Chemical Engineering Exam > Chemical Engineering Questions > A coaxial tube counter flow heat exchanger i...
Start Learning for Free
A coaxial tube counter flow heat exchanger is used to cool 0.03 kg/s of benzene from 360 K to 310 K with a counter flow of 0.02 kg/s of water initially at . If the inner tube outside diameter is 2 cm and the overall heat transfer coefficient based on outside area is 650 , determine the required length of the exchanger. Take the specific heats of benzene and water as 1880 and 4175 J/kg‐K, respectively.
(B) 2.60
Correct answer is between ','. Can you explain this answer?
Verified Answer
A coaxial tube counter flow heat exchanger is used to cool 0.03 kg/s ...
By energy balance,
Q = mhcp(Th1 - Th2) = mccc(Tc2 - Tc1)
Q = 0.03 x 1880(360 - 310)
= 0.02 x 1475(Tc2 - 290)
Q = 2820 w,Tc2 = 323.8 K
ΔTi = 310 -290 ΔTe = 360 - 323.8
= 20 = 36.2
LMTD(ፀm) = 36.2 - 20/ In 36.2/20 = 27.3 K
Q = UoAo(θm) = UoπdoL(θm)
L = 2820/650 x π x 0.02 x 27.3 = 2.53 m
This question is part of UPSC exam. View all Chemical Engineering courses
Most Upvoted Answer
A coaxial tube counter flow heat exchanger is used to cool 0.03 kg/s ...
Solution:
Given data:
Mass flow rate of benzene, m1 = 0.03 kg/s
Inlet temperature of benzene, T1 = 360 K
Outlet temperature of benzene, T2 = 310 K
Mass flow rate of water, m2 = 0.02 kg/s
Inlet temperature of water, T3 = 290 K
Outer diameter of the inner tube, d0 = 2 cm = 0.02 m
Overall heat transfer coefficient based on outside area, Uo = 650 W/m2-K
Specific heat of benzene, Cp1 = 1880 J/kg-K
Specific heat of water, Cp2 = 4175 J/kg-K
We can use the following equation to calculate the length of the heat exchanger:
Q = Uo x Ao x LMTD
Where,
Q = Heat transfer rate = m1 x Cp1 x (T1 - T2) = m2 x Cp2 x (T3 - T4)
Ao = Outside surface area of the inner tube = π x d0 x L
LMTD = Logarithmic mean temperature difference = (ΔT1 - ΔT2) / ln(ΔT1 / ΔT2)
ΔT1 = T1 - T3
ΔT2 = T2 - T4
Assuming that the outlet temperature of water, T4 is equal to the inlet temperature, T3, we can solve for L as follows:
m1 x Cp1 x (T1 - T2) = m2 x Cp2 x (T3 - T4)
L = Q / (Uo x Ao x LMTD)
ΔT1 = 360 K - 290 K = 70 K
ΔT2 = 310 K - 290 K = 20 K
LMTD = (70 - 20) / ln(70 / 20) = 39.2 K
Ao = π x 0.02 m x L = 0.04πL
Substituting the values in the above equations, we get:
L = (0.03 kg/s x 1880 J/kg-K x 50 K) / (650 W/m2-K x 0.04π x 39.2 K)
L = 2.60 m
Therefore, the required length of the heat exchanger is 2.60 m.
Given data:
Mass flow rate of benzene, m1 = 0.03 kg/s
Inlet temperature of benzene, T1 = 360 K
Outlet temperature of benzene, T2 = 310 K
Mass flow rate of water, m2 = 0.02 kg/s
Inlet temperature of water, T3 = 290 K
Outer diameter of the inner tube, d0 = 2 cm = 0.02 m
Overall heat transfer coefficient based on outside area, Uo = 650 W/m2-K
Specific heat of benzene, Cp1 = 1880 J/kg-K
Specific heat of water, Cp2 = 4175 J/kg-K
We can use the following equation to calculate the length of the heat exchanger:
Q = Uo x Ao x LMTD
Where,
Q = Heat transfer rate = m1 x Cp1 x (T1 - T2) = m2 x Cp2 x (T3 - T4)
Ao = Outside surface area of the inner tube = π x d0 x L
LMTD = Logarithmic mean temperature difference = (ΔT1 - ΔT2) / ln(ΔT1 / ΔT2)
ΔT1 = T1 - T3
ΔT2 = T2 - T4
Assuming that the outlet temperature of water, T4 is equal to the inlet temperature, T3, we can solve for L as follows:
m1 x Cp1 x (T1 - T2) = m2 x Cp2 x (T3 - T4)
L = Q / (Uo x Ao x LMTD)
ΔT1 = 360 K - 290 K = 70 K
ΔT2 = 310 K - 290 K = 20 K
LMTD = (70 - 20) / ln(70 / 20) = 39.2 K
Ao = π x 0.02 m x L = 0.04πL
Substituting the values in the above equations, we get:
L = (0.03 kg/s x 1880 J/kg-K x 50 K) / (650 W/m2-K x 0.04π x 39.2 K)
L = 2.60 m
Therefore, the required length of the heat exchanger is 2.60 m.
|
|
Explore Courses for Chemical Engineering exam
|
|
Similar Chemical Engineering Doubts
A coaxial tube counter flow heat exchanger is used to cool 0.03 kg/s of benzene from 360 K to 310 K with a counter flow of 0.02 kg/s of water initially at . If the inner tube outside diameter is 2 cm and the overall heat transfer coefficient based on outside area is 650 , determine the required length of the exchanger. Take the specific heats of benzene and water as 1880 and 4175 J/kg‐K, respectively.(B) 2.60Correct answer is between ','. Can you explain this answer?
Question Description
A coaxial tube counter flow heat exchanger is used to cool 0.03 kg/s of benzene from 360 K to 310 K with a counter flow of 0.02 kg/s of water initially at . If the inner tube outside diameter is 2 cm and the overall heat transfer coefficient based on outside area is 650 , determine the required length of the exchanger. Take the specific heats of benzene and water as 1880 and 4175 J/kg‐K, respectively.(B) 2.60Correct answer is between ','. 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 A coaxial tube counter flow heat exchanger is used to cool 0.03 kg/s of benzene from 360 K to 310 K with a counter flow of 0.02 kg/s of water initially at . If the inner tube outside diameter is 2 cm and the overall heat transfer coefficient based on outside area is 650 , determine the required length of the exchanger. Take the specific heats of benzene and water as 1880 and 4175 J/kg‐K, respectively.(B) 2.60Correct answer is between ','. 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 A coaxial tube counter flow heat exchanger is used to cool 0.03 kg/s of benzene from 360 K to 310 K with a counter flow of 0.02 kg/s of water initially at . If the inner tube outside diameter is 2 cm and the overall heat transfer coefficient based on outside area is 650 , determine the required length of the exchanger. Take the specific heats of benzene and water as 1880 and 4175 J/kg‐K, respectively.(B) 2.60Correct answer is between ','. Can you explain this answer?.
A coaxial tube counter flow heat exchanger is used to cool 0.03 kg/s of benzene from 360 K to 310 K with a counter flow of 0.02 kg/s of water initially at . If the inner tube outside diameter is 2 cm and the overall heat transfer coefficient based on outside area is 650 , determine the required length of the exchanger. Take the specific heats of benzene and water as 1880 and 4175 J/kg‐K, respectively.(B) 2.60Correct answer is between ','. 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 A coaxial tube counter flow heat exchanger is used to cool 0.03 kg/s of benzene from 360 K to 310 K with a counter flow of 0.02 kg/s of water initially at . If the inner tube outside diameter is 2 cm and the overall heat transfer coefficient based on outside area is 650 , determine the required length of the exchanger. Take the specific heats of benzene and water as 1880 and 4175 J/kg‐K, respectively.(B) 2.60Correct answer is between ','. 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 A coaxial tube counter flow heat exchanger is used to cool 0.03 kg/s of benzene from 360 K to 310 K with a counter flow of 0.02 kg/s of water initially at . If the inner tube outside diameter is 2 cm and the overall heat transfer coefficient based on outside area is 650 , determine the required length of the exchanger. Take the specific heats of benzene and water as 1880 and 4175 J/kg‐K, respectively.(B) 2.60Correct answer is between ','. Can you explain this answer?.
Solutions for A coaxial tube counter flow heat exchanger is used to cool 0.03 kg/s of benzene from 360 K to 310 K with a counter flow of 0.02 kg/s of water initially at . If the inner tube outside diameter is 2 cm and the overall heat transfer coefficient based on outside area is 650 , determine the required length of the exchanger. Take the specific heats of benzene and water as 1880 and 4175 J/kg‐K, respectively.(B) 2.60Correct answer is between ','. 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 A coaxial tube counter flow heat exchanger is used to cool 0.03 kg/s of benzene from 360 K to 310 K with a counter flow of 0.02 kg/s of water initially at . If the inner tube outside diameter is 2 cm and the overall heat transfer coefficient based on outside area is 650 , determine the required length of the exchanger. Take the specific heats of benzene and water as 1880 and 4175 J/kg‐K, respectively.(B) 2.60Correct answer is between ','. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of
A coaxial tube counter flow heat exchanger is used to cool 0.03 kg/s of benzene from 360 K to 310 K with a counter flow of 0.02 kg/s of water initially at . If the inner tube outside diameter is 2 cm and the overall heat transfer coefficient based on outside area is 650 , determine the required length of the exchanger. Take the specific heats of benzene and water as 1880 and 4175 J/kg‐K, respectively.(B) 2.60Correct answer is between ','. Can you explain this answer?, a detailed solution for A coaxial tube counter flow heat exchanger is used to cool 0.03 kg/s of benzene from 360 K to 310 K with a counter flow of 0.02 kg/s of water initially at . If the inner tube outside diameter is 2 cm and the overall heat transfer coefficient based on outside area is 650 , determine the required length of the exchanger. Take the specific heats of benzene and water as 1880 and 4175 J/kg‐K, respectively.(B) 2.60Correct answer is between ','. Can you explain this answer? has been provided alongside types of A coaxial tube counter flow heat exchanger is used to cool 0.03 kg/s of benzene from 360 K to 310 K with a counter flow of 0.02 kg/s of water initially at . If the inner tube outside diameter is 2 cm and the overall heat transfer coefficient based on outside area is 650 , determine the required length of the exchanger. Take the specific heats of benzene and water as 1880 and 4175 J/kg‐K, respectively.(B) 2.60Correct answer is between ','. Can you explain this answer? theory, EduRev gives you an
ample number of questions to practice A coaxial tube counter flow heat exchanger is used to cool 0.03 kg/s of benzene from 360 K to 310 K with a counter flow of 0.02 kg/s of water initially at . If the inner tube outside diameter is 2 cm and the overall heat transfer coefficient based on outside area is 650 , determine the required length of the exchanger. Take the specific heats of benzene and water as 1880 and 4175 J/kg‐K, respectively.(B) 2.60Correct answer is between ','. 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.
|
© EduRev
|
Education Revolution
|
Follow Us
|
Signup to see your scores
go up within 7 days!
Access 1000+ FREE Docs, Videos and Tests
Takes less than 10 seconds to signup