JP2008189103A - Low fuel consumption main engine mounted vessel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a low fuel consumption main engine mounted vessel mounted with main engines of derating specifications having outputs equivalent to a normal specification and suppressed in increases of the length of an engine room and hull resistance. <P>SOLUTION: In this vessel, a plurality of two-stroke diesel main engines of the derating specifications are mounted, and propellers of the same number as that of the main engines are provided at the stern. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention relates to a low fuel consumption main engine-equipped ship.

In a two-stroke diesel main engine mounted on a large vessel, the maximum pressure is the same as the normal specification, the average effective pressure is reduced from the normal specification, the output is reduced from the normal specification, and the fuel consumption is lower than the normal specification. It is possible to design a derating specification with reduced noise.

Since the main engine of the derating specification has a smaller output than the main engine of the normal specification, when the main engine of the derating specification is installed, in order to obtain the same output as the main engine of the normal specification, It is necessary to increase the number of cylinders compared to the main engine, or to increase the cylinder diameter compared to the normal engine. When the number of cylinders is increased, the engine room length increases and the cargo compartment length and thus the cargo volume decreases, and when the cylinder diameter is increased, the width of the main engine increases, the stern becomes thicker and the hull resistance increases.
The present invention has been made in view of the above-mentioned problems, and is equipped with a fuel-efficient main engine equipped with a derating specification main engine having an output equivalent to that of a normal specification, and an increase in engine room length and hull resistance are suppressed. The purpose is to provide a ship.

In order to solve the above problems, the present invention provides a low fuel consumption main engine-equipped ship equipped with a plurality of derating specification two-stroke diesel main engines and having the same number of propellers on the stern as the main engines. To do.
By installing multiple derating 2-stroke diesel main engines, the output is equivalent to that of the normal engine, and the increase in the number of cylinders per main engine is suppressed, thereby suppressing the increase in engine room length. be able to. By suppressing the increase in hull resistance by approximating the stern shape in the vicinity of the propeller, which is arranged in the same number as the main engine, to the stern shape in the vicinity of the propeller of a 1-axle ship equipped with a normal main engine it can. By installing multiple derating specification 2-stroke diesel main engines, the increase in cylinder diameter is suppressed and the increase in width of each main engine is suppressed, so that the stern near each propeller is suppressed from becoming thick, Increase in hull resistance is suppressed.

According to the present invention, there is provided a low fuel consumption main engine-equipped ship equipped with a derating specification main engine having an output equivalent to that of a normal specification, and an increase in engine room length and hull resistance are suppressed.

A fuel efficient main engine-equipped ship according to an embodiment of the present invention will be described.
Assuming the case where B &W's S80MC-C main engine, a typical marine 2-stroke diesel main engine, is mounted on a 300,000 ton VLCC, the present invention is applied Compare with the VLCC.
The specifications of B &W's S80MC-C main engine are shown in FIG. FIG. 2 (a) shows a VLCC equipped with a main engine having a normal specification, and FIG. 2 (b) shows a VLCC to which the present invention is applied.
The VLCC shown in FIG. 2 (a) is a one-machine single-shaft ship equipped with one seven-cylinder normal specification S80MC-C main engine 1 and one propeller 2.
The VLCC shown in FIG. 2 (b) is a two-machine two-shaft ship equipped with two S80MC-C main engines 10 having a 6-cylinder derating specification and two propellers 20.

The output of the 7-cylinder S80MC-C main engine 1 with a normal specification of 7 cylinders included in the VLCC of FIG. 2A is 27160 kW, and the fuel consumption is 167 g / kWh. If the main engine is derated and the fuel consumption is reduced by about 7% to 155 g / kWh, the output per cylinder will be reduced by about 35%, so the number of cylinders will need to be increased to 11. The engine room manager needs to be increased by about 7m.
On the other hand, in the VLCC of FIG. 2B, since two S80MC-C main engines 10 having a 6-cylinder derating specification are mounted, the fuel consumption is about 7 times that of the VLCC of FIG. % Decrease to 155 g / kWh, while the output is 29760 kW, which is equal to or higher than that of the VLCC in FIG. 2A, and the engine room length is about 1.4 m (one cylinder) shorter than the VLCC in FIG. Yes.
In the two-machine two-shaft VLCC of FIG. 2B, the stern shape in the vicinity of the two propellers 20 arranged in the same number as the main engine 10 is mounted on the stern of FIG. An increase in hull resistance is suppressed by approximating the shape of the stern near the propeller of one VLCC propeller. By installing two derating specification two-stroke diesel main engines, the cylinder diameter is prevented from increasing and the width of each main engine 10 is prevented from increasing, so the stern near each propeller 20 becomes thicker. Is prevented, and the increase in hull resistance is suppressed.

In the above embodiment, two machines and two axes are used, but n machines and n axes (n ≧ 3) may be used.
The present invention is not limited to VLCC but can be applied to large ships in general.

It is a figure which shows the specification of S80MC-C main engine of B & W. It is a general layout of VLCC. (A) is a general layout diagram of a one-machine one-shaft VLCC equipped with a seven-cylinder normal specification S80MC-C main engine 1 and one propeller. (B) is a general layout diagram of a two-machine two-shaft VLCC equipped with two six-cylinder derating specification S80MC-C main engines 10 and two propellers 20.

Explanation of symbols

1, 10 S80MC-C main engine 2, 20 propeller

Claims (1)

A low-fuel-consumption main engine-equipped ship equipped with a plurality of derating specification two-stroke diesel main engines and equipped with the same number of propellers at the stern as the main engines.

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