1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Lesechka [4]
3 years ago
12

In the well-insulated trans-Alaska pipeline, the high viscosity of the oil and long distances cause significant pressure drops,

and it is reasonable to question whether flow work would be significant. Consider an 150 km length of pipe of diameter 1.2 m, with oil flow rate 500 kg/s. The oil properties are 900 kg/m3, 2000 J/kg·K, 0.765 N·s/m2. Calculate the pressure drop, the flow work, and the temperature rise caused by the flow work. Recall from chapter 1, for steady flow, one inlet, one outlet, no heat transfer, no work, and negligible kinetic and protential energy changes, the enthalpy of the fluid remains constant. Enthalpy is the sum of internal energy and flow work.
Engineering
1 answer:
s2008m [1.1K]3 years ago
5 0

Our values are defined by,

L=150*10^3m

\Phi = 1.2m

\dot{m}=700kg/s

\rho_o=900km/m^3

Sp=2000J/KgK

\mu_k = 0.765Ns/m^2

With this data we can easily calculate first the mean velocity of the flow,

The velocity is given by,

\nu=\frac{\dot{m}}{\rho_o A_c}

\nu = \frac{\dot{m}}{\rho_o \pi/4\Phi^2}

\nu = \frac{4*700}{900\pi(1.2)^4}

\nu=0.688m/s

With the mean velocity is now possible determine if the flow is Laminar or turbulent, for that we need Number Reynolds.

Remember that a Laminar Flow is given when Reynolds number is minor to 2300, then

Re_x = \frac{4\dot{m}}{\pi D\mu_k}

Re_x = \frac{4*700}{\pi*1.2*0.765}

Re_x = 970.8798

Re_x < 2300, then the flow is laminar.

For this section we will consider the Pressure drop to calculate the flow Work and the Total Energy conservation of this flow.

To calculate the Pressure drop we need the Friction factor, which is given by,

f= \frac{64}{Re}=\frac{64}{970.8789}

f= 0.06591

Then the Pressure drop is given by,

\Delta P = \frac{f\rho_o \nu^2 L}{2D}

\Delta P = \frac{0.06591*900*(0.688)^2*183*10^3}{2*1.2}

\Delta P = 2.141*10^6Pa

We can now calculate the Flow Work given by,

W_f = \frac{\Delta P\dot{m}}{\rho_o}

W_f = \frac{2.141*10^6*700}{900}

W_f = 1.6651*10^6J

From energy conservation we have

W_f=q

W_f = \dot{m}c_p\Delta T

Re-arrange for \Delta T

\Delta T = \frac{W_f}{\dot{m}c_p}

\Delta T = \frac{1.56*10^6}{700*2000}

\Delta T = 1.1894\°c

You might be interested in
Electricians will sometimes call ______ "disconnects" or a "disconnecting means."
Natali5045456 [20]
I want to say D but i’m not 100% sure
5 0
2 years ago
You are an engineer working in a auto crash test lab. Some members of your team have raised objections against the use of cadave
Nikolay [14]

Answer: Application.

Explanation:

The question on wether to contine the use of cadavers in the lab for test is being centered around its application. Cadaver which is same as a corpse or dead body is used in crash site during automobil test in lab, some of this cadavers are been disrespected with their applications in the automobile industries because many didn’t consent to be used in those experiments or test.

5 0
3 years ago
Which of the following refers to a full-scale version of a product used to validate performance?
kompoz [17]
I’m thinking it would be c sorry if it’s wrong .
4 0
3 years ago
Read 2 more answers
Air at 40C flows over a 2 m long flat plate with a free stream velocity of 7 m/s. Assume the width of the plate (into the paper)
mezya [45]

Complete Question

Air at 40C flows over a 2 m long flat plate with a free stream velocity of 7m/s. Assume the width of the plate (into the paper) is 0.5 m. If the plate is at a co temperature of 100C,find:

The total heat transfer rate from the plate to the air

Answer:

q=1.7845

Explanation:

From the question we are told that:

Air Temperature T_1=40c

Length l=2m

Velocity v=7m/s

Width w=0.5

Constant temperature T_t= 100C

Generally the equation for Total heat Transfer is mathematically given by

 q=hA(T_s-T_\infty)

Where

h=Convective heat transfer coefficient

 h=29.9075w/m^2k

Therefore

 q=h(L*B)(T_s-T_\infty)

 q=29.9075*(2*0.5)(100+273-(40+273))

 q=1794.45w

 q=1.7845

5 0
3 years ago
Explain about Absolute viscosity, kinematic viscosity and SUS?
ArbitrLikvidat [17]

Answer:

Absolute viscosity is the evaluation of the resistance (INTERNAL) of the fluid  flow

Kinematic viscosity relates to the dynamic viscosity and density proportion.

SUS stands for Sabolt Universal Seconds. it is units which described the variation of oil viscosity

Explanation:

Absolute viscosity is the evaluation of the resistance (INTERNAL) of the fluid  flow, whereas Kinematic viscosity relates to the dynamic viscosity and density proportion. fluid with distinct kinematic viscosities may have similar dynamic viscosities and vice versa.Dynamic viscosity provides you details of  power required to make the fluid flow at some rate, however kinematic viscosity shows how quick the fluid moves when applying a certain force.

SUS stands for Sabolt Universal Seconds. it is units which described the variation of oil viscosity when change with change in temperature. it is measured by using viscosimeter.

3 0
3 years ago
Other questions:
  • Remy noticed that after oiling his skateboard wheels, it was easier to reach the speeds he needed to perform tricks. How did the
    6·1 answer
  • How much work is performed if a 400 lb weight is lifted 10 ft ?
    8·1 answer
  • I'm really bad at measurements so I don't understand this.
    12·1 answer
  • Can a real refrigerator have higher COP than the COP of the Carnot refrigerator?
    7·2 answers
  • 2.31 LAB: Simple statistics Part 1 Given 4 integers, output their product and their average, using integer arithmetic. Ex: If th
    5·2 answers
  • The traffic lights are not functioning.
    7·1 answer
  • What drives up the cost of consumables?
    6·1 answer
  • Contrast the electron and hole drift velocities through a 10 um (micro meter) layer of intrinsic silicon across which a voltage
    11·1 answer
  • Steam enters a heavily insulated throttling valve at 11 MPa, 600°C and exits at 5.5 MPa. Determine the final temperature of the
    14·1 answer
  • What is equation for surface area?
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!