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• The guide vane is added to the air inlet chamber of the intercooler. • An end-to-end model of the intercooler guide vane based on PSO-SVR algorithm. • Structure parameters of guide vane are optimized using genetic algorithm. In order to fundamentally solve the problem of poor air flow uniformity in the cooling pipe of the heavy-duty vehicle intercooler, which leads to poor heat exchange effect, this paper innovatively proposes to add a guide vane in the air chamber of the intercooler. The air flow uniformity in the cooling pipe of the heavy-duty vehicle intercooler is investigated under different structural parameters of guide vane based on the established end-to-end model. In fact, the end-to-end prediction model is innovatively proposed to characterize the relationship between the structural parameters of guide vane and performance parameters without conducting the high-cost and long-term experiments or numerical simulation. Besides, structure parameters of guide vane with the optimal airflow uniformity coefficient are obtained using genetic algorithm (GA), that is, the diversion angle (α) is 18°, the width of rectangular holes in the guide vane (L) is 6 mm and the number of rectangular holes in the guide vane (N) is 3. To demonstrate the effectiveness of the proposed method, the optimized intercooler is validated and it is found that the airflow uniformity coefficient of the optimized intercooler is 0.983, which is 5.25% higher than the original structure, the outlet temperature is reduced by 8.2 °C. [ABSTRACT FROM AUTHOR]

• Direct numerical simulation of droplet evaporation without any empirical parameter. • Identification of a sharp layer of interface cells for occurrence of phase change. • Algebraic compressive differencing scheme to maintain high resolution of interface. • Satisfactory prediction of droplet evaporation for a wide range of cases. • Sessile droplets gain averagely 29 percent of heat for evaporation from ambient gas. This study presents a sharp-interface algebraic volume-of-fluid (SA-VOF) approach towards direct numerical simulation of evaporating droplets in a finite-volume framework. An interface identification scheme is introduced to determine a sharp layer of interface cells where liquid-vapor phase change occurs. The rate of vaporization is directly computed from the local gradient of the vapor mass fraction at the interface without any tuning parameter in the evaporation model. In addition, a modified compressive differencing scheme is employed to maintain high resolution of the interface. A solver based on the SA-VOF approach is developed and validated by several case studies including the Stefan problem for evaporation in one dimension, evaporation of sessile droplets in the constant contact angle mode, and evaporation of droplets suspended in a flowing air stream. Comparisons between numerical predictions and either analytical solutions or experimental data show that the SA-VOF approach not only computes the evaporation rate with high accuracy but also ensures highly resolved liquid-vapor interface. The solver demonstrates the capability in revealing minute details of the complex characteristics associated with droplet evaporation. [ABSTRACT FROM AUTHOR]