2021-23 Unit 6 LA A Project Research Unknown
I work in a research and development lab.It's time for me to take control of my own
project management, according to my boss. I have successfully conducted literature
research to produce an investigative project proposal and plan based on my proposal,
based on suggestions from my supervisor and my own interests in the fields of physics.
Now that my plan is in motion, I'll evaluate my project.
Investigative project
My project proposal is to determine the terminal velocity of a spherical material (e.g. a
ball) using a viscosity tube. Hypothesis, as I increase the temperature of the material,
the lower the viscosity meaning it has a lower resistance flow while the terminal velocity
increases.
Part A.P2 awarded
Aims
The aims of my investigation project proposal are:
- To determine the viscosity of lubricating oil at high temperature
- Determine when the material reaches terminal velocity.
- At what temperature does lubricant oil work best at
- To draw a graph to determine the best value of terminal velocity
Objectives
The objective of my project proposal is to work out the viscosity and terminal velocity at
different temperatures of a substance (oil). Another objective of my project proposal is
to compare viscosities of the oil at different temperatures. To find out the viscosity of
lubricating oil and what temperature it works best at.
Part A.M2
Fluid flow and fluid flow patterns
In order for a fluid to flow, layers of molecules must slide over one another. A streamline
or laminar flow occurs when motion only moves in the direction of the applied stress and
is characterised by slow, gentle flow. Because of the internal friction known as viscous
drag between the layers, this ordered motion does not absorb all of the energy present,
but it is still the flow that uses the least amount of energy (Curley, n.d.) (Lewis, n.d.).
Using more than one reference to prove a concept shows the reliability of it. When there
is streamline flow, the lines of flow are all parallel and are easily visible by adding a dye
or by observing the movement of the particles carried by the liquid. where a solid and
liquid are in contact (stationary if it is the bank of a river). The speeds of the layers
gradually alter as you move across the direction of flow through a liquid. As the velocity
gradient rises and the viscous drag forces increase, turbulent flow starts to appear
(Curley, n.d.). Any obstruction or sharp corner that disrupts the fluid's smooth flow can
cause turbulence, which will then spread to the nearby areas. The drag forces have a
natural tendency to cause the fluid to rotate in some places. Because turbulent flow
absorbs much more energy than smooth flow, the effective drag force also increases
significantly (Curley, n.d.).
Part A.M1
The equation known as Dary's law quantifies the ease with which a fluid can pass
through a porous substance, such as rock. Its foundation is the idea that the relationship
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, 2021-23 Unit 6 LA A Project Research Unknown
between flow and pressure between two points is a straight line. Permeability is the
name of the interconnectivity metric (whitaker 2006).
Terminal velocity
The aim of this investigation is to find out the viscosity of different materials and to
determine the time to reach terminal velocity, Terminal velocity is defined as the highest
velocity attained by an object falling through a fluid (Glenn 2009) another source that
shows what terminal velocity is the fastest possible speed at which an object can fall
through a liquid the greater the drag force (“Terminal velocity”, n.d.) This shows the
reliability of the source as it was published in 2012 meaning it is recent. The ability of
fluids, such as liquids and gases, to move or flow and further transmit pressure, heat, or
simply deliver quantities of substance to a new location makes them useful in systems. A
fluid's drag force on an object that has been released from rest increases as it falls at a
faster rate. The net force acting on the object is equal to the sum of the drag force and
the force of gravity acting on it. As the drag force rises, the resulting force falls and the
acceleration as it falls decreases.if it keeps falling, it will eventually reach terminal
speed, which is when the drag force acting on it equals and opposes the weight. Then, it
experiences zero acceleration, and it falls with a constant speed (“Section B: Energy
Transfer - Energy Education: Concepts and Practices | UWSP”, n.d.).
Viscosity and newton’s Law
Viscosity and the viscous resistance to flow is dependent on the molecular chemistry of liquids, so
some liquids are more viscous than others; some liquids are less resistant to flow than others.
Therefore it is very useful to have a measure of viscosity, in order to compare them. This such
behaviour in liquids was first studied by sir Isaac Newton, who defined a coefficient of dynamic
viscosity, Ƞ, which is fundamental to exploring the flow of fluid (Kalipatnapu 2020). Here again using a
recent reference shows how it's up to date and reliable. The sliding of the layers of liquid over one
another generates a resistance force, this stress which is involved in shear stress, equal to the size of
that viscous drag force divided by the area of contact between the sliding layers. The strain in this
process is a measure of the rate of shear strain, which is another name for the velocity gradient
across the streams of flow (Kalipatnapu 2020). The relationship between a fluid's shear stress and
shear rate when it is under mechanical stress is described by Newton's law of viscosity. For a given
temperature and pressure, the ratio of shear stress to shear rate is constant and is known as the
viscosity or coefficient of viscosity (F, Gerorge, and Qurshi 2013).
Part A.P1, Part A.M1, Part A.M2
Shearof dynamic viscosity,Ƞ =
Coefficient
Newton’s stress, T
Rate of shear
Law of strain
viscosity, Kinematic Viscosity, V=ߎ
p
Where:
Wh 1)V= is the kinematic viscosity
ere, 2)ߎ is the dynamic viscosity
. Visc 3)p is the density of the fluid
Shear (Lewis 2015)
osity
stress=
Rate of shear
F/A
deformation 2
