Immersed body method

Immersed Body Method (DIN 53 217 T 3). The density is calculated from the buoyancy of spherical bodies immersed in the paint. This method is used for low- and medium-viscosity paints and is particularly suitable for production control. 

Three techniques related to oscillating-body methods can be mentioned. One involves measuring the torsional oscillations of a piezoelectric crystal immersed in a fluid it can achieve accuracies of about 2% and has been used in a variety of conditions. A second involves measuring the drag on a rotating cylinder magnetically suspended in the fluid it can achieve uncertainties as low as... 

A displacement method is used to determine specific gravity of solid plastics but can also be used to determine specific gravity of hquid using Weld pycnometer and immersion body of known density. ... 

The immersed boundary method is a numerical method in computational fluid dynamics where the flow boundary, e.g., the surface of a solid body in contact with the fluid or the interface between two immiscible fluids, is immersed in the mesh that does not conform with the boundary. In the immersed boundary method, special treatment has to be taken at the boundary to incorporate the boundary conditions. 

In some variants of the immersed boundary method dealing with the boundary between a fluid and a solid body, the fictitious fluid is introduced inside the solid body, and a boundary force, F, in place of Af in Eq. 4, is distributed into the augmented flow field in the same way as described for the fluid-fluid interface (e.g., Goldstein et al. [6]). To impose the no-slip and no-penetration boundary conditions at the interface, F is modeled as... 

The use of the forcing term only in points that define the contour of the submerged body permits fluid to move within the body. When calculating the velocity gradient in the direction normal to the wall by the finite difference method, errors in the prediction of derivative may surge. To solve this problem, the forcing term can be applied to all points within the immersed body in addition to its border points. 

As it was mentioned before, immersed boundary method is used in the paper [6]. This method is based on the fact, that in case of flowing over a body the fluid is effected by surface force and shear force if the body has no-slip boundary condition. The body surface is influenced by the same forces of opposite sign. It means that fluid flowing over the body can be modeled by a corresponding held of the external body forces [20]. 

A solid surface interacts with its surrounding molecules (in the gas or liquid phase) in varying degrees. For example, if a solid is immersed in a liquid, the interaction between the two bodies will be of interest. The interaction of a substance with a solid surface can be studied by measuring the heat of adsorption (besides other methods). The information one needs is whether the process is exothermic (heat is produced) or endothermic (heat is absorbed). This leads to the understanding of the mechanism of adsorption and helps in the application and design of the system. Calorimetric measurements have provided much useful information. When a solid is immersed in a liquid (Figure 5.10), in most cases there is a liberation of heat ... 

Several methods are available to evaluate a patient s actual body composition rather than total body mass. Skin-fold measurement may be of value in evaluating subcutaneous adiposity (adipose tissue accumulation) proper technique is required for reliable results. Other anthropomorphic measurements such as bioelectrical impedance, dual-energy x-ray absorptiometry, and total body water immersion are also available.These last techniques are often of value in research studies, but it is clinically impractical to use them routinely (Elberg et al., 2004). 

If a hot steel ball were immersed in a cool pan of water, the lumped-heat-capacity method of analysis might be used if we could justify an assumption of uniform ball temperature during the cooling process. Clearly, the temperature distribution in the ball would depend on the thermal conductivity of the ball material and the heat-transfer conditions from the surface of the ball to the surrounding fluid, i.e., the surface-convection heat-transfer coefficient. We should obtain a reasonably uniform temperature distribution in the ball if the resistance to heat transfer by conduction were small compared with the convection resistance at the surface, so that the major temperature gradient would occur through the fluid layer at the surface. The lumped-heat-capacity analysis, then, is one which assumes that the internal resistance of the body is negligible in comparison with the external resistance. 

The Bernoulli theorem may be used to determine the change in pressure caused by retardation of fluid at the upstream side of a body immersed in a fluid stream. This principle is applied in the Pitot tube, shown in Fig. 1C. The fluid velocity is reduced from Ma. the velocity of the fluid filament in alignment with the tube, to zero at B, an position known as the stagnation point. The pressure, P, is measured at this point by the method shown in Fig.l C. The undisturbed pressure, P, is measured in this example with a tapping point in the wall connected to a manometer. 

Use of 3D foams is also a popular method for bone regeneration applications, although they are most often employed for trabecular bone regeneration [152,154]. There are a few methods utilized to create foams for this application, one of the most popular being a polymer foam replication technique, in which a polymer foam is either electrosprayed or immersed into a HAp/bioactive glass particle slurry in order to fully coat the foam and create a trabecular bone-like aichitecture. However, other methods are also utilized, including creating composite foam solutions that are injectable and form once inside the body [153]. Results of Fu et al. [152] have indicated mechanical properties similar to those of natural trabecular bone. 

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