Parametric study thickness

Probably the first major publication of a process model for the autoclave curing process is one by Springer and Loos [14]. Their model is still the basis, in structure if not in detail, for many autoclave cure models. There is little information about results obtained by the use of this model only instructions on how to use it for trial and error cure cycle development. Lee [16], however, used a very similar model, modified to run on a personal computer, to do a parametric study on variables affecting the autoclave cure. A cure model developed by Pursley was used by Kays in parametric studies for thick graphite epoxy laminates [18]. Quantitative data on the reduction in cure cycle time obtained by Kays was not available, but he did achieve about a 25 percent reduction in cycle time for thick laminates based on historical experience. A model developed by Dave et al. [17] was used to do parametric studies and develop general rules for the prevention of voids in composites. Although the value of this sort of information is difficult to assess, especially without production trials, there is a potential impact on rejection rates. 

The internal diffusion effects cannot be simply included into the reaction kinetics particularly in the case of parametric studies on the varying washcoat thickness. 

Parametric studies of the effects of TMP, temperature and crossflow velocity on the permeate flux and protein retention rate have been conducted using 0.8 pm alumina membranes at a pH of 4.4. The maximum steady state flux is observed at a TMP of 3 bars. As expected, a higher crossflow velocity increases the steady state permeate flux, as illustrated in Figure 6.3 under the condition of 50 C, TMP of 5 bars and pH of 4.40 [Attia et al., 1991b]. The protein retention rate also improves with the inciease in the crossflow velocity. The permeate flux reaches 175 L/hr-m, accompanied by a protein retention rate of 97.5% when the crossflow velocity is at 3.8 m/s. This improvement in the flux corresponds to a reduction in the thickness of the external fouling layer. 

The properties which determine heat transfer through a deposit layer of given thickness are thermal conductivity, emissivity, and absorptivity. These properties vary with deposit temperature, thermal history, and chemical composition. Parametric studies and calculations for existing boilers were carried out to show the sensitivity of overall furnace performance, local temperature, and heat flux distributions to these properties in large p.f. fired furnaces. The property values used cover the range of recent experimental studies. Calculations for actual boilers were carried out with a comprehensive 3-D Monte Carlo type heat transfer model. Some predictions are compared to full-scale boiler measurements. The calculations show that the effective conduction coefficient (k/As)eff of wall deposits strongly influences furnace exit temperatures. 

Parametric Study. A study of the effect of process parameters on the deposition of boron using the static filament apparatus was conducted. The parameters studied include system pressure, reactant gas flow, ratios, electrode separation, and configurations, and field strengths. The evaluation of certain parameters has been quantitative and was based on the weight of boron deposited or on the thickness of the deposit at the midpoint of the filament. Other parameters were evaluated by a qualitative description of the deposit. 

The parametric study shows that column thickness and bolt sizes are the main key factors that influence the moment resistance and initial stiffness of the connections. 

Beming et al. [58] performed a parametric study using their previously described singlephase, three-dimensional model [55]. The effect of various operational parameters such as the temperature and pressure on the fuel cell performance was investigated. In addition, geometrical and material parameters such as the gas diffusion electrode thickness and porosity as well as the ratio between the channel width and the land area were investigated. It was found that in order to obtain physically realistic results experimental measurements of various modeling parameters were needed. In addition, the contact resistance inside the cell was found to play an important role for the evaluation of impact of such parameters on the fuel cell performance. The impact of liquid water on transport in the gas-diffusion electrode was, however, not account for. 

Parametric studies on two kinds of electrodes for circle-shaped diaphragms with a radius of 10 mm were conducted with the material properties and thicknesses shown in Table 9.2 [3]. The material properties E and dsj of the IPMC in Li" form were determined thorough the equivalent bimorph beam model [28]. The elastic modulus of Nafion in Li form and Poisson s ratios were obtained from literature [32, 33]. Figure 9.10 shows the shape of the two electrodes in a one-quarter finite element model of diaphragms. Figure 9.10a is the circle-shaped electrode and 9.10b is the ring-shaped electrode. 

Data from this ring parametric study is plotted In Fig. 13. The effect of changing ring weight on oil delivery Is illustrated In Fig. 13(a) for the case of the llAmn ring (Type 4). This was accomplished with rings of different radial thickness (b) ie. 3.3mn, 6.4gm and... 

In the previous finite element parametric study of cracked steel plate with CFRP patching, the material properties of the 1.2-mm-thick CFRP plate (Sika, 2003) were assigned for the CFRP patching. In order to compare results of the plate model and the tube model, the same material properties of the CFRP plate were assigned for... 

A parametric study is important for the optimization of the CRS. Those conducted here are aimed directly at the FRPC material where thickness, fiber type, and wrap orientation are considered and are based on the cases of individual static loading as well as the combined static loadings of internal pressure, tension and bending moment. 

While the resulting model is not quantitatively predictive, important observations can be made based on parametric simulation studies. It is proposed that changes in viscosity due to wafer temperature may be as large as 30%, and that such viscosity dependencies can have significant impact on fluid film thickness and transitively on removal rate. The importance of other process parameters, such as wafer curvature, is also indicated by the model. 

The femtosecond transient absorption studies were performed with 387 nm laser pulses (1 khz, 150 fs pulse width) from an amplified Ti Sapphire laser system (Model CPA 2101, Clark-MXR Inc). A NOPA optical parametric converter was used to generate ultrashort tunable visible pulses from the pump pulses. The apparatus is referred to as a two-beam setup, where the pump pulse is used as excitation source for transient species and the delay of the probe pulse is exactly controlled by an optical delay rail. As probe (white light continuum), a small fraction of pulses stemming from the CPA laser system was focused by a 50 mm lens into a 2-mm thick sapphire disc. A schematic representation of the setup is given below in Fig. 7.2. 2.0 mm quartz cuvettes were used for all measurements. 

All seismically compact W14 and W18 column sections were subsequently studied parametrically Fig. 8 illustrates the relationship developed between column web stiffness and seismic demand for W14 and W18 column sections. An equation for determining the need for continuity plates was formulated by applying a regression analysis to the column data and solving for the web thickness, tew (Adan 2006). Continuity plates are required in W14 columns if the web thickness is less than the value given by ... 

In porous materials, diffusion of a solute is complicated by the geometric constraints of the pore structure. Since they are easily solved, continuum expressions have been used as the basis for many studies of diffusion in porous structures. In most cases, the continuum approach is parametric a numerical value for Deff is selected so that the solution of equation 16 fits a particular set of experimental transport measurements. By this method, correlation between effective diffusion coefficients obtained for different solutes or different porous materials is difficult. In this section, descriptions of porous geometries are used to examine the influence of pore microstructure on effective diffusion coefficients. These descriptions will have value only under certain conditions for example, if the size of a characteristic pore is much less than the thickness of the slab and the pore structure is well connected. 

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