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Abstract

Vehicle dynamism is one of the most important operational features of a vehicle. T he speed of transportation, timeliness of the tasks of delivery of goods to the destination, the total volume of transportations per unit of time depend on i ts characteristics. The rational use of the engine power reserve allows provid ing the highest level of dynamics and effective acceleration of the vehicle . The work s of many authors are dedicated to the development and construction of a rational dynamic car overclocking characteristic, as it enables high dynamic performance of the car. Aerodynamic impedance of the motor is the factor that has the greatest impact on the energy consumption of the engine of the car. Therefore, taking into account the aerodynamic force arising from the movement of the car is an important component in the evaluation of the dynamic and energy parameters of the cars. The current method of calculating the aerodynamic drag force of a car was proposed at the beginning of the last century. According to the proposed theory, the aerodynamic drag force is determined by using the aerodynamic drag coefficient , which depends on the shape of the body and varies with the speed of movement. However, in the future, the mentioned coefficient was assumed to be equal to a constant value, which in turn introduced a significant error in the assessment of the dynamic and energy performance indicators of the car. In this article, the method of determining the aerodynamic force acting on a car in the course of motion is considered, which is based on the empirical dependence of the coefficient of frontal aerodynamic resistance on the speed of movement of the car. An improved technique for determining the rational dynamic characteristics of cars using these parameters is proposed. The dynamic characteristics of the “ SHRE K” armored vehicle in the range of speeds from 0 m/s to 30 m/s and acceleration from 0 m/s 2 to 2 m/s 2 are shown in the graphical form in accordance with the developed methodology for taking into account the refined parameters of calculation of the aerodynamic resistance force, which acts on the car while driving at different speeds. The results of synthesis of rational dynamic characteristics of car acceleration are presented in the article, taking into account the dependence of the coefficient on speed.