KR20160001731A - A method for estimating speed perfomance of floating structure - Google Patents
A method for estimating speed perfomance of floating structure Download PDFInfo
- Publication number
- KR20160001731A KR20160001731A KR1020140078603A KR20140078603A KR20160001731A KR 20160001731 A KR20160001731 A KR 20160001731A KR 1020140078603 A KR1020140078603 A KR 1020140078603A KR 20140078603 A KR20140078603 A KR 20140078603A KR 20160001731 A KR20160001731 A KR 20160001731A
- Authority
- KR
- South Korea
- Prior art keywords
- velocity
- power
- measuring
- speed
- marine structure
- Prior art date
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
- B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING
- B63B23/00—Equipment for handling lifeboats or the like
- B63B23/02—Davits, i.e. devices having arms for lowering boats by cables or the like
- B63B23/04—Davits, i.e. devices having arms for lowering boats by cables or the like with arms pivoting on substantially horizontal axes, e.g. gravity type
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
- B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING
- B63B27/00—Arrangement of ship-based loading or unloading equipment for cargo or passengers
- B63B27/30—Arrangement of ship-based loading or unloading equipment for transfer at sea between ships or between ships and off-shore structures
- B63B27/34—Arrangement of ship-based loading or unloading equipment for transfer at sea between ships or between ships and off-shore structures using pipe-lines
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
- G01P5/00—Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft
- G01P5/003—Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft by measuring fluid level in front of an obstacle
Abstract
The present invention relates to a method for measuring the speed performance of a marine structure, the method comprising the steps of: measuring a speed performance representing a relationship between a speed at which a marine structure is operated and a power consumed by the marine structure; Measuring a speed; Measuring power of the marine structure; Measuring an external resistance of the marine structure; Correcting the power using the external resistor; And generating velocity performance data using the corrected power and the logarithmic velocity.
The method of measuring velocity performance of a marine structure according to the present invention is a method for measuring the velocity performance of a marine structure by using a speed log which is provided in a marine structure and grasps a flow velocity through radio waves, Can be improved.
Description
The present invention relates to a method for measuring velocity performance of a marine structure.
In general, maritime structures such as ships are floated at sea using buoyancy and navigated at a constant speed using propulsion means such as a propeller. The speed performance which can be obtained according to the power consumed by the ship (for example, expressed in units of horsepower) can be varied depending on the specifications of the engine, the linearity of the ship, the frictional resistance or the wave resistance applied to the ship, have.
As the speed performance of the ship is increased, the speed of the ship can be increased with less power, which leads to the improvement of the fuel efficiency, thereby reducing the amount of fuel consumed in the operation of the ship. Therefore, as the speed performance of the ship is higher, it is possible to reduce the operation cost of the ship. Therefore, the ship owners have a great interest in the speed performance of the ship.
In particular, the International Maritime Organization (IMO) has proposed an energy regulatory policy to reduce carbon dioxide emissions, including the EEDI index (carbon dioxide emissions from shipments of 1 ton mile of cargo (1.852 km) The EEDI of ships with a gross tonnage of 400 GT or more should be reduced by 10% by 2015, 20% by 2020 and 30% by 2025, All are forbidden. Therefore, shipbuilders are continuously conducting research on fuel efficiency reduction vessels.
Due to this background, various attempts have been made recently to improve the speed performance of a ship. A method of installing an energy saving device (ESD: Energy Saving Device) which can use an engine having a good output efficiency, design a linear shape of a ship, or reduce frictional resistance, wave resistance and the like .
At this time, the speed performance of the ship is generally shown as a graph showing the correlation between speed and power. To generate such a graph, the power and speed must be measured. The power is measured by a torsion meter installed on the engine shaft, and the speed is measured by locating the ship by GPS.
However, in the case of speed measurement using GPS, even if the measured speed is 0, the ship may be moving in the opposite direction to the sea flow at the same speed as that of the sea, which is problematic. Also, The velocity measured by the GPS when it is floated by a bird or the like has a positive value, but it is hard to say that the velocity actually occurs.
Therefore, it is considered that the conventional speed performance measuring method using GPS is in need of improvement in consideration of the fact that the accuracy of data is low and the speed performance is evaluated to be very important.
SUMMARY OF THE INVENTION The present invention has been made to solve the above problems of the conventional art, and it is an object of the present invention to provide a GPS receiver and a GPS receiver, which can accurately recognize the speed performance of a marine structure using a speed log And to provide a method for measuring the speed performance of an offshore structure.
It is another object of the present invention to provide a marine structure capable of preventing an error from being generated due to the consumption of power by resistors by measuring power with a torsion meter and performing a correction operation after calculating resistance due to wind, Speed performance measurement method.
It is also an object of the present invention to provide a method and apparatus for measuring the speed of a vehicle using a speed log to accurately measure the speed, accurately grasp the power transmitted to the speed through the torsion meter and resistance measuring equipment, And to provide a method for measuring the speed performance of an offshore structure.
A method for measuring a speed performance of a marine structure according to an embodiment of the present invention is a method for measuring a speed performance indicating a relationship between a speed at which a marine structure is operated and a power consumed by the marine structure for navigation, Measuring a logarithmic velocity of the structure; Measuring power of the marine structure; Measuring an external resistance of the marine structure; Correcting the power using the external resistor; And generating velocity performance data using the corrected power and the logarithmic velocity.
Specifically, in the step of measuring the logarithmic velocity, a speed log provided in the sea structure may be used.
Specifically, in the step of measuring the logarithmic velocity, a value obtained by measuring the flow velocity of a sea area operated by the sea structure using radio waves may be outputted at the logarithmic velocity of the sea structure.
Specifically, the step of measuring the power may be performed by connecting a torsion meter to a driving source for generating power for operating the marine structure.
Specifically, the step of measuring the external resistance may measure an external resistance including at least one of a frictional resistance, a wave resistance, and an air resistance, excluding a resistance due to a flow velocity of a sea area operated by the sea structure.
Specifically, the step of correcting the power may remove the external resistance from the power.
Specifically, generating the velocity performance data may generate a graph that displays power based on the velocity.
The method of measuring velocity performance of a marine structure according to the present invention is a method for measuring the velocity performance of a marine structure by using a speed log which is provided in a marine structure and grasps a flow velocity through radio waves, Can be improved.
In addition, in the method of measuring velocity performance of a marine structure according to the present invention, an additional resistance due to a flow velocity can be taken into consideration by measuring velocity with a speed log, and frictional resistance or air resistance is measured separately and measured with a torsion meter By using it for the correction of the power, even when the speed performance is measured during navigation, it is possible not to cause an error with the speed performance data measured at the time of commissioning.
In addition, the method for measuring the speed performance of a marine structure according to the present invention makes it possible to sufficiently measure the speed performance with a short operation by eliminating the error between the speed performance measured at the start-up and the speed performance measured at the navigation, .
1 and 2 are graphs illustrating velocity performance of a marine structure through a conventional velocity performance measurement method.
3 is a flowchart of a method for measuring velocity performance of a marine structure according to an embodiment of the present invention.
FIG. 4 is a graph illustrating velocity performance of a marine structure through a method of measuring the velocity performance of a marine structure according to an embodiment of the present invention. Referring to FIG.
BRIEF DESCRIPTION OF THE DRAWINGS The objects, particular advantages and novel features of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: FIG. It should be noted that, in the present specification, the reference numerals are added to the constituent elements of the drawings, and the same constituent elements are assigned the same number as much as possible even if they are displayed on different drawings. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.
Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.
1 and 2 are graphs illustrating velocity performance of a marine structure through a conventional velocity performance measurement method.
In the conventional method of measuring the speed performance of a marine structure, in order to measure the speed performance of a marine structure such as a ship, a speed is measured by a GPS (for example, DGPS), a power is recorded by a torsion meter, have.
The speed performance is generally subject to rigorous verification through the drying and commissioning of the offshore structure. However, in case of commissioning, disturbances such as waves, winds, and currents act on the offshore structure, so DGPS is used to accurately measure the speed, and the ship will be operated on a return flight. In order to compensate for the power increase due to disturbance, various factors affecting the disturbance such as wind, wave, water temperature, water depth, draft, steering angle are measured and then standard analysis methods such as ISO, IMO and ITTC are applied The correction operation is performed.
The trend line for the speed performance can be formed by using the data obtained in this way. Since the trend line is based on data derived at the time of commissioning for accurately verifying external resistance, speed, or power, The speed performance of the vehicle.
However, in recent years, in addition to speed performance data acquired during test operation, there is an increasing need to verify whether the speed performance is displayed properly in a state where a marine structure is operated.
However, there are various external forces on the sea at the time of operation, and it is not possible to control the external conditions in order to increase the accuracy of the measurement. There are many difficulties in understanding accurate speed performance. Therefore, as shown in Fig. 1, the speed and power data measured during the flight depart from the trend line.
In a severe case, as shown in FIG. 2, data may not appear along a certain line but may appear scattered. That is, referring to FIG. 2, it can be seen that the speed varies in the same power. Since the velocity will increase when the offshore structure rides on the ocean current and the velocity will decrease when the wave height is high, it is difficult to grasp the objective and accurate performance of the offshore structure by the conventional velocity performance measurement method using GPS .
3 is a flowchart of a method for measuring velocity performance of a marine structure according to an embodiment of the present invention.
Referring to FIG. 3, there is provided a method of measuring a speed performance indicating a relationship between a speed at which a maritime structure is operated and a power consumed by the maritime structure, (Step S20) of measuring the power of the marine structure, step S30 of measuring the external resistance of the marine structure, step S40 of correcting the power using the external resistance, And generating data (S50).
In step S10, the logarithmic velocity of the marine structure is measured. The logarithmic velocity means the velocity at which a marine structure passes sea level. The speed log can be used for the speed log which is installed in the offshore structure. Speed log is a device for measuring the flow velocity of a sea structure operated by a sea structure using radio waves.
Specifically, the speed log is provided on the outside (for example, on the outside) of the marine structure, receives a radio wave that emits a radio wave such as an ultrasonic wave, and returns a radio wave. By using the Doppler effect through the frequency difference between the reception frequency and the transmission frequency, Can be measured.
In general, Speedlog can emit ultrasonic waves to the seafloor and measure the speed of the sea structure from the Doppler frequency included in the echo from the seabed, but the depth at the location of the sea structure can be more than 200m In this case, the attenuation increases and it becomes difficult to obtain the reverberation from the seabed. Thus, speed logs can utilize reflections from minute floats, plankton, or deeper water bodies near the sea level.
The velocity secured by the speed log is the logarithmic velocity, which means the relative speed at which the marine structure operates on the basis of sea level. Conventionally, because of the use of GPS, the speed of the sea structure could not be measured accurately because the sea surface was not considered to be moved by the algae. However, in the present embodiment, by using the speed log to measure the logarithmic velocity of the marine structure and to use it as the velocity of the marine structure for deriving the velocity performance data, even if the velocity of the marine structure changes due to the marine velocity, The speed at which the power is consumed can be grasped accurately.
In step S20, the power of the marine structure is measured. For power measurement, a torsion meter can be used. Power can be measured by connecting a torsion meter to the drive source, ie, the engine, which generates the power for operation of the offshore structure. Specifically, the torsion meter is connected to the drive shaft of the engine, and measures the power that the drive shaft rotates, thereby measuring the power generated by the drive source in units of horsepower.
The power of the offshore structure means the power consumed by the offshore structure. That is, even if the power generated by the engine is measured by using the torsion meter, the power consumed by the other equipment should be excluded when the power shaft is connected to the drive shaft connected to the engine.
In addition, when a plurality of engines or generators are used together without using one engine in the course of operating a marine structure, it is necessary to measure all the power used in the navigation. Therefore, a plurality of torsion meters can be used to measure the power. In the case of the electric propulsion system, a tachometer, a power meter for measuring the amount of power used in the operation, and the like can be used.
The power can be expressed in units of horsepower, and the present embodiment does not limit the unit of power to horsepower, of course. Since the present embodiment is intended to indicate the power to be input in order to secure the operating speed and the constant operating speed that can be obtained when a certain power is input, the unit of the power and the speed may be varied as needed.
In step S30, the external resistance of the marine structure is measured. The external resistance is not only the frictional resistance which is generated most during the operation of the offshore structure but also the wave resistance caused by the waves and the air resistance caused by the wind and the eddy resistance caused by the shape of the sea structure It is meant to include.
As a method of measuring the resistance, for example, it is possible to calculate the frictional resistance from the ITTC curve through the Reynolds number, or to calculate the wave resistance using the model line test, so that a detailed description thereof will be omitted .
In addition to the resistors listed above, the external resistors may include all of the forces that interfere with the operation of the offshore structure. However, the external resistance may include the resistance other than the resistance due to the flow velocity (algae velocity) of the sea area (sea surface) operated by the sea structure. This is because, as described in step S10, the resistance due to the flow rate has already been reflected in the correction in the process of measuring the logarithmic speed at the speed of the marine structure.
Specifically, it is considered that the operation of the offshore structure is facilitated by the tide (the tide direction and the direction of the operation of the offshore structure coincide with each other) or that the tide is obstructed (the direction of the tide direction is inconsistent with the direction of the tide structure) , The logarithmic velocity indicates the relative velocity of the sea structure with respect to sea level, and thus the velocity of the marine structure appears as the effect of algae is removed.
Therefore, if resistance included in the external resistance of step S30 is included in the flow velocity of the sea surface, an error may be generated in the velocity performance data as the resistance due to the flow velocity is corrected again in step S40 to be described later. The resistance is preferably excluded.
That is, since the resistance by the flow velocity is considered in step S10 in this embodiment, the resistance due to the flow velocity is reflected in the step S30 so that the power required to achieve the specified operating speed is reflected little Can be prevented from appearing.
In step S40, the power is corrected using an external resistor. As mentioned above, external resistance means friction resistance or wave resistance except resistance due to flow velocity. Correction of power by external resistance can not be used in all of the power generated by the power source to increase the operating speed, At least in part, by the resistor.
For example, if a power of 100 is generated, 20 can be depleted by resistance, and the remaining 80 can be used to create a speed. Therefore, in step S40, by performing correction by subtracting the
If the power is corrected by an external resistor, the calibrated power value can mean the power used for the speed of the operation. Therefore, when step S40 is completed, the power required to generate the logarithmic velocity in step S10 can be accurately grasped.
In step S50, velocity performance data is generated using the corrected power and the logarithmic velocity. The speed performance data may be a graph that displays the power depending on the speed. Since the corrected power is the power used to generate the navigation speed and the logarithmic velocity is the velocity of the offshore structure from which all the influences by the algae are removed, the velocity performance data using the corrected power and the logarithm speed Will be consistent with the velocity performance data of the offshore structure.
Therefore, by using the speed performance data in step S50, it is possible to accurately determine how much power is consumed to achieve a certain speed and what speed can be achieved when a certain amount of power is consumed. Thus, The performance data can be utilized as a data showing the operational performance of offshore structures.
Hereinafter, velocity performance results measured by the velocity performance measuring method of a marine structure according to an embodiment of the present invention will be described with reference to FIG.
FIG. 4 is a graph illustrating velocity performance of a marine structure through a method of measuring the velocity performance of a marine structure according to an embodiment of the present invention. Referring to FIG. In this case, the value indicated by A in FIG. 4 is added for the sake of explanation, but is not the data derived by this embodiment.
Referring to FIG. 4, the velocity performance data derived through the velocity performance measurement method of the marine structure according to an embodiment of the present invention closely matches the velocity performance data that can be derived at the time of commissioning.
That is, even if the speed performance data is generated by measuring the speed and the power during the operation, the present embodiment can accurately calculate the speed performance data by considering the flow velocity of the sea surface and the external resistance effectively.
In FIG. 4, the point A is a value obtained by measuring the speed by the GPS and the power by the torsion meter, without considering any external factors. At this time, the point A can be actually represented as the point A 'when it is calculated by the present embodiment.
The present embodiment does not use the GPS which does not consider the influence on the algae at all and instead uses the logarithmic velocity measured by using the speed log so that the velocity can be accurately derived. That is, as the present embodiment uses the logarithmic velocity, the point A can be shifted horizontally to the top of the point A '.
Alternatively, the present embodiment measures the external resistance and reflects the external resistance to the power, so that the power lost due to the external resistance can be corrected. Therefore, point A in the graph can be moved vertically to the left of point A '.
That is, the point A moves horizontally as the present embodiment uses the logarithmic velocity, and the present embodiment moves vertically considering the external resistance. Therefore, it can be seen that the point A according to the conventional velocity performance measurement method can be moved to the point A 'according to the present embodiment, and the point indicated as the point A' corresponds to the velocity performance graph at the time of commissioning, .
As described above, the present embodiment takes into consideration the influence of the algae (the influence of the sea level) by using the logarithmic velocity, reflects the external resistance after measuring the external resistance, Since the graph can be generated, it is possible to calculate accurate speed performance data and can be utilized as a reliable evaluation means for the navigation performance of the offshore structure.
However, since the speed performance of the offshore structure may be degraded as the use period elapses, the speed performance data measured by the present embodiment may be different from the speed performance data derived by the test run. However, this is due to the aging of the power source and the like, and it can be understood that the error is not an error of the speed performance data. However, according to the conventional method, since it is inevitable to estimate that the speed performance is degraded by a simple error, the present embodiment has an advantage that the speed performance is deteriorated clearly when compared with the conventional one.
While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the same is by way of illustration and example only and is not to be construed as limiting the present invention. It is obvious that the modification and the modification are possible.
It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.
Claims (7)
Measuring a logarithmic velocity of the marine structure;
Measuring power of the marine structure;
Measuring an external resistance of the marine structure;
Correcting the power using the external resistor; And
And generating velocity performance data using the corrected power and the logarithmic velocity.
Wherein the speed log of the sea structure is used.
Wherein the speed log estimates a value obtained by measuring a flow velocity using radio waves to a logarithmic velocity of the marine structure.
And a torsion meter is connected to a driving source for generating power for operating the marine structure, thereby measuring the velocity performance of the marine structure.
Wherein an external resistance including at least one of a frictional resistance, a wave resistance, and an air resistance is measured, excluding a resistance due to a flow velocity of the sea surface.
And the external resistance is removed from the power.
And generating a graph indicating the power according to the velocity.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR1020140078603A KR20160001731A (en) | 2014-06-26 | 2014-06-26 | A method for estimating speed perfomance of floating structure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR1020140078603A KR20160001731A (en) | 2014-06-26 | 2014-06-26 | A method for estimating speed perfomance of floating structure |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| KR20160001731A true KR20160001731A (en) | 2016-01-07 |
Family
ID=55168509
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| KR1020140078603A KR20160001731A (en) | 2014-06-26 | 2014-06-26 | A method for estimating speed perfomance of floating structure |
Country Status (1)
| Country | Link |
|---|---|
| KR (1) | KR20160001731A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20230047672A (en) * | 2021-10-01 | 2023-04-10 | 대우조선해양 주식회사 | Smart Speed Performance Evaluation System and Method for Ship |
-
2014
- 2014-06-26 KR KR1020140078603A patent/KR20160001731A/en not_active Application Discontinuation
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20230047672A (en) * | 2021-10-01 | 2023-04-10 | 대우조선해양 주식회사 | Smart Speed Performance Evaluation System and Method for Ship |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP3330171A2 (en) | Apparatus for predicting a power consumption of a maritime vessel | |
| Lang et al. | A semi-empirical model for ship speed loss prediction at head sea and its validation by full-scale measurements | |
| US11292570B2 (en) | Method and system for optimizing operation of vessel | |
| Tsujimoto et al. | Development of a calculation method for fuel consumption of ships in actual seas with performance evaluation | |
| JP2020158072A (en) | Vessel performance estimation method and vessel performance estimation system by assimilation of data | |
| KR20160089857A (en) | Estimation Method for Aging Effects of Ship, Estimation System for Aging Effects of Ship, Calculation System for Optimum Ocean Route, and Operation Support System of Ship | |
| CN104880186A (en) | Method and device for detecting offshore distance of ship | |
| EP3428655B1 (en) | Meter for ship speed relative to water and method for correcting measurement values of meter for ship speed relative to water | |
| Fonteinos et al. | Ship hull fouling estimation using shipboard measurements, models for resistance components, and shaft torque calculation using engine model | |
| CN111386467A (en) | Ship water velocity measuring device calibration method using numerical analysis | |
| Dhanak et al. | An autonomous ocean turbulence measurement platform | |
| KR20160001731A (en) | A method for estimating speed perfomance of floating structure | |
| Hasselaar et al. | Evaluation of an energy saving device via validation speed/power trials and full scale CFD investigation | |
| KR102421464B1 (en) | System and method for calculating eeoi and computer-readable recording medium thereof | |
| Ichinose et al. | Decrease of ship speed in actual seas of a bulk carrier in full load and ballast conditions-model test and onboard measurement | |
| Humphrey et al. | Variability of underwater radiated ship noise measured using two hydrophone arrays | |
| Haranen et al. | The role of accurate now-cast data in shi p efficiency analysis | |
| Saettone et al. | Experimental measurements of propulsive factors in regular deep-water following waves for a fishing trawler | |
| Shin et al. | Speed-Power Performance Analysis of an Existing 8,600 TEU Container Ship using SPA (Ship Performance Analysis) Program and Discussion on Wind-Resistance Coefficients | |
| Sogihara et al. | Verification of calculation method on ship performance by onboard measurement | |
| Svedendahl et al. | Underwater acoustic signatures from recreational boats | |
| CN204021221U (en) | The real ship measurement mechanism of inland navigation craft navigation deflection | |
| Kim et al. | Study on Data Analysis of On-Board Measurement Data for Ship’s Speed Power Performance | |
| Sogihara et al. | Onboard Measurement for Verification of a Calculation Method on Decrease of Ship Speed-for a RoRo Cargo Ship and an Oil Tanker | |
| JP6412642B2 (en) | Apparatus, system, method, and program for specifying ship speed against water |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| WITN | Withdrawal due to no request for examination |