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Injection Experiment (injection + experiment)
Selected AbstractsRandom discontinuous carbon fiber preforms: Experimental permeability characterization and local modelingPOLYMER COMPOSITES, Issue 4 2010A. Endruweit Injection experiments indicate that for random discontinuous carbon fiber preforms, increasingly uneven flow fronts develop with increasing fiber bundle length and filament count. While at high propensity for fiber bundle splitting, the preform permeability increases continuously with increasing fiber length, no trend can be identified at low propensity. No clear influence of the virgin bundle filament count on the preform permeability was observed. Types of sizing used on the fibers and bundle cross-sectional shapes may vary and affect the intrinsic filamentization behavior, thus dominating the preform permeability. In a model for local preform permeability, interbundle voids, distributed randomly across the preform thickness, are approximated via a regular void structure. Simulated filling patterns are qualitatively similar to those observed experimentally, showing more pronounced features than those derived from a model based on local through-thickness homogenization of the filament distribution. A model based on an alternating arrangement of fiber bundles and voids allows prediction of global preform permeability values from series of injection simulations, showing quantitatively better agreement with corresponding experimental results than the homogenization model. For global permeability, agreement between simulated and experimental mean values improves with increasing fiber volume fraction, whereas calculated coefficients of variation show no strong dependence on the fiber volume fraction. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers [source] Fluid injection and surface deformation at the KTB location: modelling of expected tilt effectsGEOFLUIDS (ELECTRONIC), Issue 1 2005T. JAHR Abstract This investigation is indented to explore the relationship between changes in pore fluid pressure and deformation of the land surface induced by a large-scale injection experiment at the KTB site. Deformation will be monitored by ASKANIA borehole tiltmeters at five locations. During the year 2003, a network of borehole tiltmeters was installed, data transmission links established and tested, and recording of tilt data started. Our first main interest was to receive data sets of all stations well before the injection experiment to start in May 2004, to be able to evaluate local site effects. Thus, the separation of injection-induced effects will be more reliable. Principal 3D numerical modelling (poro-elastic modelling and investigations, using the finite element method, FEM) of poro-elastic behaviour showed that significant tilt amplitudes can be expected during controlled fluid injection. Observed deformation will be investigated within the framework of the fluid flow behaviour and resulting deformation. Two models have been used: a coupled hydro geomechanical finite element model (abaqus) and, as a first step, also a multi-layered poro-elastic crust (poel). With the numerical model two effects can be quantified: (i) the deformation of the upper crust (tilt measurements) and (ii) the spatial distribution and the changes of material properties in the KTB area. The main aim of the project is to improve the knowledge of coupled geomechanic,hydraulic processes and to quantify important parameters. Thus, the understanding of fracture-dominated changes of the hydrogeological parameters will be enhanced, geomechanical parameter changes and the heterogeneity of the parameter field quantified. In addition, the induced stress field variation can be explained, which is believed to be mainly responsible for the increase of local seismic activity. Here, we introduce the tiltmeter array at the KTB site, the modelling for a poro-elastic crust and the preliminary FEM modelling. [source] Real-scale miscible grout injection experiment and performance of advection,dispersion,filtration modelINTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 12 2001F. Bouchelaghem Abstract A model was developed, to describe miscible grout propagation in a saturated deformable porous medium, based on Bear's statistical model with spatial volume averaging. In a previous paper, the model was first successfully confronted to one-dimensional laboratory experiments. In the present paper, the numerical model is used to simulate practical grouting operation in a cylindrical injection model. The cylindrical injection model lends itself to study main flow and propagation character istics for a dispersed suspension-type grout, under axisymmetric conditions close to real scale conditions. Comparison between numerical solutions and experimental results is essential to confirm the validity and accuracy of the proposed model from a phenomenological standpoint. The numerical model performances show that the underlying mathematical model constitutes a realistic predictive model reproducing most prominent features during injection of a suspension-type grout into a deformable porous medium. The basic mechanism by which injected miscible grout permeates a soil mass is discussed in detail. Such a tool leads to quality control criteria for grouting on a theoretical basis, which complements existing criteria acquired through engineering practice. Copyright © 2001 John Wiley & Sons, Ltd. [source] Oral vaccination trials with crayfish, Procambarus clarkii, to induce resistance to the white spot syndrome virusAQUACULTURE RESEARCH, Issue 15 2009Fei Zhu Abstract The potential of oral vaccination against white spot syndrome virus (WSSV) in crayfish Procambarus clarkii was investigated. The protective effect of binary ethylenimine (BEI)-inactivated WSSV was tested by oral vaccination, followed by an oral challenge with WSSV. The crayfish fed with feed pellets coated with BEI-inactivated WSSV showed a resistance to WSSV on the seventh day post vaccination (dpv). The relative percentage survival values were 60%, 70% and 75% for the vaccinated once, twice and thrice with inactivated WSSV. Following an intramuscular injection experiment, no mortality was recorded in the inactivated WSSV group and the negative control at 17 days post challenge. The cumulative mortalities in the heated WSSV group and WSSV group were 100%. Shrimp that survived the WSSV challenge on the seventh day after cessation of oral vaccination were positive for the presence of WSSV by a polymerase chain reaction assay specific for WSSV. This result indicated that inactivated WSSV could protect crayfish against WSSV by oral delivery. [source] Ability of stress-related volatiles to attract and induce attacks by Xylosandrus germanus and other ambrosia beetlesAGRICULTURAL AND FOREST ENTOMOLOGY, Issue 2 2010Christopher M. Ranger 1Xylosandrus germanus typically colonizes physiologically-stressed deciduous hosts but it is increasingly being recognized as a key pest of ornamental nursery stock. We tested the attractiveness of common plant stress-related volatiles to ambrosia beetles occupying the nursery agroecosystem, as well as their ability to induce attacks on selected trees. Experiments were conducted in Ohio, U.S.A. 2Stress volatile attractiveness was first assessed by positioning traps baited with acetaldehyde, acetone, ethanol and methanol in ornamental nurseries. Cumulative trap counts confirmed that ethanol was the most attractive stress-related volatile to X. germanus. Methanol-baited traps were slightly attractive to X. germanus, whereas traps baited with acetaldehyde and acetone were not attractive to any ambrosia beetle. 3A series of tree injection experiments were also conducted to determine the ability of these volatiles to induce attacks by ambrosia beetles under field conditions. Injection of ethanol into Magnolia virginiana induced the largest number of attacks, whereas injection of acetaldehyde induced more attacks than methanol or acetone. Xylosandrus germanus was the most predominant species emerging from M. virginiana injected with each of the stress-related volatiles. No attacks by wood-boring beetles were observed on water injected or uninjected control trees. 4Solid-phase microextraction,gas chromatography,mass spectrometry confirmed the emission of acetaldehyde, acetone, ethanol and methanol after their injection into M. virginiana. 5Xylosandrus germanus has an efficient olfactory-based mechanism for differentiating among host volatile cues. Injecting select trees with stress-related volatiles, particularly ethanol, shows promise as a trap tree strategy for X. germanus and other ambrosia beetles. [source] A study of the Coriolis effect on the fluid flow profile in a centrifugal bioreactorBIOTECHNOLOGY PROGRESS, Issue 4 2009Christopher J. Detzel Abstract Increasing demand for tissues, proteins, and antibodies derived from cell culture is necessitating the development and implementation of high cell density bioreactors. A system for studying high density culture is the centrifugal bioreactor (CCBR), which retains cells by increasing settling velocities through system rotation, thereby eliminating diffusional limitations associated with mechanical cell retention devices. This article focuses on the fluid mechanics of the CCBR system by considering Coriolis effects. Such considerations for centrifugal bioprocessing have heretofore been ignored; therefore, a simpler analysis of an empty chamber will be performed. Comparisons are made between numerical simulations and bromophenol blue dye injection experiments. For the non-rotating bioreactor with an inlet velocity of 4.3 cm/s, both the numerical and experimental results show the formation of a teardrop shaped plume of dye following streamlines through the reactor. However, as the reactor is rotated, the simulation predicts the development of vortices and a flow profile dominated by Coriolis forces resulting in the majority of flow up the leading wall of the reactor as dye initially enters the chamber, results are confirmed by experimental observations. As the reactor continues to fill with dye, the simulation predicts dye movement up both walls while experimental observations show the reactor fills with dye from the exit to the inlet. Differences between the simulation and experimental observations can be explained by excessive diffusion required for simulation convergence, and a slight density difference between dyed and un-dyed solutions. Implications of the results on practical bioreactor use are also discussed. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 [source] | ||||||||||