As a result of establishment of good shape of the combustion chamber by making the piston stroke longer than that applied to conventional engines and high-pressure injection of fuel, low fuel consumption is secured. The measures for burning of low grade fuel oil is also established.
2.5 Compactness and Reduction of Specific Weight
By raising the power ratio, weight per output is reduced and as a result it is improved to facilitate effective utilization of the engine room compared with engine of the same output.
3. OUTLINE AND PRINCIPAL PARTICULARS
Fig.1, 2, 3 show engine outline of DK-20, DK-26 and DK-28. Fig.4, 5, 6 show cross section of DK-20, DK-26 and DK-28. The DK-20 and DK-28 are currently manufactured in 6 and 8 cylinders in-line and in April this year DK-20 with 5 cylinders in-line has been newly added to DK series engine. Furthermore, the DK-26 with 6 cylinders in-line will be delivered to markets in September this year. The new DK series engines are aimed at the auxiliary power, marine propulsion and co-generation markets.
Table 1 show principal particulars of DK-20, DK-26 and DK-28. The DK-20 hasa bore of 200 mm, a stroke of 300 mm and a stroke / bore ratio of 1.5. The DK-26 has a bore of 260 mm, a stroke of 380 mm and a stroke / bore ratio of 1.46. The DK-28 has a bore of 280 mm, a stroke of 390 mm and a stroke/bore ratio of 1.39. These stroke / bore ratio are bigger than those of conventional DL type same bore size engine and therefore it makes to be able to get the suitable shape of combustion chamber and high compression ratio. The maximum firing pressure is 16 MPa but the design pressure is suitable fore 20 MPa. The maximum firing
