针对当前等效全装药(Equivalent Full Charge，EFC)折算系数的国家军用标准预测值与实际测试结果差距较大的问题，基于热-化学烧蚀模型，研究不同工况下射击发数与EFC射击发数间的折算系数计算方法。射击一定发数后，假设身管内壁白层厚度及成分随射击发数呈周期性变化，由质量扩散定律建立膛线起始部热-化学烧蚀量与火药燃气侵蚀性、内膛表面瞬态温度的关系。通过经典内弹道模型获得弹后空间火药燃气平均温度及内壁面强制对流换热系数，在考虑后效期高温燃气影响的基础上，建立身管内壁瞬态温度计算模型。以对内弹道过程有重要影响的射速、药量和药温为重点，计算不同射速、不同药号和不同药温下的身管内壁烧蚀量，并据此获得不同工况下的折算系数。研究发现，射速越快，装药质量越大，装药初始温度越高，单发射击造成的身管烧蚀越严重，其对应的EFC折算系数越大，其中强装药的EFC折算系数可达2。131。以某型155 mm火炮身管实弹射击数据为例，验证了新模型的合理性。
Study on the Equivalent Full Charge Conversion Coefficient of the Barrel Life Based on the Thermal-chemical Erosion Model
To explain the paradox between the experimental and theoretical results of equivalent full charge ( EFC) conversion coefficient, which can be used to convert the number of firing under various firing conditions to the number of EFC firing, a computational method of that coefficient is investigated on the basis of the thermo-chemical erosion model of the barrel. Supposing that the thickness and composition of the white layer on the inner wall of barrel change periodically after several firings, the relationship among the thermo-chemical erosion volume at the beginning of the rifling and the erosivity of the propellant and the transient temperature field of the inner layer of the barrel is established with the help of the mass diffusion law. During the firing process, the gas temperature in the space behind the projectile and the forced convection coefficient at the innerwall surface of barrel are provided by the classical interior ballistic theory. Hereafter, the model to calculate the transient temperature of the barrel can be developed. In addition, the effect of gas with relative high temperature during the after-effect period is also considered. Eventually, focusing on the firing rate, the charge mass and the charge temperature which have an essential effect on the interior ballistic process, erosion volumes under different firing rates, charge numbers and charge temperatures are calculated. Accordingly, the EFC conversion coefficients under various firing conditions are obtained. It is found that a more severe erosion of the barrel is often related to a faster firing rate, a more charge mass and a higher charge temperature. The EFC coefficient of the supercharge is up to 2. 131 . The reasonability of the proposed model is verified by using the practical firing data of a 155 mm barrel.
barrel lifeequivalent full charge conversion coefficientthermo-chemical erosiontransient temperature field
万方数据
维普
