1. Thin steel plates are subjected to a steady stream of air flowing along their surface at 2 m/s. The plates are held at 40 deg C while the air temperature outside the BL is 90 deg C. The plates are 1 m long in direction of the air flow, and 2 m across (= width). Estimate the average convection coefficient for the entire plates as well as the heat transfer rate. The relevant air properties at around the film temperature are: 1.038 kg/m3; 1009 J/(kg-K); 2.042E-05 Pa-s; 0.0293 W/(m-K). 2. Air is flowing through a 20 m long pipe of 20 cm diameter at a rate of 0.5 kg/s. The inlet air temperature is 40 deg C; the entire pipe wall is held at a constant temperature of 90 deg C. Estimate the air temperature at the outlet as well as the heat transfer rate for the entire length of the pipe. Use the air properties as given in Q 1. Heat transfer. Solve no.2 please.

1. Thin steel plates are subjected to a steady stream of air flowing along their surface at 2 m/s. The plates are held at 40 deg C while the air temperature outside the BL is 90 deg C. The plates are 1 m long in direction of the air flow, and 2 m across (= width). Estimate the average convection coefficient for the entire plates as well as the heat transfer rate. The relevant air properties at around the film temperature are: 1.038 kg/m3; 1009 J/(kg-K); 2.042E-05 Pa-s; 0.0293 W/(m-K). 2. Air is flowing through a 20 m long pipe of 20 cm diameter at a rate of 0.5 kg/s. The inlet air temperature is 40 deg C; the entire pipe wall is held at a constant temperature of 90 deg C. Estimate the air temperature at the outlet as well as the heat transfer rate for the entire length of the pipe. Use the air properties as given in Q 1. Heat transfer. Solve no.2 please.

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 6.54P

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