摘要: 在工业生产生活中，燃油发动机的工作原理是通过燃油进出高压油管而实现的。本文运用数学建模，通过MATLAB、SPSS、Excel、CAD等软件对数据处理，控制油管燃油进出速率改善发动机间歇性工作，实现高压油管压力控制模型。首先，在确定量燃油与恒温的状态下，通过设置单向阀每次开启关闭的时间间隔，运用波义尔定理建立模
，根据所搜集的弹性模量与压力的关系数据进行Excel拟合处理，运用压力、体积计算公式和微分方程进行求解计算，最后利用MATLAB进行求解编程，得出管内外压力都控制在100 MPa左右时，
；再假设油管内部压力分别在
、5 s、10 s内从100 MPa调整到150 MPa并趋于稳定时，
、5.7862 ms和5.7838 ms。然后，通过控制内部压力的凸轮角速度，由角速度计算公式
，由于
和
未知，先对查找的有关针阀运动曲线数据进行SPSS分析，做出针阀运动曲线，再用CAD软件做出凸轮运动示意图，结合Excel处理凸轮边缘曲线数据，运用参变分离的常微分思想做出极角与极轴拟合关系图形，分析图形、数据再结合质量守恒定律得出
和
的值，进而计算出角速度
。最后，再增加一个喷油嘴的前提下，建立高压双轨道燃油喷射模型，运用MATLAB软件分析所选择的指标作出双针阀运转策略图像，分析图像得出喷油嘴B、C交替开启，并取时间间隔为50 ms，高压油泵凸轮旋转角速度设置为0.0993 rad/ms；再增加一个单向减压阀门，判别公式
，计算减压阀开启时初始压强范围，并得出减压阀需要在喷油嘴关闭时开启，高压油泵凸轮角速度
。再将设计的高压双轨燃油喷射模型与数据库进行对比，验证算法的实用性。
Abstract:
In industrial production, the basic working principles of fuel engines are realized by fuel entering and ejecting high-pressure fuel pipes. In this paper, use the idea of mathematical modeling, through the use of MATLAB, SPSS, Excel, CAD and other software for intuitive data analysis, and then improve the fuel entry and ejection rate of the high-pressure fuel pipe to improve the intermittent operation of the engine and realize the pressure control model of the high-pressure fuel pipe. In the first place, under the condition of a certain amount of fuel and constant temperature, by setting the time interval for each opening and closing of the one-way valve, use Boyle’s theorem to establish a model:
, and fit according to the collected data of the relationship between elastic modulus and pressure by Excel Processing, use the pressure, volume calculation formula and differential equation to solve the calculation, and finally use MATLAB to solve programming: when the pressure inside and outside the tube is controlled at about 100 MPA,
; when the internal pressure of the tubing is adjusted from 100 MPa to 150 MPa within 2 s, 5 s, and 10 s, and becomes stable,
, 5.7862 ms and 5.7838 ms. After that, by controlling the cam angular velocity of the internal pressure, the angular velocity calculation formula:
, and
,
are unknown, first analyzing by SPSS the searched needle valve movement curve data, make the needle valve movement curve, and then use the CAD software to make the cam movement schematic diagram. By the Excel processing of cam edge curve data, use the idea of parametric separation of ordinary differentials to make a graph of the fitting relationship between polar angle and polar axis, analyze the graph and data and combining the law of conservation of mass to obtain the value of
,
. And then calculate the angular velocity:
. In the end, under the premise of adding another fuel injector, readjust the fuel supply and fuel injection strategy, establish a high-pressure dual-track fuel injection model, using MATLAB software to process and analyze the selected indicators to make a data image, and analyze the image to draw a conclusion: Oil nozzles B and C are opened alternately, and the time interval is 50 ms, the rotation angular velocity of the high-pressure oil pump cam: 0.0993 rad/ms; if a one-way pressure reducing valve is added, according to the discriminant formula:
, the initial pressure range when the pressure reducing valve is opened is calculated. And it is concluded that the pressure reducing valve needs to be opened at the time when each injector is closed, and the high-pressure oil pump is set to control the angular velocity of the cam:
. At the same time, the designed high pressure dual-track fuel injection model is compared with the database to verify the practicability of the algorithm.