Heat Transfer Rate (\( Q_k \)):

\[ Q_k = \frac{k \cdot A \cdot (T_o - T_i)}{x} \]

Where:

• \( Q_k \) is the heat transfer rate, in watts (W).
• \( k \) is the thermal conductivity, in watts per kelvin-meter (W/°K-m).
• \( A \) is the surface area, in square meters (m²).
• \( T_o \) is the outside wall temperature, in kelvin (°K).
• \( T_i \) is the inside wall temperature, in kelvin (°K).
• \( x \) is the wall thickness, in meters (m).