Investigation of the total thermal resistance of children’s bedding systems at various air temperatures and velocities using CFD analysis

The total thermal resistance of bedding systems can be affected by environmental variables. A computational fluid dynamics (CFD) model of child manikin and duvet bedding system was developed to investigate the effects of air temperature (T_air, 5–25°C) and air velocity (V_air, 0.2–1.0 m/s) on the total thermal resistance (R_t) of children’s bedding systems composed of duvet with different total filling weights (w, 350–1000 g) in three sleep postures (P1, P2, and P3). Heat flux experiments were conducted to validate the CFD model. Results from the simulations indicated that a 1°C rise in T_air led to a reduction in R_t by 0.09–0.11 clo. Furthermore, R_t decreases with the increase in V_air, and the reduction in R_t slows down as V_air increases. Variations in T_air and V_air had the most significant impact on R_t in the P2 sleep position and the least effect in the P3 sleep position. Based on the simulation results, a prediction equation for the R_t of the children’s bedding systems was established. These research findings offer valuable insights into the scientific selection and design of children’s bedding systems, which are crucial for improving children’s sleep quality.