A Three-Layers Plane Wall Exposed to Oscillating Temperatures with Different Amplitudes and Frequencies

A linear model of three layers plane wall exposed to oscillating temperatures with different amplitudes and frequencies was built by using a physical superposition. A physical superposition of two states was performed, one state is a wall which one surface is exposed to oscillating temperature and the other surface is exposed to zero relative temperature and a second state is a wall which one surface is exposed to relative zero temperature while the other surface is exposed to oscillating temperature with different amplitudes and frequencies. Temperature distributions were introduced for different amplitudes, frequencies and thermal conductivities. It was shown that increasing the frequency value decreases the temperature penetration length, high frequency value leads to extremum temperature values changes on the surface while low frequency value allows gradually temperature changes during the time period. Temperature distribution lines where there are at the same time heat flux entry and heat flux exit were not received for the same constraint frequencies.