite frame subjected to increasing seismic damage by means of pseudo dynamic and cyclic test at the Joint Research Centre (Ispra, Italy). The updating process, repeated for three damage levels, has been applied to different finite element structural models (addressing different modelling strategies), allowing a comprehensive description and quantification of the progressive degradation of beam-to-column joints, devoted to dissipate the seismic energy by design.

Keywords: Steel-concrete composite frame - Joint stiffness - Model updating - Damage detection - Finite element modelling


Fluid–structure interaction in aortic cross-clamping: Implications for vessel injury

H.Y.Chena,e, J.A. Naviab, S. Shafiqued, G.S. Kassaba,c,d,e,f

aWeldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47907, USA
bDepartment of Cardiovascular Surgery, Austral University, Buenos Aires 1011, Argentina
cDepartment of Biomedical Engineering, IUPUI, Indianapolis, IN 46202, USA
dSurgery, IUPUI, Indianapolis, IN 46202, USA
eDepartment of Cellular and Integrative Physiology, IUPUI, Indianapolis, IN 46202, USA
fIndiana Center for Vascular Biology and Medicine, IUPUI, Indianapolis, IN 46202, USA

Journal of Biomechanics, Volume 43, Issue 2, Pages 221-227, 2010

Abstract: Vascular cross-clamping is applied in many cardio vascular surgeries such as coronary bypass, aorta repair and valve procedures. Experimental studies have found that clamping of various degrees caused damage to arteries. This study examines the effects of popular clamps on vessel wall. Models of the aorta and clamp were created in Computer Assisted Design and Finite Element Analysis packages. The vessel wall was considered as a non-linear anisotropic material while the fluid was simulated as Newtonian with pulsatile flow. The clamp was applied through displacement time function. Fully coupled two-way solid–fluid interaction models were developed. It was found that the clamp design significantly affected the stresses in vessel wall. The clamp with a protrusion feature increased the overall Von Mises stress by about 60% and the compressive stress by more than 200%. Interestingly, when the protrusion clamp was applied, the Von Mises stress at the lumen (endothelium) side of artery wall was about twice that of the outer wall. This ratio was much higher than that of the plate-like clamp which was about 1.3. The flow reversal process was demonstrated during clamping. Vibrations, flow and wall shear stress oscillations were detected immediately before total vessel occlusion. The commonly used protrusion clamp increased stresses in vessel wall, especially the compressive stress. This design also significantly increased the stresses on endothelium, detrimental to vessel health. The present findings are relevant to surgical clamp design as well as the transient mechanical loading on the endothelium and potential injury. The deformation and stress analysis may provide valuable insights into the mode of tissue injury during cross-clamping.

Keywords:Fluid–structure interaction - Surgical clamp designs - Intramural wall stress - Wall shear stress - Endothelium


Multi-scale design simulation of a novel intermediate-temperature micro solid oxide fuel cell stack system

S.F. Lee, C.W. Hong

Department of Power Mechanical Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan

Int. J. of Hydrogen Energy (In press, 2010)

Abstract: This paper presents a multi-scale simulation technique for designing a novel intermediatetemperature planar-type micro solid oxide fuel cell (mSOFC) stack system. This multi-scale technique integrates the fundamentals of molecular dynamics (MD) and computational fluid dynamics (CFD). MD simulations are carried out to determine the optimal composition of a potential electrolyte that is capable of operation in the intermediate-temperature region without sacrifice in performance. A commercial CFD package plus a self-written computational electrochemistry code are employed to design the fuel and air flow systems in a planar five-cell stack, including the preheating manifold. Different samarium-doped ceria (SDC) electrolyte compositions and operating temperatures from 673 K to 1023 K are investigated to identify the maximum ionic conductivity. The electrochemical performance simulation using an available 5-cell yittria-stablized-zirconia (YSZ) mSOFC stack
shows good agreement with our experimental results. The same stack design is used to predict a novel SDC-mSOFC performance. Feasibiulity studies of this intermediate-temperature stack are presented using this multi-scale technique.

Keywords: Micro solid oxide fuel cell - Multi-scale simulation - Molecular dynamics - Computational fluid dynamics


Assessment of potential-based fluid finite elements for seismic analysis of dam–reservoir systems

N. Bouaanani, F.Y. Lu

Department of Civil, Geological and Mining Engineering, École Polytechnique de Montréal, Montréal, QC, Canada H3C 3A7

Computers and Structures 87 (2009) 206–224

Abstract: This paper assesses the use of a potential-based fluid finite element formulation to investigate earthquake excited dam–reservoir systems. The mathematical background of the analytical and numerical techniques is presented in a uni.ed format. Frequency and time-domain analyses are conducted to validate the potential-based finite element formulation. A case study of a typical dam–reservoir system subjected to earthquake loading is presented. The dynamic response of the system is discussed to illustrate the effects of fluid–structure interaction and reservoir bottom absorption. The validated potential-based fluid elements and boundary conditions are shown to perform adequately for practical seismic analysis of dam–reservoir systems.

Keywords: Finite elements - Fluid–structure interaction - Dam safety - Earthquake engineering - Frequency-domain response - Time-domain response


Nonlinear fluid–structure interaction calculation of the leakage behaviour of cracked concrete walls

C. Niklascha, N. Herrmannb

aEd. Züblin AG, Technical Head Office, Tunnel Engineering Department, Albstadtweg 3, 70567 Stuttgart, Germany
bMaterials Testing and Research Institute (MPA Karlsruhe), Universität Karlsruhe (TH), 76128 Karlsruhe, Germany

Nuclear Engineering and Design 239 (2009) 1628–1640

Abstract: In the case of severe accidents in nuclear power plants, containments are the last barrier to prevent the release of environmentally hazardous substances. Therefore, the leaktightness of the containment is of decisive importance for the safety and protection of the environment in case of an accident. A numerical model based on the Finite Element Method has been developed to calculate the leakage behaviour of reinforced concrete walls. Leakage flow and structural response are solved iteratively. For the calculation of the leakage flow a fluid model has been used which takes into account the condensation of the steam part within the air–steam mixture. Both, the release of the latent heat in the case of condensation and the following two-phase flow of air and water have been considered, too. Tests with the SIMIBE Experimental facility [Caroli, C., Coulon, N., Renson, C., 1995. Steam leakage through concrete cracks: parametric study with SIMIBE experiment and interpretation of the results. Tech. Rep. Commissariat A L’Energie Atomique (CEA)] are used for verification of the condensation and two-phase flow models.


Modeling and optimizing passive valve designs for the implantable Gold Micro-Shunt used in glaucoma treatment

J.L. Lin, J.M. Clevenger

SOLX, Inc., 890 Winter Street, Suite 115, Waltham, MA 02451, USA

Computers and Structures 87 (2009) 664–669

Abstract: Glaucoma is an age-related eye disease that causes ocular nerve damage, typically characterized by elevated intraocular pressure (IOP). Studies have shown that IOP can vary significantly on the order of days or even hours. Failure to control IOP spikes in this time-frame can lead to irreversible damage to the optic nerve and blindness. The proposed drainage device combines a passive check-valve with the implantable Gold Micro-Shunt to regulate flow based on changing IOP. Using finite element analysis, we examined the mechanical behavior of different valve designs and their flow characteristics. Two designs were found to provide desirable flow resistance.

Keywords: Glaucoma - Intraocular pressure - MEMS - Check-valve - Drainage device - Finite element analysis


A numerical investigation of waves propagating in the spinal cord and subarachnoid space in the presence of a syrinx

C.D. Bertram

Biofluid Mechanics Laboratory, Faculty of Engineering, University of New South Wales, Sydney 2052, Australia

Journal of Fluids and Structures 25 (2009) 1189–1205

Abstract: The term syringomyelia describes fluid-filled cavities in the spinal cord, which can interfere with normal nerve signal transmission. The finite-element code ADINA was used to construct an axisymmetric fluid/structure-interaction model of the tapered spinal cord and subarachnoidspace(SAS), bounded by the dura mater. A syrinx was simulated, of corresponding dimensions to one shown by magnetic resonance imaging data of a patient with syringomyelia. The model was used to investigate the clinical hypothesis that SAS pressure waves move fluid along a syrinx and can thus lengthen it over time by tissue dissection. Simplified versions of the model were used to examine in detail the waves excited, and their reflection and refraction at sites of property discontinuity in the system. Comparison was made with wave predictions based on an analytical model, and excellent agreement was found. The results suggest that, under the circumstances modelled, pressure wave-induced motion of syrinx fluid is unlikely to lengthen such cavities, unless the transverse tensile strength of cord tissue is even smaller than has been appreciated so far.

Keywords: Syringomyelia - Fluid–structure interaction - Wave transmission - Chiari malformation - Cerebrospinal fluid


Numerical simulation of fluid–structure interaction in stenotic arteries considering two layer nonlinear anisotropic structural model

A. Valencia, F. Baeza

Department of Mechanical Engineering, Universidad de Chile, Casilla 2777, Santiago, Chile

International Communications in Heat and Mass Transfer 36 (2009) 137–142

Abstract: The unsteady non-Newtonian blood flow in symmetric stenotic arteries is numerically simulated considering fluid–structure interaction (FSI) using the code ADINA. A two layer hyperelastic anisotropic structural model is used for the compliant arterial wall. The pressure used as outlet boundary condition was obtained running a CFD simulation for each stenosis with a physiologically-realistic time variation of pressure at inlet for different velocities. The obtained pressure drop increases in potential form with the inlet velocity for a fixed stenosis severity. The FSI results show that the maxima velocity and WSS at throat increase in exponential form with stenosis severity. The minimum and maximum effective stress at throat for stenosis severity of S=70% ranged between 47 kPa and 96 kPa at diastole and systole, respectively.

Keywords: CFD - FSI - WSS - Anisotropic artery - Stenosis - Blood flow - Effective stress


Contact interface in seismic analysis of circular tunnels

H. Sedarata, A. Kozaka, Y.M.A. Hashashb, A. Shamsabadic, A. Krimotata

aSC Solutions, 1261 Oakmead Parkway, Sunnyvale, CA 94085, USA
bUniversity of Illinois at Urbana-Champaign, 205 N. Mathews Ave., Urbana, IL 61801, USA
bCaltrans, Department of Transportation, State of California, 3 Mayapple Way, Irvine, CA 92612, USA

Tunnelling and Underground Space Technology 24 (2009) 482–490

Abstract: The seismic analysis of underground structures requires a careful consideration of the important effect of shear strains in the soil due to vertically propagating horizontal shear waves. These strains result in ovaling deformations of circular tunnels or racking deformations of rectangular tunnels. Closed-form solutions as well as numerical analyses are used to characterize this soil-structure interaction problem. Many of these solutions assume full normal contact at the interface between the soil and tunnel lining. This work describes a numerical finite element study of soil-circular tunnel lining interaction with contact conditions that allow both limited slippage and separation to prevent development of potentially unrealistic normal tensile and tangential forces at the interface. The analyses highlight the significant limitations of widely used closed-form solutions in engineering practice. The finite element solutions demonstrate the need for realistic representation of the soil-tunnel interaction using numerical modeling approaches.

Keywords: Seismic analysis - Soil-tunnel interaction - Frictional contact - Underground structures


An impedance sensor to monitor and control cerebral ventricular volume

A. Linningera, S. Basatia, R. Dawea, R. Pennb

aLaboratory for Product and Process Design (LPPD), Department of Bioengineering, University of Illinois at Chicago, Chicago, IL 60607, United States
bDepartment of Neurosurgery, University of Chicago, Chicago, IL 60637, United States

Medical Engineering & Physics 31 (2009) 838–845

Abstract: This paper presents a sensor for monitoring and controlling the volume of the cerebrospinal flulid-filledventricles of the brain. The measurement principle of the sensor exploits electrical conductivity differences between the cerebrospinal flulid and the brain tissue. The electrical contrastwas validated using dog brain tissue. Experiments with prototype sensors accurately measured the volume content of elastically deformable membranes and gel phantoms with conductivity properties made to match human brain. The sensor was incorporated into a fully automatic feedback control system designed to maintain the ventricular volume at normal levels. The experimental conductivity properties were also used to assess the sensor performance in a simulated case of hydrocephalus. The computer analysis predicted voltage drops over the entire range of ventricular size changes with acceptable positional dependence of the sensor electrodes inside the ventricular space. These promising experimental and computational results of the novel impedance sensor with feedbackmay serve as the foundation for improved therapeutic options for hydrocephalic patients relying on volume sensing, monitoring or active feedback control.

Keywords: Cerebrospinal flulid - CSF - Pressure shunts - Volume sensor - Hydrocephalus


SCF analysis of a pressurized vessel–nozzle intersection with wall thinning damage

M. Qadir, D. Redekop

Department of Mechanical Engineering, University of Ottawa, Ottawa, Canada K1N 6N5

International Journal of Pressure Vessels and Piping, 86:541–549, 2009.

Abstract: A three-dimensional finite element analysis is carried out of a pressurized vessel–nozzle intersection (tee joint), with wall thinning damage. A convergence-validation study is first carried out for undamaged intersections, in which comparisons are made with previously published work for the stress concentration factor (SCF), and good agreement is observed. A study is then carried out for specific tee joints to examine the effect on the SCF of varying the extent of the wall thinning damage. Finally, a parametric study is conducted in which the SCF is computed for a wide range of tee joints, initially considered undamaged, and then with wall thinning damage.

Keywords: Finite elements - Tee joint - Stress concentration - Wall thinning


Complex Analysis And Evaluation Of The Condition Of Reinforced-Concrete Components In Power-Generating Structures

V. B. Nikolaev and D. N. Olimpiev

Scientific and Technical Center for Structures, Components, and Construction Materials, Moscow, Russia.

Power Technology and Engineering, 43(5):280-286, 2009.

Abstract: A procedure is proposed for analysis of reinforced-concrete slabs and shells.


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