A New Approach to Sensible Heat Flux via CFD-Surface Renewal Integration

This study integrates surface renewal theory (SR) with computational fluid dynamics (CFD) models to explore the estimation of sensible heat flux in tea plantations. SR describes the turbulent transport processes at the air–water interface and has been widely applied in sensible heat flux estimation. However, its practical application faces challenges, such as determining the calibration coefficient (α) and the reliability of high-frequency temperature sensors (10 hz). This research addresses these issues by combining large eddy simulation (LES) models with CFD simulations to simulate high-frequency temperature variations in flat tea plantation fields. The results indicate that the LES model accurately simulates temperature fluctuations across different timescales (1 min, 30 min), with R2 values ranging from 0.72 to 0.99, suggesting its suitability for precise sensible heat flux calculations. Furthermore, a new method for determining the calibration coefficient α using CFD simulations is proposed, which accounts for variations in atmospheric stability and terrain, thus improving the accuracy and applicability of SR in heterogeneous environments. The findings demonstrate that the CFD-based approach offers a cost-effective alternative to traditional eddy covariance systems, simplifying field measurements and enhancing the precision of sensible heat flux calculations under various atmospheric conditions (sunny, cloudy, overcast, nighttime), thereby broadening the potential applications of surface renewal theory in crop water requirement research.