ONE CYCLE DATA COLLECTING METHOD FOR OUTPUT MEASUREMENT AND COMBUSTION ANALYSIS OF LARGE-SIZED LOW SPEED FOUR-STROKE ENGINE

摘要

To enable an accurate combustion analysis and output measurement to be attained by getting accurate one cycle data of a large-sized low speed four-stroke engine.SOLUTION: A one cycle data collecting method comprises the steps of: shutting off fuel at a preset reference cylinder, and collecting compression pressure data from the reference cylinder to make a diagram concerning a compression pressure for each of rotation angles of a crank shaft with respect to the reference cylinder; differentiating the compression pressure data with respect to the rotation angle of the crank shaft to make a diagram concerning a pressure variation rate for each of the rotation angles of the crank shaft with respect to the reference cylinder; detecting a position of a compression TDC from the diagram concerning the pressure variation rate to store a rotation angle value of the crank shaft corresponding to this position; adding the rotation angle value of the crank shaft corresponding to 0.5 cycle to the rotation angle value to determine a starting position of an intake and exhausting TDC; and collecting a combustion pressure for each of the rotation angles of the crank shaft with respect to the reference cylinder in one cycle from the starting position.SELECTED DRAWING: Figure 1