hydraulics
Why is the term "incompressible fluid" used for droplet liquids
They practically do not change their volume with changes in pressure
Which property characterizes droplet liquids?
Practically unchanged volume under external forces
How are fluids categorized in hydraulics?
As gas-forming fluids (gases) and droplet liquids (liquids)
What is the position of droplet liquids in terms of their physical properties and behavior?
Intermediate between gases and solid bodies
What are the fundamental properties of liquids?
Continuity and fluidity
When is continuity met in the case of liquids?
When the dimensions of considered volumes of liquid are much larger than the characteristics of molecules
What assumption is made in fluid mechanics regarding the molecular-atomic structure of matter?
The structure is treated as a continuous medium
What is fluidity related to?
Taking the shape of the container
Density and volume
How do liquids generally respond to shear deformations?
Little resistance, showing good mobility or fluidity
What concept is introduced to assess a liquid's ability to resist shear deformations?
Viscosity
What property is attributed to ideal fluids?
Absolute mobility and volume invariance
What does an ideal fluid not exhibit during motion?
Shear stresses
In which kind of fluid is there no internal friction?
Ideal fluids
What differentiates a real fluid from an ideal one?
Exhibits internal friction
What is the definition of fluids?
Substances that easily change their shape under surface and mass forces
How is the motion of fluids viewed in fluid mechanics?
As the motion of a continuous medium with changing properties
How is the density of a liquid medium at a given point defined?
As the limit that the average density within a given volume approaches as that volume tends to zero
What is the unit of measurement for density?
Kilograms per cubic meter (kg/m³)
How is specific weight expressed?
Newtons per cubic meter (N/m³)
How does density vary with changes in pressure and temperature for liquids
Decreases with increasing temperature and decreasing pressure
What is specific volume?
The volume per unit mass, which is the reciprocal of density
What does the density of a liquid depend on?
Pressure and temperature at that point
What parameter characterizes the relative change in the volume of a liquid for each unit change in pressure?
Coefficient of volumetric compression
What is used to quantify the compressibility of a liquid?
Bulk modulus of elasticity
What is the bulk modulus of elasticity?
The reciprocal of the coefficient of volumetric compression of the liquid
What does the coefficient of thermal expansion quantify?
The relative change in the volume of a liquid for each unit change in temperature
What is viscosity related to in fluids?
Resistance to shearing forces
How does the dynamic coefficient of viscosity change with increasing temperature for non-compressible fluids (liquids)?
Increases
How does the dynamic coefficient of viscosity change with pressure for gases?
Changes only slightly with pressure
How is Newton's law for internal friction in liquids different from the laws governing solid friction?
It is proportional to the relative velocity of the layers
What type of fluids adhere to Newton's law for internal friction?
Newtonian fluids
Which of the following do not adhere to Newton's law for internal friction?
Anomalous fluids
Give an example of fluids that do not adhere to Newton's law.
Clay solutions used in drilling oil wells and certain types of oil near freezing temperatures
What occurs in fluids that do not adhere to Newton's law when shear stresses reach a certain value?
Motion occurs
What are the three modes of motion when structural fluids flow through a pipeline?
Structural, laminar, and turbulent
What is the characteristic of structural flow?
Requires a certain initial pressure drop
How does laminar flow develop in a pipeline?
With an increase in pressure drop
What is the transitional flow regime between structural and laminar flow?
Laminar flow
How is turbulent flow characterized?
High velocity
What is the requirement for the transition from structural flow to laminar flow?
Increase in pressure drop
In which flow mode does a fluid act as a single entity, similar to a solid?
Turbulent
At what point does laminar flow transition into turbulent flow?
With higher velocities
Alongside rigid bodies, in nature, there exist deformable solids, liquids, and gases (the various states of matter).
All of the above
The mechanics of deformable solids is studied in the field of Mechanics of Materials.
Mechanics of Materials
The mechanics of fluids and gases are studied in the field of Fluid Mechanics (Hydromechanics).
Fluid Mechanics (Hydromechanics)
Hydromechanics is the science that deals with the equilibrium and motion of fluids.
Hydromechanics
Hydraulics is an applied science that studies the laws of motion and equilibrium of liquids and provides methods for applying these laws to solve specific technical problems.
Hydraulics
Fluid Kinematics: A branch of hydromechanics that studies the motion of fluids regardless of the acting forces. In fluid kinematics, the relationship between the geometric characteristics of motion and time is established.
Fluid Kinematics
Hydrostatics: This branch examines the laws of equilibrium (rest) of fluids.
Hydrostatics
Hydrodynamics: Hydrodynamics focuses on the laws governing the motion of fluids.
Hydrodynamics
Depending on whether the focus is on theoretical or applied aspects, the terms "theoretical hydromechanics" or "applied hydromechanics" are used.
Both theoretical and applied hydromechanics
Therefore, under the term "fluid," we will refer to both liquids and gases, considering droplet liquids as incompressible and gases as compressible fluids.
True
What term describes the ability of a submerged object to neither float nor sink when submerged to any depth?
Indifferent equilibrium
What is the term for the weight of a liquid displaced by an object submerged in it?
Buoyancy
What is the point of application of the resultant buoyant force called for a floating object?
Center of buoyancy (point D)
What is the distance between the metacenter and the center of gravity called?
Metacentric radius
Which of the following remains fixed during a heel of the object?
Center of gravity
What is the second type of equilibrium for a floating object?
Indifferent equilibrium
In Euler's method, how is the motion of the entire fluid characterized?
By constructing a velocity field
In Euler's method, what are the velocities at all points determined?
Functions of certain parameters
What is the fundamental difference between Euler's and Lagrange's methods for studying fluid motion?
The Euler's method studies motion at fixed points, while Lagrange's method tracks individual particles
What defines the change in velocity over time at a specific point in space?
Local acceleration
What is convective acceleration related to?
Changes in velocity concerning coordinates
In Euler's method, how is the motion of the entire fluid characterized?
By constructing a velocity field
What is the relationship between the Euler's method and the Lagrange's method?
They are mathematically related to each other
What are the main quantities considered in Euler's method for studying fluid motion?
Velocity components and pressure
How is velocity represented in Euler's method?
As a velocity field
What does local acceleration define?
The change in velocity concerning coordinates
What is the Lagrange's method primarily based on?
Tracking individual particles within the fluid
What is the law of Archimedes related to?
Buoyancy
What is the buoyant force also referred to as?
Supporting force
What does the buoyant force act on when an object is submerged in a fluid?
The object itself
In which case is an object in a state of indifferent equilibrium?
The specific weight of the body and the liquid are the same
When the specific weight of the body is greater than the specific weight of the liquid, what happens to the object?
It sinks
What happens when the specific weight of the body is less than the specific weight of the liquid?
The body will float
What is necessary for the equilibrium of an object submerged in a liquid?
The condition G=Fz
What does it mean for an object to be homogeneous?
It is filled with a substance of constant density throughout
In a non-homogeneous object, what happens to the points of application of the forces G and Fz?
They do not coincide
What is the term for the ability of a floating object to return to its equilibrium state when displaced?
Stability
What is the weight of the liquid displaced by a submerged object called?
Buoyancy
What is the point of application of the resultant buoyant forces called?
Center of buoyancy (point D)
What is the distance between the metacenter and the center of gravity called?
Metacentric radius
What remains in a fixed position during a heel?
Center of gravity C
What is the first type of equilibrium for a floating object?
Stable equilibrium
In an indifferent equilibrium, where are the metacenter and the center of gravity?
The metacenter and the center of gravity coincide
What is the third type of equilibrium for a floating object?
Unstable equilibrium
What is the branch of hydraulics that studies the laws of fluid motion called?
Hydrodynamics
What are the two main problems considered when studying the motion of fluids?
Forces acting on the fluid and hydrodynamic characteristics of the flow
In the context of an ideal fluid, what is the property of hydrodynamic pressure?
It possesses the same properties and meaning as hydrostatic pressure
What are the equations considered in hydraulics to determine velocity components and pressure?
The equation of incompressibility and continuity, differential equations of motion, and the equation of the conservation of specific energy
What are the two methods of investigation used when studying fluid motion?
Lagrange's method and Euler's method
In Lagrange's method, how is the motion of fluid particles tracked?
Specific particles are marked at an initial moment of time, and their motion is tracked over time
What is the primary characteristic of Euler's method?
It involves studying changes over time at fixed points in space
How is velocity represented in Euler's method?
As a velocity field
What is the relationship between the Euler's method and the Lagrange's method?
They are mathematically related to each other
What defines the change in velocity over time at a specific point in space?
Local acceleration
What does convective acceleration define?
The change in velocity concerning coordinates
What does hydrostatics primarily study in fluid mechanics?
Fluids at rest and their behavior under the influence of gravitational forces
What is the main aim of hydrostatics?
Analyzing and describing the equilibrium and pressure distribution of fluids at rest
What are mass forces in fluid mechanics related to?
The mass of the fluid