The charging efficiency of two-stroke cycle diesel engines can be estimated from measurement of the concentration of 0, and CO, in the burned gases within the cylinder, or in the exhaust blow down...

The charging efficiency of two-stroke cycle diesel engines can be estimated from measurement of the concentration of 0, and CO, in the burned gases within the cylinder, or in the exhaust blow down pulse prior to any mixing with fresh air. The engine bore = 125 mm, stroke = 150 mm, compression ratio = 15. The fuel flow rate at 1800 revlmin is 1.6 g/s per cylinder. The conditions used to evaluate the air density for the reference mass are 300 K and 1 atm. The molar concentrations (dry) of CO, and 0, in the in-cylinder burned gases are 7.2 and 10.4 percent (see Fig. 4-22). The scavenging air flow rate is 80 g/s. Evaluate (a) the charging efficiency, (b) the delivery ratio, and (c) the trapping efficiency (assuming the trapped mass equals the reference mass).