How to Use This Calculator
- Enter the current ambient temperature (the temperature of the air around you).
- Input the solar radiation value, which you can find from weather forecasts or use an average of 800 W/m² for clear sunny days.
- Specify the time of day in 12-hour format (e.g., "3 PM").
- Select the material type of the sidewalk from the dropdown menu.
- Enter the wind speed to account for cooling effects.
- Click the "Calculate" button to see the estimated sidewalk temperature.
Understanding the Results
The calculator provides an estimated temperature of the sidewalk surface based on the inputs. The formula considers:
- Solar heating of the surface
- Material properties (how well different materials absorb and retain heat)
- Wind cooling effects
Safety Guidelines
Based on the estimated temperature, here are some safety guidelines:
- If the estimated temperature is < 15°C (59°F) colder than the ambient temperature, the sidewalk may be too cold for barefoot walking.
- If the estimated temperature is > 25°C (77°F) warmer than the ambient temperature, exercise caution to prevent burns or heat-related discomfort.
- The calculator provides estimates and actual surface temperatures may vary based on specific conditions not accounted for in this model.
Principles of Heat Transfer Used
This calculator uses a simplified model of heat transfer that considers:
- Solar radiation absorption: Different materials absorb solar energy at different rates.
- Conduction: Heat transfer from the air to the surface.
- Convection: Heat loss due to wind blowing over the surface.
- Thermal mass: How quickly materials heat up and cool down (simplified in this model).