Understanding Of Driverless Visual Scene Based On Deep Learning

Diesel engines are widely used in automobile,ship and aviation because of their good economy,low fuel consumption and high reliability.Because the global petroleum resources are decreasing,exhaust gas turbocharging technology is widely used in fuel engines with its advantages of high performance,low fuel consumption and low emissions.Compressor is the key component of turbocharger.Before the advent of computational fluid dynamics(CFD)technology,the main way to design a new type of compressor and obtain flow characteristics was through experiments,but this method was not only time-consuming and costly,but also often affected by environment factors.CFD is gradually accepted by scholars because of its low cost and fast speed.Therefore,CFD is used to explore the flow characteristics and internal flow of compressor.The main study work and major achievements are as follows:1.State the research condition of turbocharger compressor at home and abroad;introduce the background,methods and main contents of the article briefly introduced.The composition,classification and working principle of turbocharger compressor are briefly introduced.2.According to the SOFIM8140 engine,the compressor is designed.The compressor impeller adopts a half-open impeller with forward-tilt and backward-bend.The inlet and outlet diameter of the impeller are 38mm and 52 mm respectively.Compressor diffuser adopts vaneless diffuser with an external diameter of 80 mm.Compressor volute adopts variable cross-section volute with an outlet area of 9.2 cm~2.3.A model of the compressor is created by Solidworks software,and the internal flow of the compressor is extracted by using Boolean operation.In order to facilitate numerical simulation,the internal flow is optimized.The internal flow is divided into unstructured grids by ICEM software.The quality of grids is good,and the number of grids is about480,000.4.The compressor is simulated by ANSYS FLUENT software.Using standard k-?turbulence model and mass flow inlet and pressure outlet as boundary conditions,flow characteristics charts are calculated.The study shows that:1)when the rotational speed is fixed,the pressure ratio decreases when the flow rate increases and the efficiency increases first and then decreases with the increase of flow rate,which reaches the maximum value at a certain flow point;2)when the rotational speed increases,the pressure ratio increases,and the maximum efficiency point moves towards the direction of large flow rate.But at different rotational speeds.The maximum efficiency has little change.5.The internal flow of compressor at different operating points is compared and analyzed.The study shows that:1)at the same speed,when the flow rate increases,the pressure difference between suction surface and pressure surface of blade will gradually increase,and the possibility of gap leakage will increase;2)Flow loss will occur at impeller inlet,blade tail,diffuser inlet and volute tongue,which will affect compressor efficiency.3)When the compressor speed increases,pressure ratio and airflow speed both show an upward trend;4)Because of the gap leakage,when the speed is high,the working flow range of the compressor will be reduced.6.Choosing a matching exhaust bypass valve for compressor,which can make the service life of compressor longer...