For the porosities
of [beta] = 0.4, 0.5, 0.6 and 0.7, in contrast to the bare cylinder case, there is no a distinct concentration in the Reynolds shear stress contours.
Numbers and 1 single sphere 2 spheres, 2 spheres, distribution random vertical Young's modulus 37,059 36,819 38,112 (MPa) Error 1% 3% Numbers and 8 spheres, 8 spheres, 9 spheres distribution vertical horizontal Young's modulus 38,830 37,825 37,011 (MPa) Error 5% 2% 0% Numbers and 2 spheres, 4 spheres, 4 spheres, star distribution horizontal square Young's modulus 35,718 37,969 37,115 (MPa) Error 4% 2% 0% Numbers and 10 spheres, 10 spheres, 10 spheres, varied distribution horizontal vertical sizes Young's modulus 38,017 37,825 36,820 (MPa) Error 3% 2% 1% Table 5: Results for simulating different porosities
under fully dry situation.
Mass Transfer Properties under Different Initial Porosities
. As shown in Figure 9, the mass transfer decreases with the decrease of initial porosity.
ranging from 10% to 60% as aforementioned are introduced into the cubes in the form of uniformly spaced disconnected spherical holes conforming to the square array pore distribution pattern as illustrated in Figure 1.
However, at low porosities
, the pores are close to being spherical due to the surface energetics of melting and resolidification.
Adding, multiplying, or dividing the natural logarithm affects the upper and lower ends of the initial values of effective porosity and can shift the ranges of porosities
up or down.
Despite the fact that clays have very high porosities
, the permeability is very low (about [10.sup.-10] - [10.sup.-11]).
These depth relationships are important because soil layers with high bulk densities and low porosities
can restrict water movement and inhibit root extension.
But the error in determining rock capacity factor for samples with low sorption capacities or porosities
([alpha] close to zero) may be significant, resulting again in large errors in [D.sub.a], (Grathwohl, 1998).
For the studied range of porosities
and a suggested thermal conductivity of quartz, neither the arithmetic, Maxwell, nor the harmonic model can satisfactorily explain the observed thermal conductivity-porosity relationship in our data set (Fig.
Using ProCAST, the tooling engineer identified large shrink porosities
in the casting.
Silica gels used for thermal insulation typically have porosities
of 95 to 99 percent, he says.