Understanding how sunlight heats our skin is very important for health and safety. A Sun Irradiation On Human Skin CFD simulation is a computer model that shows how skin temperature changes when exposed to the sun. This type of thermal modeling of skin uses the Pennes bioheat equation to predict heat flow. Using ANSYS Fluent, we can perform a Sun Irradiation On Human Skin Fluent analysis to see how this heat can be helpful or harmful. A key part of this is the Discrete Ordinates (DO) radiation model, which calculates the sun’s energy. This study is a Sun Irradiation CFD Validation against the reference paper, “Heat Transfer Model to Predict Human Skin Temperature under Comfort Level by using Bioheat Equation” [1], to prove our computer model is accurate.

• Reference [1]: Zainol, Zaina, et al. “Heat transfer model to predict human skin temperature under comfort level by using bioheat equation.” (2019): 52-64.

Figure 1: Mathematical simplification for modeling sun irradiation on human skin [1].

Simulation Process: Fluent Setup, Transient DO Radiation for Bioheat Analysis

To begin our Sun Irradiation Fluent simulation, we modeled the different layers of human skin. We then created a simple, structured mesh with only 900 cells. Because we want to see how temperature changes over time, we set up a transient thermal analysis. The most important part of the setup was modeling the sun’s heat. We used the Discrete Ordinates (DO) radiation model in ANSYS Fluent to apply the sun’s energy directly to the surface of the skin model.

Post-processing: CFD Validation, Analyzing Skin Temperature and Solar Load

This simulation also helps us understand why we feel hot in the sun. The model shows that it takes only 10-15 minutes for the skin to reach its highest temperature in strong sunlight. Our computer model predicted a final skin temperature of 34.7°C. The reference paper [1] measured a temperature of 36.2°C. This means our result has a very small error of only 4.1%. The most important achievement of this simulation is this excellent agreement with real-world data, which proves our CFD model is a highly accurate and reliable tool that can help scientists develop better sunscreens and UV protection products to keep people safe.

The temperature contour provides a professional visual of how heat moves through the skin. This professional visual shows that the temperature on the outer surface of the skin is 32.5°C, while deeper inside, the temperature is 36.8°C. This temperature difference shows the body is working to stay cool. At the same time, the solar radiation hitting the skin is very strong, measuring between 1882.0 W/m² and 2064.5 W/m². This is like having a small heater on your skin.

Figure 2: Professional visuals showing temperature distribution from the Bioheat Equation CFD analysis and solar load from the DO Radiation Fluent Validation.