user's manual for corhyd: an internal diffuser hydraulics model - IfH

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feeder velocity is mentioned, if a feeder is applied. On the second axis of this graph the diffuser diameter variation along the diffuser is shown. Fig. 21: Graphical output: bar charts showing the discharge per riser, the relative discharge deviation and port/riser headloss distribution, the discharge velocity at ports, the velocity in the diffuser pipe as well as port and diffuser diameter. The second output (Fig. 22) describes the hydraulic and energy grade line (in fresh water heights) of the whole system. It indicates locations of major losses and shows the needed total head to drive the system (headworks head) as well as the total losses. Institut für Hydromechanik, Universität Karlsruhe 45
Fig. 22: Graphical output: Energy and Hydraulic grade line of the whole system and the diffuser Graphical output for T-Diffuser: In progress 6 Design and optimization The governing equation for the individual port discharge is equation (20). Equation (18) in (20) devided by q i and squared gives: i ⎛ ⎞ ⎜∑ q k ⎟ 2 = ( ) ( ) ⎝ k 1 ⎠ p d,i − p a,i + 2g z d,i − z jet,i + 2 ρ e A d,i 1 = (24) 2 2 2 2 n p,i n ⎛ ⎞ ⎛ λ ⎞ r ,i q α ⎛ ⎞ ⎛ λ ⎞ i i ∑⎜ q α p,i, jL i i p,i, j r,i, j r,i, j + ⎟ ⎜ζ + ⎟ + ∑⎜ q L i ⎟ ⎜ζ + ⎟ 2 ( ) p,i, j r,i, j C A j= 1 ⎝ A p,i, j ⎠ ⎝ D p,i, j ⎠ j= 1 ⎝ A r,i, j ⎠ ⎝ D r,i, j ⎠ c,i p,i where the losses along the diffuser are included in the internal pressure p d,i from equation (18). The first two terms in the numerator denote the difference of the piezometric head (hydraulic 2 head) ( p d,i − p a,i ) + 2g( z d,i − z jet, i ) = ∆ i between the diffuser and the ambient. The third term ρ e in the numerator is related to the diffuser velocities v d,i . The terms in the denominator are related to the jet velocity v j , i = α i q i /(C c A p,i ) and the port and riser losses. For outfalls with uniform geometries or for uniform diffuser sections with uniform port/riser groups it follows A i = A = const., α i = α = const., D i = D = const., L i = L = const.. Assuming a uniform flow distribution among the orifices gives v r,i = v r and v p,i = v p = const.. Therefore all losses but the riser inlet loss and the port exit loss are constant (λ i = λ = const., ζ p,i = ζ p ). Under these assumptions only few parameters change along the diffuser causing the variation of individual flows. The other parameters can be joint in constants C i : 1 = ∆ i + v d,i ² C 1 /C c,i 2 + C 2 ζ dr,i (25) For diffuser without risers it is: Institut für Hydromechanik, Universität Karlsruhe 46 2
Page 1 and 2: Universität Karlsruhe Institut fü
Page 3 and 4: Acknowledgments The authors like to
Page 5 and 6: 10.1 Local loss formulations: Divis
Page 7 and 8: 1 Introduction CorHyd is a computer
Page 9 and 10: Fig. 1: Outfall configuration showi
Page 11 and 12: where j 0 denotes the buoyancy flux
Page 13 and 14: 2.4 Manifold processes Pipe hydraul
Page 15 and 16: Fig. 8: Local port/riser branch los
Page 17 and 18: Table 2: Local loss formulations Ty
Page 19 and 20: Gradual contraction (Idelchik 1986)
Page 21 and 22: Where H denotes the headloss, V duc
Page 23 and 24: Table 3: Equivalent sand roughness
Page 25 and 26: Institut für Hydromechanik, Univer
Page 27 and 28: For a constant sea water level and
Page 29 and 30: (16) solved for r in (15) and assum
Page 31 and 32: 3.1.4 Automatic implementation of l
Page 33 and 34: elevation difference between diffus
Page 35 and 36: The iteration stops if the differen
Page 37 and 38: Table 4: CorHyd subroutines and the
Page 39 and 40: 4 Data Input Input can either be do
Page 41 and 42: (ρ 0,max > ρ 0 ). Further sensiti
Page 43 and 44: should allow for riser velocities,
Page 45 and 46: Fig. 19: First input sub-window for
Page 47: 10 7050.000 0.000 -2.500 11 7000.00
Page 51 and 52: given dilution requirements and maj
Page 53 and 54: 6.3 Off design conditions It was co
Page 55 and 56: Table 5: Sensitivity of involved pa
Page 57 and 58: Fig. 24: Side view and cross sectio
Page 59 and 60: Fig. 27: Flow characteristics for d
Page 61 and 62: under different flow conditions. Th
Page 63 and 64: Fig. 32: Side view and cross sectio
Page 65 and 66: Fig. 34: Flow characteristics for:
Page 71 and 72: Table 6: Comparison of construction
Page 73 and 74: seaward end, which can be prevented
Page 75 and 76: Especially for this long diffuser a
Page 77 and 78: Jirka, G.H., Doneker, R.L. and Hint
Page 79 and 80: 10 Annex 10.1 Local loss formulatio

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