9. Physical Modeling
307
in a closed pipe where turbulence is fully developed so that viscous forces
are negligible and gravity force and surface tension force is absent.
Eu =
V
y/\p/p)
where V is the average velocity, p is the pressure intensity and p is the
density of the fluid.
Weber’s model law
The Weber number dénotés the ratio of the inertial forces to surface tension
forces. The Weber number becomes an important parameter when dealing
with applications involve two fluid interfaces such as the flow of thin films
of liquid and bubble formation. Weber model law is the law in which models are based on Weber’s number and dynamic similarity between model
and prototype can be achieved when the Weber number for both model
and prototype are equal. This law is applicable for capillary rise and fall
problems.
We = pV2L/(j
Where cr dénotés surface tension
Mach’s model law
Mach’s number is defined as the square root of the ratio of the inertia force
of a flowing fluid to the elastic force. Mach model law is the law in which
models are designed on Mach number, which is the ratio of the square root
of inertia force to elastic force of a fluid. Hence where the forces due to
elastic compression are prominent in addition to inertia force, the dynamic
similarity between the model and its prototype is obtained by equating the
Mach number of the model and its prototype.
Ma = V/c
where c is the speed of sound (343 m/s at 20°C) and V is the fluid velocity.
9.7 Case Studies
Physical model studies are widely used in the field of coastal engineering
to assess the stability and performance of structures. Typically to initiate
a model study, the scaling law to be followed is decided first. Figure 9.2
projects the prototype and model scale down version of a flaring shaped
307
in a closed pipe where turbulence is fully developed so that viscous forces
are negligible and gravity force and surface tension force is absent.
Eu =
V
y/\p/p)
where V is the average velocity, p is the pressure intensity and p is the
density of the fluid.
Weber’s model law
The Weber number dénotés the ratio of the inertial forces to surface tension
forces. The Weber number becomes an important parameter when dealing
with applications involve two fluid interfaces such as the flow of thin films
of liquid and bubble formation. Weber model law is the law in which models are based on Weber’s number and dynamic similarity between model
and prototype can be achieved when the Weber number for both model
and prototype are equal. This law is applicable for capillary rise and fall
problems.
We = pV2L/(j
Where cr dénotés surface tension
Mach’s model law
Mach’s number is defined as the square root of the ratio of the inertia force
of a flowing fluid to the elastic force. Mach model law is the law in which
models are designed on Mach number, which is the ratio of the square root
of inertia force to elastic force of a fluid. Hence where the forces due to
elastic compression are prominent in addition to inertia force, the dynamic
similarity between the model and its prototype is obtained by equating the
Mach number of the model and its prototype.
Ma = V/c
where c is the speed of sound (343 m/s at 20°C) and V is the fluid velocity.
9.7 Case Studies
Physical model studies are widely used in the field of coastal engineering
to assess the stability and performance of structures. Typically to initiate
a model study, the scaling law to be followed is decided first. Figure 9.2
projects the prototype and model scale down version of a flaring shaped