A variable frequency ventilation system for a ship's engine room and its control method

Abstract

This invention discloses a variable frequency ventilation system for a ship's engine room and its control method. By arranging two main engines in the same engine room space without separating them by a bulkhead, and independently separating two generator rooms for storing generators within the engine room space, the engine room and the two independent generator rooms within the engine room are supplied with air by their respective corresponding fans. This can ensure the normal operation of the main engines and generators, and can adjust the fan operating frequency in real time according to the operating status of the main engines and generators, so as to save energy and reduce power consumption.

Description

Technical Field

[0001] This invention relates to the field of shipbuilding technology, and in particular to a variable frequency ventilation system for a ship's engine room and its control method. Background Technology

[0002] A conventional ship's propulsion system typically consists of one main engine and several generators, all housed in an engine room. Air is supplied to the entire engine room by several fans of equal capacity, consuming a significant amount of combustion air during operation. However, LNG carriers have two main engines and four generators. If, following a conventional ship design, all four generators were placed in the same engine room, relying on fans of equal capacity for air supply, the required air volume would be too large to meet the operational demands of the generators and main engines. Simply increasing the number of fans to increase air volume would consume excessive amounts of electricity. Therefore, how to rationally arrange the main engines and generators, and how to optimize the air duct layout to ensure energy-efficient fan operation, becomes a pressing issue. Summary of the Invention

[0003] In view of this, the present invention provides a variable frequency ventilation system for ship engine room and its control method to solve the problems existing in the background art.

[0004] A variable frequency ventilation system for a ship's engine room includes an engine room, a first fan room and a second fan room independently located outside the engine room, and an independent first generator room and second generator room are provided inside the engine room. The first generator room and the second generator room are respectively connected to the internal space of the engine room through their respective air outlets, and the engine room is connected to the outside through its air outlets.

[0005] The first fan room is equipped with a first fan and a second fan. The first fan supplies air to the nacelle through a first air supply duct, and the second fan supplies air to the first generator room through a second air supply duct.

[0006] The second fan room is equipped with a third fan and a fourth fan. The third fan supplies air to the nacelle through the third air supply duct, and the fourth fan supplies air to the second generator room through the fourth air supply duct.

[0007] Multiple generators are arranged in both the first generator room and the second generator room. Both the first generator room and the second generator room are equipped with temperature sensors for detecting the temperature in their respective spaces and differential pressure sensors for detecting the pressure difference between their respective spaces and the cabin.

[0008] The cabin is equipped with a first main engine and a second main engine. The cabin is also equipped with a temperature sensor for detecting the temperature inside the cabin and a differential pressure sensor for detecting the pressure difference between the cabin and the outside.

[0009] Preferably, a first generator and a second generator are arranged in the first generator room;

[0010] The second generator room contains the third and fourth generators.

[0011] Preferably, the first fan, the second fan, the third fan, and the fourth fan are each independently controlled by frequency converters to independently adjust the temperature and pressure difference between the inside and outside of the first generator room, the second generator room, and the nacelle room.

[0012] Preferably, the first generator room and the second generator room are arranged symmetrically, and the first generator room and the second generator room share a bulkhead.

[0013] Preferably, the system further includes a first frequency converter for controlling the first fan, a second frequency converter for controlling the second fan, a third frequency converter for controlling the third fan, and a fourth frequency converter for controlling the fourth fan, wherein the first, second, third, and fourth frequency converters are controlled by an IAS control system.

[0014] A control method for a variable frequency ventilation system in a ship's engine room specifically includes the following steps:

[0015] When the first and second main units are not in operation, the first and third fans operate at the lowest frequency and supply air to the nacelle with the minimum displacement.

[0016] When the first host and / or the second host are running, the operating frequency of their respective fans is adjusted according to the operating load of the first host and / or the second host. When the temperature inside the nacelle is greater than the set value, the operating frequency of the fan corresponding to the currently running host is increased until the temperature inside the nacelle is equal to the set value. When the pressure difference between the inside and outside of the nacelle is less than the set value, the operating frequency of the fan corresponding to the currently running host is increased until the pressure difference between the inside and outside of the nacelle is equal to the set value.

[0017] When the generators in the first generator room and / or the second generator room are running, the fan corresponding to the currently running generator operates at the lowest frequency. When the temperature inside the first generator room and / or the second generator room is greater than the set value, the operating frequency of the fan corresponding to the currently running generator is increased until the temperature inside the first generator room and / or the second generator room equals the set value. When the pressure difference between the inside and outside of the first generator room and / or the second generator room is less than the set value, the operating frequency of the fan corresponding to the currently running generator is increased until the pressure difference between the inside and outside of the first generator room and / or the second generator room equals the set value.

[0018] Preferably, the specific steps for adjusting the operating frequency of the corresponding fan according to the operating load of the first host and / or the second host are as follows:

[0019] When the main unit load is 0-15%, the fan operating load is 30Hz;

[0020] When the main unit load is 15%-25%, the operating load of the fan is 35Hz;

[0021] When the main unit load is 25%-35%, the fan operating load is 40Hz;

[0022] When the main unit load is 35%-80%, the fan operating load is 45Hz;

[0023] When the main unit load is 80%-39%, the fan operating load is 50Hz;

[0024] When the main unit load is 90%-100%, the operating load of the fan is 60Hz.

[0025] Preferably, the pressure difference setting value between the inside and outside of the generator room is greater than the pressure difference setting value between the inside and outside of the engine room;

[0026] The temperature setting in the generator room is 2°C higher than the temperature setting in the engine room.

[0027] The beneficial effects of this invention are:

[0028] 1. This invention arranges two main units in the same cabin space without separating them by a cabin wall, and independently separates two generator rooms for storing generators within the cabin space. The cabin and the two independent generator rooms within the cabin are ventilated by their respective corresponding fans, which can ensure the normal operation of the main units and generators and can adjust the operating frequency of the fans in real time according to the operating status of the main units and generators, so as to save energy and reduce power consumption.

[0029] 2. This invention sets up the generator room inside the engine room, with airflow connecting the generator room and the engine room. If the fan supplying air to the engine room fails, the fan supplying air to the generator room can be used to indirectly supply air to the engine room, thus ensuring the normal operation of the main unit.

[0030] 3. Temperature sensors and differential pressure sensors are installed in both the engine room and the generator room. Based on the detection signals from the temperature sensors and differential pressure sensors, the operating frequency of the corresponding fan can be dynamically adjusted to ensure that the temperature in the engine room and the differential pressure inside and outside the room meet the requirements. Attached Figure Description

[0031] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 This is a schematic diagram of the layout of the variable frequency ventilation system in the ship's engine room.

[0033] The meanings of the labels in the diagram are as follows:

[0034] First fan 1, second fan 2, third fan 3, fourth fan 4;

[0035] First air supply duct 5, second air supply duct 6, third air supply duct 7, fourth air supply duct 8;

[0036] First generator room 9, second generator room 10;

[0037] First host 11, second host 12;

[0038] First generator 13, second generator 14, third generator 15, fourth generator 16;

[0039] First temperature sensor 17, first differential pressure sensor 18, second temperature sensor 19, second differential pressure sensor 20, third temperature sensor 21, third differential pressure sensor 22, first air outlet 23, second air outlet 24, third air outlet 25;

[0040] First frequency converter 26, second frequency converter 27, third frequency converter 28, fourth frequency converter 29, IAS control system 30;

[0041] Cabin 31;

[0042] First fan room 32, second fan room 33. Detailed Implementation

[0043] To make the objectives, technical solutions, and advantages of this invention clearer, the invention is described below with reference to specific embodiments shown in the accompanying drawings. However, it should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0044] The terminology used in this disclosure is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. The singular forms “a,” “the,” and “the” as used in this disclosure and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any and all possible combinations of one or more of the associated listed items.

[0045] To better understand the technical solution of the present invention, the present invention will be described in detail below with reference to the accompanying drawings.

[0046] The present invention provides a variable frequency ventilation system for a ship's engine room, including an engine room 31, a first fan room 32 and a second fan room 33 independently located outside the engine room 31.

[0047] The engine room 31 contains a separate first generator room 9 and a second generator room 10. A third air outlet 25 is provided on the engine room 31, allowing it to communicate with the outside world. Air within the engine room 31 flows out through the third air outlet 25. A first main unit 11 and a second main unit 12 are arranged in the engine room 31. In this embodiment, the first main unit 11 and the second main unit 12 are arranged symmetrically on the left and right sides.

[0048] The first generator room 9 is provided with a first air outlet 23, and the first generator room 9 is connected to the internal space of the engine room 31 through its first air outlet 23. The air in the first generator room 9 flows to the engine room 31 through the first air outlet 23. Multiple generators are arranged in the first generator room 9. In this embodiment, two generators are arranged in the first generator room 9, namely the first generator 13 and the second generator 14.

[0049] The second generator room 10 is provided with a second air outlet 24, and the second generator room 10 is connected to the internal space of the engine compartment 31 through its second air outlet 24. The air in the second generator room 10 flows to the engine compartment 31 through the second air outlet 24. Multiple generators are also arranged in the second generator room 10. In this embodiment, two generators are arranged in the second generator room 10, namely the third generator 15 and the fourth generator 16.

[0050] The first fan room 32 is equipped with a first fan 1 and a second fan 2. The first fan 1 supplies air to the nacelle 31 through the first air supply duct 5, and the second fan 2 supplies air to the first generator room 9 through the second air supply duct 6.

[0051] The second fan room 33 is equipped with a third fan 3 and a fourth fan 4. The third fan 3 supplies air to the nacelle 31 through the third air supply duct 7, and the fourth fan 4 supplies air to the second generator room 10 through the fourth air supply duct 8.

[0052] The first fan 1, the second fan 2, the third fan 3, and the fourth fan 4 are each independently controlled by frequency converters to independently regulate the temperature and pressure difference between the inside and outside of the first generator room 9, the second generator room 10, and the nacelle room 31. Each fan is regulated by its corresponding frequency converter. The first fan 1 is controlled by the first frequency converter 26, the second fan 2 by the second frequency converter 27, the third fan 3 by the third frequency converter 28, and the fourth fan 4 by the fourth frequency converter 29. The first frequency converter 26, the second frequency converter 27, the third frequency converter 28, and the fourth frequency converter 29 are all controlled by the IAS control system.

[0053] The first generator room 9 and the second generator room 10 are also equipped with temperature sensors for detecting the temperature in their respective spaces and differential pressure sensors for detecting the pressure difference between their respective spaces and the cabin 31. In this embodiment, the temperature sensor in the first generator room 9 is a first temperature sensor 17 and the differential pressure sensor is a first differential pressure sensor 18; the temperature sensor in the second generator room 10 is a second temperature sensor 19 and the differential pressure sensor is a second differential pressure sensor 20.

[0054] The cabin 31 is equipped with a temperature sensor for detecting the temperature of its cabin space and a differential pressure sensor for detecting the pressure difference between its cabin and the outside. In this embodiment, the temperature sensor of the cabin 31 is a third temperature sensor 21 and the differential pressure sensor is a third differential pressure sensor 22.

[0055] The first temperature sensor 17, the second temperature sensor 19, the third temperature sensor 21, the first differential pressure sensor 18, the second differential pressure sensor 20, and the third differential pressure sensor 22 all transmit the signals they detect to the IAS control system. The IAS control system controls the corresponding frequency converters based on the signals it receives, and then controls the corresponding fans to achieve real-time adjustment of the temperature or the pressure difference between the inside and outside of the space in the first generator room 9, the second generator room 10, or the nacelle room 31.

[0056] Preferably, the first generator compartment 9 and the second generator compartment 10 are arranged symmetrically, and the first generator compartment 9 and the second generator compartment 10 share a bulkhead.

[0057] The present invention also provides a control method for the above-described ship engine room frequency conversion ventilation system, specifically including the following steps:

[0058] S1, when the first host 11 and the second host 12 are not running, the first fan 1 and the third fan 3 operate at the lowest frequency and supply air to the nacelle 31 with the minimum displacement.

[0059] S2, when the first host 11 and / or the second host 12 are operating normally, the operating frequency of their respective fans is adjusted according to the operating load of the first host 11 and / or the second host 12. When the temperature inside the nacelle 31 is greater than the set value, the operating frequency of the fan corresponding to the currently operating host is increased until the temperature inside the nacelle 31 is equal to the set value. When the pressure difference between the inside and outside of the nacelle 31 is less than the set value, the operating frequency of the fan corresponding to the currently operating host is increased until the pressure difference between the inside and outside of the nacelle 31 is equal to the set value.

[0060] When the first host 11 is operating normally and the second host 12 is malfunctioning, the operating efficiency of the first fan 1 is adjusted according to the operating load of the first host 11, and the second fan 2 operates at the lowest frequency. The relationship between the operating load of the first host 11 and the operating frequency of the first fan 1 is shown in the table below:

[0061] Host load 0-15％ 15％-25％ 25％-35％ 35％-80％ 80％-89％ 90％-100％ Lowest frequency (Hz) 30 35 40 45 50 60

[0062] When the temperature inside the nacelle 31 is greater than the set value TT1 (TT1 = 42℃), the operating frequency of the first fan 1 is increased until the temperature inside the nacelle 31 equals the set value; when the pressure difference between the inside and outside of the nacelle 31 is less than the set value DP1 (DP1 = 5Pa), the operating frequency of the first fan 1 is increased until the pressure difference between the inside and outside of the nacelle 31 equals the set value.

[0063] Conversely, when the second host 12 is running normally and the first host 11 is malfunctioning, the control logic is the same as the control logic for "the first host 11 is running and the second host 12 is malfunctioning".

[0064] When both the first host 11 and the second host 12 are running, the operating frequencies of the first fan 1 and the second fan are dynamically adjusted according to the load of each host and the relationship between the host load and the fan operating frequency in the table above, so that the temperature inside the nacelle 31 and the pressure difference between the inside and outside of the nacelle (the pressure difference between the inside and outside of the nacelle refers to the pressure difference between the pressure inside the nacelle 31 and the external atmospheric pressure) meet the requirements.

[0065] S3, when the generators in the first generator room 9 and / or the second generator room 10 are operating normally, the fan corresponding to the currently operating generator operates at the lowest frequency. When the temperature inside the first generator room 9 and / or the second generator room 10 is greater than the set value TT2 (TT2 = 40℃), the operating frequency of the fan corresponding to the currently operating generator is increased until the temperature inside the first generator room 9 and / or the second generator room 10 is equal to the set value. When the pressure difference between the inside and outside of the first generator room 9 and / or the second generator room 10 is less than the set value DP2 (DP2 = 20Pa), the operating frequency of the fan corresponding to the currently operating main unit is increased until the pressure difference between the inside and outside of the first generator room 9 and / or the second generator room 10 (the pressure difference between the inside and outside of the room refers to the pressure difference between the internal pressure of the generator room and the internal pressure of the nacelle) is equal to the set value.

[0066] When the generator in the first generator room 9 is running normally, the second fan 2 operates at the lowest frequency. When the indoor temperature in the first generator room 9 is greater than the set value TT2, the operating frequency of the second fan 2 is increased until the indoor temperature equals the set value TT2. When the pressure difference between the inside and outside of the first generator room 9 is less than the set value DP2, the operating frequency of the second fan 2 is increased until the pressure difference between the inside and outside of the room equals the set value DP2.

[0067] Similarly, when the generator in the second generator room 10 is running normally, the control logic of the fourth fan 4 is the same as that of the second fan 2 when the generator in the first generator room 9 is running normally.

[0068] The pressure difference setting value DP2 between the inside and outside of room 9 / 10 of the generator room is greater than the pressure difference setting value DP1 between the inside and outside of room 9 / 10 of the engine room.

[0069] The temperature setting TT2 in room 9 / 10 of the generator room is 2℃ higher than the temperature setting TT1 in the engine room, where TT1 = TT2 + 2℃.

[0070] It should be understood that the described embodiments are merely some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

Claims

1. A variable frequency ventilation system for a ship's engine room, characterized in that, It includes a nacelle (31), a first fan room (32) and a second fan room (33) independently located outside the nacelle (31). The nacelle (31) is equipped with an independent first generator room (9) and a second generator room (10). The first generator room (9) and the second generator room (10) are respectively connected to the internal space of the nacelle (31) through their respective air outlets. The nacelle (31) is connected to the outside through its air outlets. The first fan room (32) is equipped with a first fan (1) and a second fan (2). The first fan (1) supplies air to the nacelle (31) through the first air supply duct (5), and the second fan (2) supplies air to the first generator room (9) through the second air supply duct (6). The second fan room (33) is equipped with a third fan (3) and a fourth fan (4). The third fan (3) supplies air to the nacelle (31) through the third air supply duct (7), and the fourth fan (4) supplies air to the second generator room (10) through the fourth air supply duct (8). Multiple generators are arranged in the first generator room (9) and the second generator room (10). The first generator room (9) and the second generator room (10) are equipped with temperature sensors for detecting the temperature in their respective spaces and differential pressure sensors for detecting the pressure difference between their respective spaces and the cabin (31). The cabin (31) is equipped with a first host (11) and a second host (12). The cabin (31) is equipped with a temperature sensor for detecting the temperature of its cabin space and a differential pressure sensor for detecting the pressure difference between its cabin and the outside. The first fan (1), the second fan (2), the third fan (3) and the fourth fan (4) are each independently controlled by frequency conversion to independently adjust the temperature and pressure difference between the inside and outside of the first generator room (9), the second generator room (10) and the nacelle room (31).

2. The ship engine room frequency conversion ventilation system according to claim 1, characterized in that, The first generator room (9) is equipped with a first generator (13) and a second generator (14). The second generator room (10) is equipped with a third generator (15) and a fourth generator (16).

3. The ship engine room frequency conversion ventilation system according to claim 1, characterized in that, The first generator compartment (9) and the second generator compartment (10) are arranged symmetrically, and the first generator compartment (9) and the second generator compartment (10) share a bulkhead.

4. The ship engine room frequency conversion ventilation system according to claim 1, characterized in that, It also includes a first frequency converter (26) for controlling the first fan (1), a second frequency converter (27) for controlling the second fan (2), a third frequency converter (28) for controlling the third fan (3) and a fourth frequency converter (29) for controlling the fourth fan (4), wherein the first frequency converter (26), the second frequency converter (27), the third frequency converter (28) and the fourth frequency converter (29) are controlled by the IAS control system.

5. A control method for a ship engine room variable frequency ventilation system according to any one of claims 1-4, characterized in that, Specifically, the following steps are included: When the first host (11) and the second host (12) are not running, the first fan (1) and the third fan (3) operate at the lowest frequency and supply air to the nacelle (31) with the minimum displacement; When the first host (11) and / or the second host (12) are running, the operating frequency of their respective fans is adjusted according to the operating load of the first host (11) and / or the second host (12). When the temperature inside the nacelle (31) is greater than the set value, the operating frequency of the fan corresponding to the currently running host is increased until the temperature inside the nacelle (31) is equal to the set value. When the pressure difference between the inside and outside of the nacelle (31) is less than the set value, the operating frequency of the fan corresponding to the currently running host is increased until the pressure difference between the inside and outside of the nacelle (31) is equal to the set value. When the generators in the first generator room (9) and / or the second generator room (10) are running, the fan corresponding to the currently running generator runs at the lowest frequency. When the temperature in the first generator room (9) and / or the second generator room (10) is greater than the set value, the operating frequency of the fan corresponding to the currently running generator is increased until the temperature in the first generator room (9) and / or the second generator room (10) is equal to the set value. When the pressure difference between the inside and outside of the first generator room (9) and / or the second generator room (10) is less than the set value, the operating frequency of the fan corresponding to the currently running generator is increased until the pressure difference between the inside and outside of the first generator room (9) and / or the second generator room (10) is equal to the set value.

6. The method according to claim 5, characterized in that, The specific steps for adjusting the operating frequency of the corresponding fan according to the operating load of the first host (11) and / or the second host (12) are as follows: When the main unit load is 0-15%, the operating load of the fan is 30Hz; When the main unit load is 15%-25%, the operating load of the fan is 35Hz; When the main unit load is 25%-35%, the fan operating load is 40Hz; When the main unit load is 35%-80%, the fan operating load is 45Hz; When the main unit load is 80%-39%, the fan operating load is 50Hz; When the main unit load is 90%-100%, the operating load of the fan is 60Hz.

7. The method according to claim 5, characterized in that, The set value for the pressure difference between the inside and outside of the generator room is greater than the set value for the pressure difference between the inside and outside of the engine room. The temperature setting in the generator room is 2°C higher than the temperature setting in the engine room.

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