Design of ignition and fuel systems for two-stroke engines: A statistical experimental design approach

Abstract

Abstract Two problems in the production of two-stroke outboard marine engines, namely the low speed problem at wide open throttle and the pickup stall problem, are solved using a statistical experimental design approach. Because theoretical relationships between the controllable variables and the performance of the engine are difficult to establish, it is unrealistic to solve these problems analytically from a thermodynamic approach. Experimental design has been proved to be an effective and efficient methodology for solving the problems in this situation. In this project, four experiments were conducted sequentially, and more than 200 readings were taken. It is required to optimize the setting of the different parameters so that the engine can reach a sufficiently high speed at wide open throttle and the vibration is reduced to an acceptably low level. Analysis of the experimental results suggests optimal choices of spark plug, advance firing angle, pressure relief hole size, spark plug gap, fuel flow rate, and rate of change of fuel flow rate.