Thermal Conductivites between two dissimilar metals

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Schematic of two stacked blocks against a vertical wall: a thin layer labelled X on top and a thicker block labelled Y below, with dimensions d1 and d2 marked on the right, and a large arrow labelled Heat Source (Uniform across area) pointing at the layers.

1. Homework Statement

I've been failing to find examples dealing with "longitudinal" thermal conductivity and how two objects in contact with each other would affect the heat flow compared to not being in contact at all.

Problem: Given the following information, determine the thermal energy at 1 meter from the heat source for material X for the two cases 1) Where material X is not contact with material Y 2) Where material X and Y are in contact as shown. For both cases, first assume materials are in vacuum, then assume there are in ambient air at STP (273 K).

Homework Equations


Thermal Conductivity
X: 2,000 W/(m K)
Y: 50 W/(m K)

d1 = 0.00001 m
d2 = 1 m

Heat Source
q = 100 W

Heat Transfer Coefficient
Air: 10 W/(m^2 K)

The Attempt at a Solution


What I am struggling with is whether the conduction between X and Y would essentially "shorten" the conduction of material X itself. I am also unsure if thermal radiation would come into play. Any help is appreciated!
 
Lets Get Physical said:
whether the conduction between X and Y would essentially "shorten" the conduction of material X itself.
"Series resistance" versus "parallel?"