水的粘度计算表
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水的黏度表(0～40℃)
温度T 粘度μ Pa·s或N·s·m-2
温度 T 粘度μ
Pa·s或N·s·m-2 ℃ K ℃ K
0 ×10-3 ×10-3
1 ×10-3 21 ×10-3
2 ×10-3 22 ×10-3
3 ×10-3 23 ×10-3
4 ×10-3 24 ×10-3
5 ×10-3 25 ×10-3
6 ×10-3 26 ×10-3
7 ×10-3 27 ×10-3
8 ×10-3 28 ×10-3
9 ×10-3 29 ×10-3
10 ×10-3 30 ×10-3
11 ×10-3 31 ×10-3
12 ×10-3 32 ×10-3 13 ×10-3 33 ×10-3
14 ×10-3 34 ×10-3
15 ×10-3 35 ×10-3
16 ×10-3 36 ×10-3
17 ×10-3 37 ×10-3
18 ×10-3 38 ×10-3
19 ×10-3 39 ×10-3
20 ×10-3 40 ×10-3
水的物理性质
温度t/℃ 饱和蒸气压
p/kPa 密度ρ/kg·m-3 焓
H/kJ·kg-1 比定压热容cp/kJ·kg-1·K-1 导热系数λ/10-2W·m-1·K-1 粘度μ/10-5Pa·s 体积膨胀系数α/10-4K-1 表面张力σ/10-3N·m-1 普兰德数Pr
0 0
10
20
30
40 50
60
70
80
90
100
110
120
130
140
150
160
170
180
190
200
210 F3??? Viscosity decreases with pressure 220
230
240
250
260
270
280
290
300
310
320
330
340
350
360 109
370 264 (at temperatures below 33°C)
Viscous flow occurs by molecules moving through the voids that exist between them. As
the pressure increases, the volume decreases and the volume of these voids reduces, so
normally increasing pressure increases the viscosity.
Water's pressure-viscosity behavior [] can be explained by the increased pressure (up to
about 150 MPa) causing deformation, so reducing the strength of the hydrogen-bonded
network, which is also partially responsible for the viscosity. This reduction in cohesivity
more than compensates for the reduced void volume. It is thus a direct consequence of the
between hydrogen bonding effects and the van der Waals dispersion forces [] in water;
hydrogen bonding prevailing at lower temperatures and pressures. At higher pressures (and
densities), the between hydrogen bonding effects and the van der Waals dispersion forces
is tipped in favor of the dispersion forces and the remaining are stronger due to the
closer proximity of the contributing oxygen atoms []. Viscosity, then, increases with
pressure. The dashed line (opposite) indicates the viscosity minima. The variation of viscosity with pressure and temperature has been used as evidence that
the viscosity is determined more by the extent of hydrogen bonding rather than hydrogen
bonding strength.
Self-diffusion is also affected by pressure where (at low temperatures) both the
translational and rotational motion of water anomalously increase as the pressure
increases.
