Enhanced heat transfer and flow resistance characteristics of high temperature flow regulating valves with Tesla cooling structure

Cooling channels are typically integrated into high temperature flow regulating valves to mitigate the adverse effects of elevated temperatures on the operation of digital valves and embedded sensors. However, conventional straight cooling channels often suffer from inefficient heat dissipation and excessive pressure losses. In this study, a novel high temperature flow regulating valve incorporating 12 Tesla cooling channels is proposed to simultaneously optimize heat transfer enhancement and flow resistance reduction. Three-dimensional steady-state numerical simulations, based on the Navier-Stokes equations (Laminar flow model), were conducted to analyze the pressure, temperature, Colburn factor (j), and friction factor (f). The Colburn factor (j) was determined from the relationship between heat absorption, surface temperature difference, heat transfer area, and mass velocity of the fluid, while the friction factor (f) was derived from the correlation between the inlet-outlet pressure difference, hydraulic diameter, and mass velocity of the fluid. Numerical results reveal that the mixed cooling capacity of the Tesla structure improves with increasing inlet pressure. Among the 12 schemes, Scheme 1 exhibited the highest heat transfer enhancement with the maximum Colburn factor (j) of 0.173, while Scheme 5 demonstrated the best flow performance with the lowest friction factor (f) of 1.357. Experimental validation confirmed close agreement between the experimental data and numerical results, with discrepancies within 8.83% for j and 6.39% for f. Through analysis of the JF impactor factor, which evaluates the combined performance of heat transfer and flow, the high temperature flow regulating valve with Scheme 11 Tesla cooling channels achieved optimal overall performance, enhancing heat transfer capacity by up to 28.7% and reducing maximum pressure losses by 17.9%. This study provides valuable insight for the design of the valve, enhancing their thermal management and operational efficiency.