HVOF coatings generally have a high bonding strength and good compactness, which improve the wear, corrosion, high-temperature oxidation, and fatigue properties of the substrate. They are widely used in automobile, home appliance, petrochemical, aerospace, and other fields. The flame flow characteristics and particle in-flight behaviors during the spray process have an essential influence on the coating microstructure and, thus, properties. This paper deals with a flow field model of a HVOF process that uses kerosene as fuel. A one-step chemical reaction model and the eddy dissipation model were used to numerically calculate the flame dynamics. The numerical simulations predicted the variation laws of flame pressure, temperature, velocity, Mach number, and combustion components. On this basis, the temperature, velocity, and trajectory of WC-12Co particles were calculated using a Lagrangian approach. The effect of the oxygen/fuel ratio on the flame flow and particles characteristics was analyzed, as well as the effect of particle diameter, shape, injection angle, and nitrogen flow rate on particle in-flight processing.

HVOF涂层通常具有较高的粘合强度和良好的致密性，可改善基材的磨损，腐蚀，高温氧化和疲劳性能。它们被广泛应用于汽车，家用电器，石油化工，航空航天等领域。喷涂过程中的火焰流动特性和飞行过程中的颗粒行为对涂层的微观结构和性能都有重要影响。本文研究了以煤油为燃料的HVOF过程的流场模型。使用一步化学反应模型和涡流消散模型对火焰动力学进行数值计算。数值模拟预测了火焰压力，温度，速度，马赫数和燃烧成分的变化规律。在此基础上，温度，速度，使用拉格朗日方法计算WC-12Co颗粒的运动轨迹。分析了氧/燃料比对火焰流动和颗粒特性的影响，以及颗粒直径，形状，喷射角度和氮气流速对颗粒飞行过程的影响。