M1L1 - Introduction to Thermodynamics and Review of Units/Dimensions Flashcards
Developed steam engines
Thomas Savery and Thomas Newcomen
Introduced thermodynamics concept
William Thompson (1st Baron Kelvin) and William John Macquorn Rankine
deals with the science of energy transformations, including heat and work, and the physical properties of substances that are involved in those
Thermodynamics
is one component of thermodynamics that deals with
the processes that transpire in every component of the system that include heat
engines, refrigeration, air conditioning, and combustion
Engineering thermodynamics
is a macroscopic approach to the study of
thermodynamics that does require a knowledge of the behavior of individual
particles of a substance
Classical thermodynamics
is a microscopic approach and more elaborative that is
based on the average behavior of large groups of individual particles of a
substance
Statistical Thermodynamics
Any
physical quantity can be characterized by
dimensions
The magnitude assigned
to the dimensions are called
units
Simple and logical system based on a
decimal relationship between various units
Metric SI or the International System
No apparent
systematic numerical base, and various units are arbitrarily related
English System or United States Customary System (USCS)
every
term in an equation must have the same unit
dimensionally homogenous
are identically equal to 1 and are unitless, and thus such
ratios (or their inverse) can be inserted conveniently into any calculation to
properly convert units
unity conversion ratios
defined as a quantity of matter or a region in
space chosen for study.
system
consists of a fixed
amount of mass, and no mass can cross its boundary,
but energy, in the form of heat or work, can cross the
boundary
closed system (control mass)
a special
case closed system in which
even energy is not allowed to
cross the boundary
isolated system
a properly
selected region in space where both mass and
energy can cross the boundary
open system (control volume)
The
boundaries of a control
volume are called
control surface
Any
characteristics of a system is called
property
are those independent of the
mass of the system
intensive properties
are those whose values depend
on the size, or extent, of the system
extensive properties
Extensive
properties per unit mass are called
specific properties
Matter
can be conveniently viewed as a continuous,
homogeneous matter with no holes, that is a
continuous
is defined as mass per unit volume
density
The reciprocal of density, which is also defined as volume per unit mass
specific volume
defined as the ratio of density of a substance
to the density of some standard substance at a specified temperature, which is
usually water at 44°C
specific gravity
The
weight of a unit volume of a substance is called specific
specific weight
indicates the thermal state of the system and its ability to exchange
energy with a substance to which it is in contact
temperature
Two
bodies are said to have reached BLANK if both have the same or
equal temperature
thermal equilibrium
states that if
two bodies are in thermal equilibrium with a third
body, they are also in thermal equilibrium with
each other This
zeroth law of thermodynamics
SI temperature scale in which freezing and boiling points
were originally assigned as 0 and 100°C, respectively.
celsius scale
English temperature scale in which freezing and boiling
points are 32 and 212°F, respectively.
fahrenheit scale
a temperature scale that is independent
of the properties of any substances which is developed later in conjunction with
the second law of thermodynamics.
thermodynamic temperature scale
defined as a normal force exerted by a system per unit area.
pressure
The
actual pressure at a given position is called BLANK and it is measured relative to the
absolute vacuum.
absolute pressure
the force exerted by the
atmosphere per unit area.
atmospheric pressure
The
difference between the atmospheric and
absolute pressures is called
gage pressure
when the absolute pressure is lower than
the atmospheric pressure, the negative gage
pressure is termed as vacuum
vacuum pressure
The
BLANK of the system is its condition described by set of property values
state
In
an BLANK, there are no unbalanced potentials (or driving forces)
within the system, and it does not experience changes when it is isolated from its
surroundings
equilibrium state
Temperature is the same throughout the entire
system.
thermal equilibrium
No change in pressure at any point of the system
with time.
mechanical equilibrium
When a system involves two phases, and the mass of
each phase reaches equilibrium level and stays there
phase equilibrium
Chemical composition does not change with time or
no chemical reactions occur.
chemical equilibrium
The
number of properties required to fix the state of a system is given by the state
postulate
“The state of a simple compressible system is completely specified by two independent,
intensive properties.”
A
system is called a BLANK in the absence of electrical,
magnetic, gravitational, motion, and surface tension effects.
simple compressible system
Two
properties are BLANK if one property can be varied while the other
one is held constant.
independent
Any
change that a system undergoes from one
equilibrium state to another is called a
process
The
series of states through which a system passes during
a process is called the BLANK of the process
path
When
a process proceeds in such a manner that the
system remains infinitesimally close to an
equilibrium state at all times, it is called a
quasi - static or quasi - equilibrium process
process is a process during which the temperature remains constant.
isothermal
process is a process during which pressure remains constant.
isobaric
process is a process during which the specific volume remains constant.
isochoric (isometric)
A
system is said to have undergone a BLANK if it returns to its initial state at the end of
the process
cycle
defined as a process during which a fluid flows through a
control volume steadily, or properties does not change with time.
steady - flow process
