Chemical Engineering Exam  >  Chemical Engineering Questions  >   One end of a long rod is inserted into a fur... Start Learning for Free
One end of a long rod is inserted into a furnace while the other projects into ambient air. Under steady state the temperature of the rod is measured at two points 75 mm apart and found to be 125°C and 88.5°C.respectively, while the ambient temperature is 20°C. If the rod is 25 mm in diameter and h is 23.36 W/m2-K, find the thermal conductivity of the rod material.
  • a)
    115
  • b)
    116
Correct answer is between '115,116'. Can you explain this answer?
Verified Answer
One end of a long rod is inserted into a furnace while the other proj...
The temperature distribution is given by
At x = 0, ? = ?0, and at x → ∞,? = 0
∴ C2 = 0
? = C1e-mx
Let ? be the distance between the two points where the temperatures are measured. Then,
?1 = ?0e-mx1
ml = 0.427
View all questions of this test
Most Upvoted Answer
One end of a long rod is inserted into a furnace while the other proj...
Given:
- Temperature at point A: 125°C
- Temperature at point B: 88.5°C
- Ambient temperature: 20°C
- Distance between points A and B: 75 mm
- Diameter of the rod: 25 mm
- Heat transfer coefficient (h): 23.36 W/m^2-K

To Find:
Thermal conductivity of the rod material

Assumptions:
- Steady-state conditions
- One-dimensional heat transfer
- Negligible heat generation within the rod

Solution:

Step 1: Calculate the temperature difference
The temperature difference across the rod can be calculated using the equation:

ΔT = T_A - T_B

ΔT = 125°C - 88.5°C = 36.5°C

Step 2: Calculate the heat transfer rate
The heat transfer rate through the rod can be calculated using the equation:

Q = h * A * ΔT

Where:
- Q is the heat transfer rate
- h is the heat transfer coefficient
- A is the surface area of the rod
- ΔT is the temperature difference

The surface area of the rod can be calculated using the equation:

A = π * d * L

Where:
- A is the surface area
- d is the diameter of the rod
- L is the distance between the two temperature points

Substituting the given values:

A = π * (25 mm)^2 * (75 mm)

A = 58823.53 mm^2

Converting the surface area to m^2:

A = 0.05882353 m^2

Now, substituting the values into the heat transfer rate equation:

Q = 23.36 W/m^2-K * 0.05882353 m^2 * 36.5°C

Q = 48.024 W

Step 3: Calculate the thermal conductivity
The heat transfer rate can also be expressed as:

Q = k * A * ΔT / L

Where:
- k is the thermal conductivity

Rearranging the equation to solve for k:

k = Q * L / (A * ΔT)

Substituting the given values:

k = 48.024 W * 0.075 m / (0.05882353 m^2 * 36.5°C)

k = 115.976 W/m-K

Therefore, the thermal conductivity of the rod material is approximately 116 W/m-K.
Explore Courses for Chemical Engineering exam

Similar Chemical Engineering Doubts

One end of a long rod is inserted into a furnace while the other projects into ambient air. Under steady state the temperature of the rod is measured at two points 75 mm apart and found to be 125°C and 88.5°C.respectively, while the ambient temperature is 20°C. If the rod is 25 mm in diameter and h is 23.36 W/m2-K, find the thermal conductivity of the rod material.a)115b)116Correct answer is between '115,116'. Can you explain this answer?
Question Description
One end of a long rod is inserted into a furnace while the other projects into ambient air. Under steady state the temperature of the rod is measured at two points 75 mm apart and found to be 125°C and 88.5°C.respectively, while the ambient temperature is 20°C. If the rod is 25 mm in diameter and h is 23.36 W/m2-K, find the thermal conductivity of the rod material.a)115b)116Correct answer is between '115,116'. Can you explain this answer? for Chemical Engineering 2024 is part of Chemical Engineering preparation. The Question and answers have been prepared according to the Chemical Engineering exam syllabus. Information about One end of a long rod is inserted into a furnace while the other projects into ambient air. Under steady state the temperature of the rod is measured at two points 75 mm apart and found to be 125°C and 88.5°C.respectively, while the ambient temperature is 20°C. If the rod is 25 mm in diameter and h is 23.36 W/m2-K, find the thermal conductivity of the rod material.a)115b)116Correct answer is between '115,116'. Can you explain this answer? covers all topics & solutions for Chemical Engineering 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for One end of a long rod is inserted into a furnace while the other projects into ambient air. Under steady state the temperature of the rod is measured at two points 75 mm apart and found to be 125°C and 88.5°C.respectively, while the ambient temperature is 20°C. If the rod is 25 mm in diameter and h is 23.36 W/m2-K, find the thermal conductivity of the rod material.a)115b)116Correct answer is between '115,116'. Can you explain this answer?.
Solutions for One end of a long rod is inserted into a furnace while the other projects into ambient air. Under steady state the temperature of the rod is measured at two points 75 mm apart and found to be 125°C and 88.5°C.respectively, while the ambient temperature is 20°C. If the rod is 25 mm in diameter and h is 23.36 W/m2-K, find the thermal conductivity of the rod material.a)115b)116Correct answer is between '115,116'. Can you explain this answer? in English & in Hindi are available as part of our courses for Chemical Engineering. Download more important topics, notes, lectures and mock test series for Chemical Engineering Exam by signing up for free.
Here you can find the meaning of One end of a long rod is inserted into a furnace while the other projects into ambient air. Under steady state the temperature of the rod is measured at two points 75 mm apart and found to be 125°C and 88.5°C.respectively, while the ambient temperature is 20°C. If the rod is 25 mm in diameter and h is 23.36 W/m2-K, find the thermal conductivity of the rod material.a)115b)116Correct answer is between '115,116'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of One end of a long rod is inserted into a furnace while the other projects into ambient air. Under steady state the temperature of the rod is measured at two points 75 mm apart and found to be 125°C and 88.5°C.respectively, while the ambient temperature is 20°C. If the rod is 25 mm in diameter and h is 23.36 W/m2-K, find the thermal conductivity of the rod material.a)115b)116Correct answer is between '115,116'. Can you explain this answer?, a detailed solution for One end of a long rod is inserted into a furnace while the other projects into ambient air. Under steady state the temperature of the rod is measured at two points 75 mm apart and found to be 125°C and 88.5°C.respectively, while the ambient temperature is 20°C. If the rod is 25 mm in diameter and h is 23.36 W/m2-K, find the thermal conductivity of the rod material.a)115b)116Correct answer is between '115,116'. Can you explain this answer? has been provided alongside types of One end of a long rod is inserted into a furnace while the other projects into ambient air. Under steady state the temperature of the rod is measured at two points 75 mm apart and found to be 125°C and 88.5°C.respectively, while the ambient temperature is 20°C. If the rod is 25 mm in diameter and h is 23.36 W/m2-K, find the thermal conductivity of the rod material.a)115b)116Correct answer is between '115,116'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice One end of a long rod is inserted into a furnace while the other projects into ambient air. Under steady state the temperature of the rod is measured at two points 75 mm apart and found to be 125°C and 88.5°C.respectively, while the ambient temperature is 20°C. If the rod is 25 mm in diameter and h is 23.36 W/m2-K, find the thermal conductivity of the rod material.a)115b)116Correct answer is between '115,116'. Can you explain this answer? tests, examples and also practice Chemical Engineering tests.
Explore Courses for Chemical Engineering exam
Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
10M+ students study on EduRev