Wa 18 Air Preheater Wa 17 t go 叶 + emin toc tgo emax t gc Twa t17 t18 Wa 18 Air Preheater Wo 100 Assuming the size of tube - 1 oc Two Design of Air Preheater t17 AP = 5.55 x 10-8 G² page 332 AP = 2.54 to 5.08 cm H₂O page 447 Use AP = 5 cm H₂O AP = 1.9685 in H₂O = 5955.54694 kg/m² - hr 1747.768014 NE (D) (H) T (0.0422 ) ( 3.75) NE = 3515.525 Say N₁ = 3516 tubes theoretical number of tubes Note: Assume the actual number of tubes so that there will be uniform spacing G = 5.55 x 10- @max G= 1.654 kg/m²-s to Over-all Coefficient of Heat Transfer, U U = A + BG No 59 For Smooth Tube Economizers No = 60 Size A = 1.95 page 330 Do Outside diameter 0.0422 B 0.00045 Di Inside diameter 0.0351 m Thickness 0.00355 m U = 1.95 + 0.00455955.55) Logarithmic Mean Temperature Difference U = 4.6300 tgc = 423.47 °C Omax = tab ta Qair preheater 3611 kJ/s from 3rd Checking E in Tabulation Ntactual tgD = 416.43 °C t17= 40°C = 416.43 - 32 384.43 °C Qair preheater 3106992.321 kcal/hr Q U ( A ) ( LMTD) Nta (Ntb) = 60 (59) Ntactual = 3540 Length Nta = tubes actual 60 tubes +18= 32 °C toc 423.47 - 40 A = 3106992.321 4.6300 (383.9509668) 1747.768014 m² = Area of Heating Surface L = 383.47 °C = Width Ntb= 59 Nea (Do) + (Nta + 1 ) S 60 (0.0422) + ( 60 + 1) (0.025) tubes LMTD @max In 8min max 384.43- 383.47 LMTD = In 384.43 383.47 LMTD =383.9509668 °C Assume Number of Tubes A = (D₂) (H) (N₂) H = 3.75 m S 0.025 m W = W W 4.057 m Ntb (Do) + (Nth + 1) S 59 (0.0422) + ( 59+ 1 ) (0.025) 3.9898 m Note: value from square root of N₁
Wa 18 Air Preheater Wa 17 t go 叶 + emin toc tgo emax t gc Twa t17 t18 Wa 18 Air Preheater Wo 100 Assuming the size of tube - 1 oc Two Design of Air Preheater t17 AP = 5.55 x 10-8 G² page 332 AP = 2.54 to 5.08 cm H₂O page 447 Use AP = 5 cm H₂O AP = 1.9685 in H₂O = 5955.54694 kg/m² - hr 1747.768014 NE (D) (H) T (0.0422 ) ( 3.75) NE = 3515.525 Say N₁ = 3516 tubes theoretical number of tubes Note: Assume the actual number of tubes so that there will be uniform spacing G = 5.55 x 10- @max G= 1.654 kg/m²-s to Over-all Coefficient of Heat Transfer, U U = A + BG No 59 For Smooth Tube Economizers No = 60 Size A = 1.95 page 330 Do Outside diameter 0.0422 B 0.00045 Di Inside diameter 0.0351 m Thickness 0.00355 m U = 1.95 + 0.00455955.55) Logarithmic Mean Temperature Difference U = 4.6300 tgc = 423.47 °C Omax = tab ta Qair preheater 3611 kJ/s from 3rd Checking E in Tabulation Ntactual tgD = 416.43 °C t17= 40°C = 416.43 - 32 384.43 °C Qair preheater 3106992.321 kcal/hr Q U ( A ) ( LMTD) Nta (Ntb) = 60 (59) Ntactual = 3540 Length Nta = tubes actual 60 tubes +18= 32 °C toc 423.47 - 40 A = 3106992.321 4.6300 (383.9509668) 1747.768014 m² = Area of Heating Surface L = 383.47 °C = Width Ntb= 59 Nea (Do) + (Nta + 1 ) S 60 (0.0422) + ( 60 + 1) (0.025) tubes LMTD @max In 8min max 384.43- 383.47 LMTD = In 384.43 383.47 LMTD =383.9509668 °C Assume Number of Tubes A = (D₂) (H) (N₂) H = 3.75 m S 0.025 m W = W W 4.057 m Ntb (Do) + (Nth + 1) S 59 (0.0422) + ( 59+ 1 ) (0.025) 3.9898 m Note: value from square root of N₁
Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)
8th Edition
ISBN:9781305387102
Author:Kreith, Frank; Manglik, Raj M.
Publisher:Kreith, Frank; Manglik, Raj M.
Chapter6: Forced Convection Over Exterior Surfaces
Section: Chapter Questions
Problem 6.52P
Related questions
Question
what is an air preheater, what are formulas, and their importance, define the diagram, and give me a script on how to explain the design of an air preheater, and how did values end up in that number. based on standards
Expert Solution
This question has been solved!
Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.
Step by step
Solved in 2 steps with 8 images
Recommended textbooks for you
Principles of Heat Transfer (Activate Learning wi…
Mechanical Engineering
ISBN:
9781305387102
Author:
Kreith, Frank; Manglik, Raj M.
Publisher:
Cengage Learning
Principles of Heat Transfer (Activate Learning wi…
Mechanical Engineering
ISBN:
9781305387102
Author:
Kreith, Frank; Manglik, Raj M.
Publisher:
Cengage Learning