189:
The local physical velocity can still be different than the average fluid velocity because the vector of the local fluid flow does not have to be parallel to that of average flow. Also, there may be local constriction in the flow channel.
42:
Superficial velocity is used in many engineering equations because it is the value which is usually readily known and unambiguous, whereas real velocity is often variable from place to place.
39:
or fluid were the only one flowing or present in a given cross sectional area. Other phases, particles, the skeleton of the porous medium, etc. present in the channel are disregarded.
86:
154:
180:
51:
123:
219:
165:
8:
117:
velocity and the superficial velocity can be expressed as (for one-dimensional flow):
214:
199:
24:
185:
u is the average fluid velocity (excluding the other phase, solids, etc.), m/s.
36:
208:
32:
28:
114:
110:
168:
126:
54:
174:
148:
80:
206:
99:- superficial velocity of a given phase, m/s
45:Superficial velocity can be expressed as:
207:
102:Q - volume flow rate of the phase, m/s
81:{\displaystyle u_{s}={\frac {Q}{A}}}
13:
14:
231:
31:, is a hypothetical (artificial)
1:
113:, the dependence between the
149:{\displaystyle u_{s}=\phi u}
7:
193:
105:A - cross sectional area, m
35:calculated as if the given
10:
236:
182:is porosity, dimensionless
21:superficial flow velocity
176:
150:
82:
177:
175:{\displaystyle \phi }
151:
109:Using the concept of
83:
23:), in engineering of
166:
124:
52:
17:Superficial velocity
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146:
78:
76:
227:
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155:
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25:multiphase flows
235:
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200:Volumetric flux
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220:Fluid dynamics
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33:flow velocity
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27:and flows in
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22:
18:
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108:
90:
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29:porous media
20:
16:
15:
209:Categories
170:ϕ
141:ϕ
115:advection
215:Velocity
194:See also
111:porosity
159:where:
91:where:
37:phase
19:(or
211::
144:u
138:=
133:s
129:u
97:s
95:u
74:A
71:Q
66:=
61:s
57:u
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