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Gruneisen coefficient

Specific heat and Gruneisen coefficient. The temperature behind a shock can be written as... [Pg.321]

In order to characterize the state of a material following constant volume heating, the pressure-energy coupling relationship must be known. The relationship is determined through the Gruneisen coefficient, T, of the material, as it appears in the Mie-Gruneisen equation of state [51], and can be written in... [Pg.285]

An effective Gruneisen coefficient can be defined for solid materials, including substances such as granular explosives, by... [Pg.286]

The effective P may be determined with the electron beam apparatus. When the sample (slab geometry) is thick enough to absorb all of the incident electrons, a compressive stress wave propagates from the irradiated region into the sample bulk. A transducer, located just beyond the deposition depth, may be used to record the stress pulse. Alternatively, the displacement or velocity of the rear surface of sample may be observed optically and used to infer the initial pressure distribution from the experimentally measured stress history. Knowledge of the energy-deposition profile then permits the determination of the Gruneisen coefficient. [Pg.286]

It is possible to compute a mean Gruneisen coefficient, F, for lead azide by using an effective bulk modulus, (defined by the ratio of the applied pressure to the relative volume change), and the volume expansion coefficient, a, as... [Pg.287]

According to the generally accepted relations that connect detonation velocity at one side and the explosive density and the heat of detonation at another, the Gruneisen coefficient depends only on the volume. By integrating Eq. (5.60), the Gruneisen equation of state is obtained ... [Pg.197]

The expansion coefficient of a solid can be estimated with the aid of an approximate thermodynamic equation of state for solids which equates the thermal expansion coefficient (5 with the quantity yC p/B where y is the Gruneisen dimensionless ratio, C is the specific heat of the solid, p is the density of the material, and B is the bulk modulus. For fee metals the average value of the Gruneisen constant is near 2.3. However, there is a tendency for this constant to increase with atomic number. [Pg.950]

Gruneisen parameter (y) - Defined by y = u /k Cy p, where is the cubic thermal expansion coefficient, k is the isothermal compressibility, c, is the specific heat capacity at constant volume, and p is the mass density, y is independent of temperature for most crystalline solids. [1]... [Pg.105]

There are some physical generalities concerning thermal expansion coefficients. One empirical correlation is that is constant for a wide range of cubic and close-packed compounds, where T is the melting point and is the volume coefficient of thermal expansion. The Griineisen equation relates ol to the compressibility Kq, the heat capacity c , and the molar volume V here y is the Gruneisen constant, a proportionality constant of first order ... [Pg.159]

TABLE 47 Ideal (X-ray) density (p), Gruneisen parameter (yy), isohoric heat capacity (Cy, Z = 4), entropy (S), bulk Kj) and shear (G ) moduli, and volumetric thermal expansion coefficient (ay) calculated for RGaOj (R = La-Gd) at 300 K using semi-classical approach (Senyshyn et al., 2005b]... [Pg.280]

Gruneisen s Law. relates thermal conductivity y, linear thermal expansion coefficient a, compressibility K and specific heat C, for a solid of volume V, by 3aV = yKC. ... [Pg.148]

Compound Sommerfeld coefficient Bulk modulus Electronic Gruneisen parameter ... [Pg.397]

Fig. 29. GrUneisen analysis for CeAl3 showing the measured coefficients of specific heat (upper plot), thermal expansion (middle plot) and the Griineisen parameter deduced from their ratio (lower plot). As the temperature is lowered Q approaches saturation to a value 50. Below 1 K it Crosses over to a large negative value (-200) appropriate to the ground state. Data for C(T) from Phillips et al. (1987) for p from Andres et al. (1975) and from Ribault et al. (1979). Fig. 29. GrUneisen analysis for CeAl3 showing the measured coefficients of specific heat (upper plot), thermal expansion (middle plot) and the Griineisen parameter deduced from their ratio (lower plot). As the temperature is lowered Q approaches saturation to a value 50. Below 1 K it Crosses over to a large negative value (-200) appropriate to the ground state. Data for C(T) from Phillips et al. (1987) for p from Andres et al. (1975) and from Ribault et al. (1979).
Several uranium compounds with Sommerfeld coefficients in the range y = 90-150mJ/ mol have had both thermal expansion and specific heat measured. Results for UAI2 are shown in fig. 31. The Gruneisen parameter increases with temperature in a similar way as in UPt3, except that the limiting value at T = 0 (f3= 18) is smaller. Indeed, this value is comparable to the value of Q in mixed-valent compounds with similar values of y. At higher temperatures approaches values characteristic of phonons. [Pg.435]

Fig. 31. Griineisen analysis for the spin-fluctuation compound UAl, The upper plots show the measured coefficients of thermal expansion and specific heat C T. The lower plot shows the temperature-dependent Gruneisen parameter deduced using eq. (1). Data for Cp from Frings (1984) for from de Visser (1986). Fig. 31. Griineisen analysis for the spin-fluctuation compound UAl, The upper plots show the measured coefficients of thermal expansion and specific heat C T. The lower plot shows the temperature-dependent Gruneisen parameter deduced using eq. (1). Data for Cp from Frings (1984) for from de Visser (1986).
As the isothermal compressibility Xt the specific heat capacity at constant volume are both values which are always positive, the Gruneisen parameter has the same sign as the expansion coefficient - i.e. positive in the majority of cases and negative in the few cases of contraction with increased temperature. [Pg.65]

Experimentally, the Gruneisen parameter is determined at zero pressure or atmospheric pressme, on the basis of measurements of the voliune expansion coefficient p, the adiabatic compressibility... [Pg.66]


See other pages where Gruneisen coefficient is mentioned: [Pg.173]    [Pg.290]    [Pg.12]    [Pg.287]    [Pg.506]    [Pg.131]    [Pg.51]    [Pg.388]    [Pg.173]    [Pg.290]    [Pg.12]    [Pg.287]    [Pg.506]    [Pg.131]    [Pg.51]    [Pg.388]    [Pg.158]    [Pg.188]    [Pg.417]    [Pg.321]    [Pg.766]    [Pg.54]    [Pg.26]    [Pg.296]    [Pg.393]    [Pg.395]    [Pg.401]    [Pg.405]    [Pg.406]    [Pg.406]    [Pg.426]    [Pg.441]    [Pg.447]    [Pg.60]    [Pg.115]    [Pg.878]   
See also in sourсe #XX -- [ Pg.285 , Pg.286 , Pg.287 ]

See also in sourсe #XX -- [ Pg.197 ]




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