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<br />. <br /> <br />36 <br /> <br />is the boundary Reynolds number, <br /> <br />D is the size of sediment, <br />s <br /> <br />U. is the <br /> <br />shear velocity (D. = 1T7P), and v is the kinemetic viscosity of the fluid. <br />o <br /> <br />. <br /> <br />2.5.3.2 The Einstein Method for Suspended Sediment Load Estimation <br /> <br />This method relies upon an integration of the sediment concentration pro- <br /> <br />. <br /> <br />file as a function of depth. The nature of the profi le is determined using <br /> <br />turbulent transport theory. The sediment profile is assured to be in equi- <br /> <br />librium and therefore, the rate at which sediment is transported upward due <br /> <br />. <br /> <br />to turbulence and the concentration gradient are exactly equal to the rate <br /> <br />at which gravity is transporting sediment downward. If the sediment concen- <br /> <br />tration is known at one point, then the entire concentration is determined. <br /> <br />. <br /> <br />The point of known concentration is assumed to be the upper limit of the <br /> <br />bed-load layer. The resulting equation is <br /> <br />qs <br /> <br />qb <br />11.6 <br /> <br />w-l <br />K <br />.(1 - K) w <br /> <br />v <br />[( - + 2.5) II + 2.5 12 ] <br />U. <br /> <br />(2 -13) <br /> <br />. <br /> <br />in which, qs = the suspended load, <br /> <br />qb <br /> <br />the bed load determined by using Equation 2-10 or other <br />appropriate bed-load equations, <br /> <br />. <br /> <br />K = the relative depth of the bed layer, <br />U. = the shear velocity, <br />V = the mean ve 10city of flow, <br />11 and 12 = Einstein integrals, and <br />w = a dimensionless parameter given by <br /> V <br /> s <br />w = <br /> KD. <br /> <br />. <br /> <br />. <br /> <br />(2-14) <br /> <br />In Equation 2-14, <br /> <br />V = the fall velocity of the sediment particle, and <br />s <br />K = the Karman constant (usually 0.4 is used). <br /> <br />. <br /> <br />. <br />