Answered: Determine conductive resistance (in…

Engineering

Mechanical Engineering

Determine conductive resistance (in K/W) of a 80 m^2 plane wall composed of 2 layers:

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.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.37P: 1.37 Mild steel nails were driven through a solid wood wall consisting of two layers, each 2.5-cm...

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Concept explainers

Conduction and Convection

When energy travels from one object to another it is said to have undergone heat transfer. Heat transfer is nothing but the transfer of thermal energy or internal energy from one thing to another, like e.g., when a vessel with water, kept on top of a burner, heats up because of the flame underneath it.

Question

Determine conductive resistance (in K/W) of a 80 m^2 plane wall composed of 2 layers:

Layer 1: brick, thickness δ1 = 620 mm, thermal conductivity λ1 = 0.310 W/(m.K)

Layer 2: EPS, thickness δ2 = 52 mm, thermal conductivity λ2 = 0.026 W/(m.K)

Evaluate the heat loss through this wall if indoor temperature is 22 C and outdoor temperature is -18 C.

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