# 
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"Project-Id-Version: Modelica by Example 0.2.1\n"
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"Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
"Language-Team: LANGUAGE <LL@li.org>\n"
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#: ../../source/components/connectors/fluid_connectors.rst:4
msgid "Fluid Connectors"
msgstr ""

#: ../../source/components/connectors/fluid_connectors.rst:6
msgid ""
"One area that Modelica has been widely used in is the modeling of various "
"types of fluid systems.  We saw in the previous section how to create "
"connectors for various :ref:`simple-domains`.  But what makes Modelica so "
"compelling for fluid systems is the ability to create more complex "
"connectors involving multiple conserved quantities simultaneously.  Such "
"connectors are essential for modeling fluid systems, where a single "
"connector might involve the flow of mass, momentum, energy and/or species.  "
"Such cases require the definition of rich connectors types."
msgstr ""

#: ../../source/components/connectors/fluid_connectors.rst:25
msgid "Incompressible Fluids"
msgstr ""

#: ../../source/components/connectors/fluid_connectors.rst:27
msgid ""
"Modeling of incompressible fluids is very useful in a number of engineering "
"applications, most notably hydraulically actuated systems. We'll start by "
"presenting a simple connector that can be used to model incompressible "
"systems, but with some important caveats."
msgstr ""

#: ../../source/components/connectors/fluid_connectors.rst:32
msgid "Consider the following connector definition:"
msgstr ""

#: ../../source/components/connectors/fluid_connectors.rst:38
msgid ""
"As we saw in our discussion of :ref:`simple-domains`, we see the familiar "
"pattern of an across variable and a through variable.  In this case the "
"across variable is ``p`` (the pressure) and the through variable is ``q`` "
"(the volumetric flow rate).  But this connector is different from all the "
"previous examples because the ``flow`` variable is **not** the time "
"derivative of a conserved quantity, since volume is not a conserved "
"quantity."
msgstr ""

#: ../../source/components/connectors/fluid_connectors.rst:46
msgid ""
"This connector works **as long as the fluid being modeled is "
"incompressible**.  To understand why, consider the following equation:"
msgstr ""

#: ../../source/components/connectors/fluid_connectors.rst:53
msgid ""
"where :math:`q_1`, :math:`q_2`, :math:`q_3` and :math:`q_1` represent "
"volumetric flow terms (*i.e.,* each has units of :math:`m^3/s`).  In "
"general, this equation does not qualify as a conservation equation because "
"volume is (again, in general) not conserved.  However, if we know that each "
"of these flows is an incompressible fluid, then we can multiply the entire "
"equation by the density of that incompressible fluid, *i.e.,*"
msgstr ""

#: ../../source/components/connectors/fluid_connectors.rst:65
msgid ""
"Now each of these terms has units of :math:`kg/s` which is a conservation "
"equation because mass is a conserved quantity.  However, **if you use this "
"connector definition with a fluid that has any significant degree of "
"compressibility, you will get the wrong answer.**"
msgstr ""

#: ../../source/components/connectors/fluid_connectors.rst:71
msgid ""
"Such a connector definition is useful for relatively simple incompressible "
"fluid flow networks because it can frequently describe the behavior of the "
"system without having to specify (or know) the density of the working fluid."
"  However, this kind of approach is inherently limiting so it should only be"
" used in situations where it solves more problems than it creates."
msgstr ""

#: ../../source/components/connectors/fluid_connectors.rst:79
msgid "Compressible Fluids"
msgstr ""

#: ../../source/components/connectors/fluid_connectors.rst:81
msgid ""
"While the previous connector definition should be strictly used for :ref"
":`incompressible-fluids`, the following connector is more general:"
msgstr ""

#: ../../source/components/connectors/fluid_connectors.rst:88
msgid ""
"This connector can be used for **both** incompressible or compressible "
"fluids.  This is because it doesn't make any inherent assumptions about the "
"compressibility of the fluid.  Note that the across variable, ``p``, is "
"still pressure, but the through variable, ``m_dot``, is a mass flow rate.  "
"As such, the through variable conforms to the convention that a through "
"variable should be the time derivative of a conserved quantity (in this "
"case, mass).  So there are no implicit assumptions in this connector, which "
"is why it can be used to model fluid flow of both compressible and "
"incompressible fluids."
msgstr ""

#: ../../source/components/connectors/fluid_connectors.rst:98
msgid ""
"This connector isn't really fundamentally different from the connectors "
"associated with :ref:`simple-domains`, but it appears in this section "
"because it is a stepping stone to the next example."
msgstr ""

#: ../../source/components/connectors/fluid_connectors.rst:103
msgid "Thermo-Fluid Modeling"
msgstr ""

#: ../../source/components/connectors/fluid_connectors.rst:105
msgid ""
"So far in this section, we've presented a connector for incompressible fluid"
" systems, ``Incompressible``, and a more general connector, "
"``GenericFluid``.  But in both of these cases, the only conserved quantity "
"considered was mass.  Nowhere in these previous connectors is there any "
"reference to or allowance for modeling the **temperature** of the fluid."
msgstr ""

#: ../../source/components/connectors/fluid_connectors.rst:112
msgid ""
"There are many applications where the temperature of the working fluid is "
"critical.  In some cases, the temperature changes the density of the working"
" fluid.  In other cases, the temperature may trigger a phase change (*e.g.,*"
" from liquid to gas).  Temperature can also affect other critical properties"
" of the fluid like viscosity, which have a significant impact on the "
"performance of, for example, lubrication systems.  As a result, those "
"previous connector definitions would be inadequate for modeling systems "
"where the temperature of the working fluid had any significant impact on the"
" system behavior."
msgstr ""

#: ../../source/components/connectors/fluid_connectors.rst:123
msgid ""
"To predict the temperature of a working fluid, it is necessary to track the "
"energy that flows with the fluid as it flows through a network.  To do this,"
" the connector definition must be augmented to include energy, alongside "
"mass, as a conserved quantity that flows through the connector.  The "
"following connector definition does just that:"
msgstr ""

#: ../../source/components/connectors/fluid_connectors.rst:134
msgid ""
"Note that this connector includes **two** variables that have the ``flow`` "
"qualifier, ``m_dot`` and ``q``.  These represent the flow of mass and "
"energy, respectively.  Each of these is paired with an across variable.  One"
" of those across variables is the pressure, ``p``, just as we saw in the "
"previous connectors in this section.  The other across variable, ``T``, is "
"the temperature of the working fluid."
msgstr ""

#: ../../source/components/connectors/fluid_connectors.rst:16
msgid ""
"We'll start this section with a discussion of basic connectors very similar "
"to the ones used for :ref:`simple-domains`.  But we will conclude with a "
"connector that is fundamentally different from the previous examples because"
" it describes a connector that involves the conservation of both mass and "
"energy."
msgstr ""

#~ msgid ""
#~ "We'll start this section with a discussion of basic connectors very similar "
#~ "to the ones used for :ref:`simple-domains`.  But we will conclude with a "
#~ "connector that is fundamentally different than the previous examples because"
#~ " it describes a connector that involves the conservation of both mass and "
#~ "energy."
#~ msgstr ""
