[0009] 为了解决上述问题,本发明提供了一种斜流泵叶轮水力设计方法。通过改善叶轮的几个重要参数的设计方法,改善流动情况,提高斜流泵水力效率和稳定性能。
[0010] 实现上述目的所采用的技术方案是:
[0011] (1)叶轮出口直径D2
[0012]
[0013] 式中:
[0014] Q-设计工况的流量,米3/秒;
[0015] D2-叶轮出口直径,米;
[0016] D20-叶轮最小出口直径,米;
[0017] D2h-叶轮最大出口直径,米;
[0018] n-设计工况的转速,转/分;
[0019] MD2-叶轮出口直径系数;
[0020] (2)叶片出口宽度b2
[0021] b2=Mb2.[0.0984Q0.3345-0.9473n0.00904+1.01] (2)
[0022] 式中:
[0023] Q-设计工况的流量,米3/秒;
[0024] b2-叶片出口宽度,米;
[0025] n-设计工况的转速,转/分;
[0026] Mb2-叶片出口宽度系数;
[0027] (3)叶轮进口当量直径D0
[0028]
[0029] 式中:
[0030] Q-设计工况的流量,米3/秒;
[0031] n-设计工况的转速,转/分;
[0032] MD0-叶轮进口当量直径系数;
[0033] (4)叶轮出口直径系数MD2
[0034]
[0035] 式中:
[0036] ns-比转数;
[0037] (5)叶片出口宽度直径系数Mb2
[0038]
[0039] 式中:
[0040] ns-比转数;
[0041] (6)叶轮进口当量直径系数MD0
[0042]
[0043] 式中:
[0044] ns-比转数;
[0045] Q-设计工况的流量,米3/秒;
[0046] H-设计工况扬程,米;
[0047] (7)斜流泵叶轮出口与水平夹角α
[0048]
[0049] 式中:
[0050] α-斜流泵叶轮出口与水平夹角,度;
[0051] D2-叶轮出口直径,米;
[0052] b2-叶片出口宽度,米;
[0053] n-设计工况的转速,转/分;
[0054] ns-比转数;
[0055] H-设计工况扬程,米;
[0056] g-重力加速度,米/秒2;
[0057] (8)叶轮前盖板进口圆角半径系数MRDB
[0058] MRDB=0.0905ln(ns)-0.1836 (8)
[0059] 式中:
[0060] MRDB-叶轮前盖板进口圆角半径系数;
[0061] ns-比转数;
[0062] (9)叶轮前盖板进口圆角半径RDB
[0063] RDB=MRDB·(0.3853Q0.3335-2.9056n0.01142+3.1508) (9)
[0064] 式中:
[0065] RDB-叶轮前盖板进口圆角半径,米;
[0066] Q-设计工况的流量,米3/秒;
[0067] MRDB-叶轮前盖板进口圆角半径系数;
[0068] (10)叶轮圆螺母半径Ra、叶轮圆螺母高度Rb
[0069] Ra=16.5311n(D0)-65.11 (10)
[0070] Rb=1.51Ra (11)
[0071] 式中:
[0072] Ra-叶轮圆螺母半径,米;
[0073] D0-叶轮的进口当量直径,米;
[0074] Rb-叶轮圆螺母高度,米;
[0075] (11)叶轮后盖板进口圆角半径系数MRTS
[0076]
[0077] 式中:
[0078] MRTS-叶轮后盖板进口圆角半径系数;
[0079] na-比转数;
[0080] (12)叶轮后盖板进口圆角半径RTS
[0081]
[0082] 式中:
[0083] RTS-叶轮后盖板进口圆角半径,米;
[0084] RDB-叶轮前盖板进口圆角半径,米;
[0085] D0-叶轮进口当量直径,米;
[0086] b2-叶片出口宽度,米;
[0087] MRTS-叶轮前盖板进口圆角半径系数;
[0088] Ra-叶轮圆螺母半径,米;
[0089] (13)叶轮前盖板叶片进口处与前盖板出口的距离ZE
[0090]
[0091] 式中:
[0092] ZE-叶轮前盖板叶片进口处与前盖板出口的距离,米;
[0093] n-设计工况的转速,转/分;
[0094] ns-比转数;
[0095] H-设计工况扬程,米;
[0096] g-重力加速度,米/秒2;
[0097] (14)进口边距前盖板曲线开始端距离g1
[0098]
[0099] 式中:
[0100] g1-进口边距前盖板曲线开始端距离,米;
[0101] RDB-叶轮前盖板进口圆角半径,米;
[0102] MRDB-叶轮前盖板进口圆角半径系数;
[0103] (15)叶片进口轴面速度vm1
[0104]
[0105] 式中:
[0106] ns-比转数;
[0107] H-设计工况扬程,米;
[0108] g-重力加速度,米/秒2;
[0109] (16)叶片出口轴面速度vm2
[0110]
[0111] 式中:
[0112] ns-比转数;
[0113] H-设计工况扬程,米;
[0114] (17)叶片出口圆周速度u2
[0115]
[0116] 式中:
[0117] ns-比转数;
[0118] H-设计工况扬程,米;
[0119] g-重力加速度,米/秒2;
[0120] (18)水力效率ηh
[0121] ηh=1+0.0835lg(0.09633Q0.3335-0.7264n0.01142+0.7877) (19)
[0122] 式中:
[0123] Q-设计工况的流量,米3/秒;
[0124] n-设计工况的转速,转/分;
[0125] (19)滑移系数ρ
[0126]
[0127] 式中:
[0128] H-设计工况扬程,米;
[0129] vm2-叶片出口轴面速度,米/秒;
[0130] u2-叶片出口圆周速度,米/秒;
[0131] ηh-水力效率;
[0132] (20)叶片进口安放角β1
[0133]
[0134] 式中:
[0135] ns-比转数;
[0136] Dj-叶轮进口直径,米;
[0137] vm1-叶片进口轴面速度,米/秒;
[0138] n-设计工况的转速,转/分;
[0139] (21)叶片出口安放角β2
[0140]
[0141] 式中:
[0142] ns-比转数;
[0143] vm2-叶片出口轴面速度,米/秒;
[0144] ρ-滑移系数;
[0145] u2-叶片出口圆周速度,米/秒;
[0146] ηh-水力效率;
[0147] g-重力加速度,米/秒2;
[0148] (22)叶片安放角β
[0149]
[0150] 式中:
[0151] β-叶片安放角,度;
[0152] β1-叶片进口安放角,度;
[0153] β2-叶片出口安放角,度;
[0154] ns-比转数;
[0155] (23)叶轮叶片数z
[0156]
[0157] 式中:
[0158] D2-叶轮出口直径,米;
[0159] z-叶轮叶片数;
[0160] β1-叶片进口安放角,度;
[0161] β2-叶片出口安放角,度;
[0162] Dj-叶轮进口直径, 其中dh为轮毂直径;当dh=0时;
[0163] (24)叶片包角
[0164]
[0165] 式中:
[0166] ns-比转数;
[0167] z-叶轮叶片数;
[0168] (25)叶片名义厚度修正值δk
[0169]
[0170] 式中:
[0171] ns-比转数;
[0172] H-设计工况扬程,米;
[0173] D2-叶轮出口直径,米;
[0174] z-叶轮叶片数;
[0175] (26)叶片每点真实厚度δ
[0176] δ=Mδ·δk (27)
[0177] Mδ=0.7368e(0.0031L) (28)
[0178] 式中:
[0179] δ-叶片每点真实厚度,米;
[0180] Mδ-叶片厚度系数;
[0181] δk-叶片名义厚度修正值,米;
[0182] L-叶片长度,米;
[0183] 根据上述步骤,可以得到一种相对系统的、精确的叶轮主要参数的设计方法。
[0184] 通过上述计算方法确定斜流泵叶轮主要几何参数,包括叶轮出口直径、叶轮进口当量直径、叶片出口宽度、斜流泵叶轮出口与水平线夹角、叶轮前盖板进口圆角半径、叶轮圆螺母半径、叶轮圆螺母高度、叶轮后盖板进口圆角半径、叶轮前盖板叶片进口处与前盖板出口的距离、进口边距前盖板曲线开始端距离、叶片进口轴面速度、叶片出口轴面速度、叶片出口圆周速度、水力效率、滑移系数、叶片进口安放角、叶片出口安放角、叶片安放角、叶轮叶片数、叶片包角、叶片每点真实厚度,不同于传统相似法与速度系数法,更能确保水力部件尺寸的相互匹配,计算更精确,使理论设计与实际模型更符合,而且更有利于计算机的应用与编程。