Radial thermal displacement

The vibration amplitudes of the framework atoms appear to be quite normal (Table V). The average for the r.m.s. radial thermal displacement of the T and O atoms is 0.127 and 0.213 A, respectively. Judged from the vibration ellipsoids of the T atoms, the framework appears to exhibit some anisotropic vibrations. Details of the interpretation of the anisotropic temperature coefficients will be discussed in a separate paper. 

However, for the conducting Cu sample, simulation results indicate that the temperature is usually lower than that of AI2O3 case, whereas the temperature difference inside the sample at steady state is higher for Cu than for AI2O3. Figure 6.28 shows the radial mechanical displacement distribution at steady state, as the system is applied with a current of 1000 A and a pressure of 140 MPa for the case of alumina and copper sample. The corresponding radial and axial components of the stress distribution field, due to thermal and Poisson-type expansion, are illustrated in Fig. 6.29, for the AI2O3 (a and c) and Cu (b and d) samples [41]. 

Displacements measured by MPBXs constitute the bulk of the mechanical measurements in the DST. The DCS continuously scanned the displacement sensors and recorded the readings at a frequency of four per 24 hours. Figure 7 shows the measured displacement histories in one of the 12 radial holes drilled from inside the HD. Hole 155 is inclined up at 30 degrees to the vertical in a transverse plane at y = 21m. Millard and Rutqvist, 2003 and Hsiung et al, 2003 discuss the thermal-... 

To get better the understanding of the system, the mechanical behaviour of the clay has been taken into account. The initial conditions are null total stresses everywhere. So, in-situ mechanical stresses are not taken into account. The results of our THM calculation show only stresses induced by thermal-hydro-mechanical couplings. The contact between the EB and the canister is once again supposed to be perfect, so that no radial displacement of the clay is allowed at that boundary. Biot s poroelastic model is chosen to represent clay behaviour. It takes partial saturation into account via an equivalent pressure which includes capillary effects, involving both gas and liquid, Dangla (1998). Biot s model is added as fourth equation to the system. The associated main variable is total stress state. The couplings with thermal-hydraulics behaviour are introduced by... 

The role of mechanics on liquid darcean flux does not depend on the mechanical boundary condition the saturation time is 5 years 11 months and 26 days, like in the thermal-hydro-mechanical reference calculation. The nnaximal radial displacement is observed, when the saturation is achieved, at the contact EB-site there the EB expands. The site is contracted in response. The maximal values for EB extension are available on table 6. It reveals that the boundary condition at the interface EB-canister only has a very weak effect on the EB-site interface behaviour, 80 cm away. Like gas boundary condition, mechanical boundary condition does not disturb the saturation phenomenon, whose kinetics remains dominated by darcean water flux. 

Fig. 112 shows the temperature profile for the moment at which the dynamic equilibrium is established, when steam is injected into the bed without interruption at rates indicated above. We may accept 70°C to be the minimum temperature at which petroleum can still be actively displaced from the reservoir by the heat carrier. In that case, the maximum radial distance from the injection well at which steam still has some effect is about 180 m (Fig. 112). At that point, the thermal efficiency co-efficient does not exceed 0.15.

In the plunger-die-sample region, the radial displacement increases relatively uniformly with increasing radius, and thus, the highest displacement is observed near the surface of the die. These radial displacements are due to the synergistic effect of the thermal expansion and a Poisson-type expansion due to the pressure applied in the vertical direction. In contrast, the radial distribution, in the case of the Cu sample (Fig. 6.29b), does not increase uniformly with the radial position. Instead, the portion where the copper is in contact with the die wall has larger... 

A slot end-milling test is carried out to investigate the machine tool spindle error motion in radial direction. Table 29.3 shows the tool and cutting conditions. The cutting time for one operation should be short enough to avoid the thermal disturbances on displacement signals. 

This assumes that the power density R and the thermal conductivity k are uniform and the temperature at r = ft is taken as the reference zero. For solid cylinders the logarithmic term becomes zero and the distribution is parabolic. When such a temperature distribution is imposed on a finite cylinder it distorts so that the flat end faces bulge out and the curved surface bends outwards, the rim being displaced further than the center belt. An exaggeration of this shape is shown in Fig. 2 for sections of a solid cylinder and a hollow cylinder where a jb = 0.2. In this case most of the rim displacement takes place within 0.1 of the cylinder length from the end. For a cylinder with a length to diameter ratio of 1 the difference between the radial displacements of the rim and belt is approximately half... 

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