(5.6)f=1-Y(1+y)(1+a+8)(f₁ + a£ + Cot2Lp We wish to use the analytical model developed by Joshi and Webb to predict the heattransfer and friction characteristics (j and f) of the Offset Strip-Fin (OSF) array.1.Compare the predictions of the friction factor using equation 5.6 of the bookto the measurements of Webb and Joshi (taken from "Prediction of theFriction Factor for the Offset Strip-Fin Matrix" and given in the last columnof the table below) for surfaces 1 and 8 (see Table below) at Reph = 529 and623, respectively. As shown in the table below, the experimental frictionfactors for surfaces, 1 and 8 are 0.0551 and 0.0434 respectively. Use CD =0.8.Surface18α0.1230.224t/l0.0160.064h (mm)38.138.1t (mm) Dh (mm)7.5180.4061.626 10.8970.05510.04342. Use the Webb and Joshi model given in the notes to make a plot of Nu versusthe fin length (1) for 1 mm < 1<5 mm. You should use 0.5 mm incrementsof 1 or smaller. Use α= 0.184, t = 0.102 mm, h = 4.98 mm, and Reph = 500.Explain why the Nu behaves as it does with respect to 1. Assume that the finefficiency is equal to 1.3. Convert the Nu data that you generated in Problem 2 above into j-factors byassuming that Pr = 0.7. Next calculate the friction factor for the samevalues of 1, the same Reph, and for the same geometric parameters as Problem2. Plot flj versus the fin length (1) for 1 mm <5 mm. Does your plotverify the Reynolds analogy for this case? Explain why this should beexpected.

We wish to use the analytical model developed by Joshi and Webb to predict the heat transfer and friction characteristics (j and f) of the Offset Strip-Fin (OSF) array. 1. Compare the predictions of the friction factor using equation 5.6 of the book to the measurements of Webb and Joshi (taken from "Prediction of the Friction Factor for the Offset Strip-Fin Matrix" and given in the last column of the table below) for surfaces 1 and 8 (see Table below) at Reph = 529 and 623, respectively. As shown in the table below, the experimental friction factors for surfaces, 1 and 8 are 0.0551 and 0.0434 respectively. Use CD = 0.8. Surface 1 8 α 0.123 0.224 t/l 0.016 0.064 h (mm) t (mm) D₁ (mm) 38.1 0.406 7.518 1.626 10.897 38.1 f 0.0551 0.0434 2. Use the Webb and Joshi model given in the notes to make a plot of Nu versus the fin length (1) for 1 mm <5 mm. You should use 0.5 mm increments of 1 or smaller. Use a= 0.184, t = 0.102 mm, h = 4.98 mm, and Reph = 500. Explain why the Nu behaves as it does with respect to 1. Assume that the fin efficiency is equal to 1.

We wish to use the analytical model developed by Joshi and Webb to predict the heat transfer and friction characteristics (j and f) of the Offset Strip-Fin (OSF) array. 1. Compare the predictions of the friction factor using equation 5.6 of the book to the measurements of Webb and Joshi (taken from "Prediction of the Friction Factor for the Offset Strip-Fin Matrix" and given in the last column of the table below) for surfaces 1 and 8 (see Table below) at Reph = 529 and 623, respectively. As shown in the table below, the experimental friction factors for surfaces, 1 and 8 are 0.0551 and 0.0434 respectively. Use CD = 0.8. Surface 1 8 α 0.123 0.224 t/l 0.016 0.064 h (mm) t (mm) D₁ (mm) 38.1 0.406 7.518 1.626 10.897 38.1 f 0.0551 0.0434 2. Use the Webb and Joshi model given in the notes to make a plot of Nu versus the fin length (1) for 1 mm <5 mm. You should use 0.5 mm increments of 1 or smaller. Use a= 0.184, t = 0.102 mm, h = 4.98 mm, and Reph = 500. Explain why the Nu behaves as it does with respect to 1. Assume that the fin efficiency is equal to 1.

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.

Chapter3: Transient Heat Conduction

Section: Chapter Questions

Problem 3.9P: 3.9 The heat transfer coefficients for the flow of 26.6°C air over a sphere of 1.25 cm in diameter...

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We wish to use the analytical model developed by Joshi and Webb to predict the heat transfer and friction characteristics (j and f) of the Offset Strip-Fin (OSF) array. Surface 1 8 α 0.123 0.224 0.016 0.064 h (mm) 38.1 38.1 t (mm) Dh (mm) 0.406 7.518 1.626 10.897 0.0551 0.0434 2. Use the Webb and Joshi model given in the notes to make a plot of Nu versus the fin length (1) for 1 mm < 1<5 mm. You should use 0.5 mm increments of 1 or smaller. Use α= 0.184, t = 0.102 mm, h = 4.98 mm, and Reph = 500. Explain why the Nu behaves as it does with respect to 1. Assume that the fin efficiency is equal to 1. 3. Convert the Nu data that you generated in Problem 2 above into j-factors by assuming that Pr = 0.7. Next calculate the friction factor for the same values of 1, the same Reph, and for the same geometric parameters as Problem 2. Plot flj versus the fin length (1) for 1 mm
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