Coefficient of normal restitution of viscous particles and cooling rate of granular gases
نویسندگان
چکیده
We investigate the cooling rate of a gas of inelastically interacting particles. When we assume velocity dependent coefficients of restitution the material cools down slower than with constant restitution. This behavior might have large influence to clustering and structure formation processes. PACS numbers: 83.70.Fn, 62.40.+i, 81.40.Lm, 05.40. -y, 46.10 +z Typeset using REVTEX 1 The behavior of granular gases has been of large scientific interest in recent time. Goldhirsch and Zanetti [1] and McNamara and Young [2] have shown that a homogeneous granular gas is unstable. After some time one observes dense regions (clusters) and voids. To evaluate the loss of mechanical energy due to collisions one introduces the coefficient of (normal) restitution g′ = ǫg , (1) where g = |~g| and g = ∣
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