JP2010002356A - Method, apparatus and program for measuring difference in acting force - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method, an apparatus and a program for measuring a difference in acting force for correctly evaluating, for example, a difference in frictional resistance depending on a type of a coating film in the water, a difference in frictional resistance of different surface states or the like as a minute difference by using two objects with a very small difference in acting force when activated. <P>SOLUTION: The apparatus accurately measures a difference in resistance by measuring the resistance of two testing plates placed in parallel, moment between the testing plates and resistance force. In concrete, the method for measuring the difference in resistance force is characterized by that it includes steps of driving the two objects under test simultaneously under the same conditions, measuring a change including the moment and/or resistance force occurring on the two objects, and evaluating at least the difference in the resistance force. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to, for example, an acting force measurement method, an acting force measurement device, and an acting force difference measurement program.

  For example, in research on marine paints that reduce marine frictional resistance of ships, the difference from ordinary paints is very small.

On the other hand, in the field of patents, for example, a technical idea as disclosed in Patent Document 1 is disclosed. However, this technical idea is far from solving the above measurement difficulty.
JP 2004-212135 A

  The present invention solves the above-mentioned problems of the prior art, and uses two specimens having a small difference in acting force when operated, for example, a difference in frictional resistance depending on the type of coating film in water. Another object of the present invention is to provide an acting force difference measuring method, an acting force difference measuring apparatus, and an acting force difference measuring program capable of correctly evaluating a difference in frictional resistance between different surface states as a minute difference.

In order to achieve such an object, in the present invention, two test objects are simultaneously operated under the same conditions, for example, by measuring the resistance between two test plates installed in parallel and the moment between the test plates, This is achieved by evaluating the difference in acting force, such as measuring the difference in resistance with high accuracy.
Specifically, the method for measuring a difference in acting force according to claim 1 of the present invention is a method in which two test objects are simultaneously operated under the same conditions, and a change including a moment and / or an action force generated in the two test objects is performed. And at least the difference in acting force is evaluated.

In the method for measuring a difference in acting force according to claim 2 of the present invention, two test objects are simultaneously driven under the same condition, and a change including moment and / or resistance force generated in the two test objects is measured. It is characterized by evaluating at least the resistance difference.

  Further, the acting force difference measuring method corresponding to claim 3 of the present invention is characterized in that, when two test objects are simultaneously driven under the same conditions, other physical quantities that cause a difference by driving are also measured simultaneously. The resistance force difference measuring method according to claim 2 is configured.

  Furthermore, an acting force difference measuring device corresponding to claim 4 of the present invention is a locking mechanism for locking two test objects, and a moment measurement for measuring a moment and / or a resistance force acting on the locking mechanism. Means and / or resistance force measuring means, driving means for driving the two test objects through at least the locking mechanism, and the moment measuring means and / or when the two test objects are driven by the driving means Alternatively, the moment and / or resistance force is measured by the resistance force measuring means.

  Further, the working force difference measuring device corresponding to claim 5 of the present invention includes a related physical quantity detecting means for simultaneously measuring other physical quantities that are caused by driving when two test objects are driven simultaneously under the same conditions. Furthermore, it is comprised as an action force difference measuring apparatus of Claim 4 characterized by the above-mentioned.

  In the acting force difference measuring device corresponding to claim 6 of the present invention, the two test objects are driven in water, and the moment measuring means and / or the resistance force measuring means are connected to the two test objects. 5. The acting force difference measuring device according to claim 4, wherein a difference in acting fluid resistance is detected as a moment and / or a resistance force.

  The acting force difference measuring device corresponding to claim 7 of the present invention is a locking mechanism portion for locking two flat plates facing underwater, a spring means for applying a stress corresponding to displacement to the locking mechanism, A moment measurement galvanometer and / or galvanometer for measuring the moment and / or resistance force acting on the locking mechanism, and a driving means for driving the two test objects through at least the locking mechanism; The moment measurement and / or the force measurement is performed by the moment measuring force meter and / or the force meter when the two flat plates are driven by the driving means.

  The acting force difference measurement program corresponding to claim 8 of the present invention drives a computer under the same conditions at the same time for two DUTs, and changes in changes including moments and / or resistance forces generated in the two DUTs. Measurement instruction means for instructing measurement, data acquisition means for acquiring measurement results, data processing means for processing data acquired a plurality of times, and resistance of the two test objects from the processing results of the data processing means And a resistance force difference calculating means for calculating the difference between the resistance force difference and the output means for outputting the result of the resistance difference calculating means and / or the data processing means.

  By being configured as described above, by operating the two DUTs simultaneously under the same conditions, the error factor is greatly reduced as compared with the case of individually evaluating.

  For example, in a towed water tank, residual flow, rail height, water temperature distribution, static vibration, and the like cause errors. Therefore, by simultaneously testing two flat plates to be tested, the error factor is considerably reduced.

  More specifically, two flat plates coated with general paint and friction resistance-reducing paint are supported by springs and suspended, and at the same time, moved in the water tank under the same conditions. The difference in resistance generated as a frictional resistance is enlarged by an arm (torque rod) that holds two flat plates and measured as a moment by a moment measuring device. For this reason, a slight difference in frictional resistance can be easily detected as a moment.

  Of course, this concept is not only used in water, but also in air such as wind tunnels, and on roads such as rolling resistance of tires. Of course, there is a difference in propeller propulsion and injection port difference. It can be considered that it can be used for the object to be measured with respect to any object with a slight difference in the acting force such as a difference in driving force of the wheel.

  Furthermore, it is possible to extend the measurement to any other physical quantity that causes a difference in noise or temperature at the same time as measuring the resistance difference. Furthermore, the frictional resistance difference may be measured, and the frictional force of each plate may be detected, that is, the acting force itself may be measured. Further, a change in the position of the two flat plates appearing as a result of the difference in frictional resistance may be captured as an image, and at least the difference in acting force may be evaluated. Such a technical idea can be realized as a method, an apparatus, and a program.

By operating two DUTs under the same conditions at the same time, differences in test conditions, such as the effects of timing and time, etc., and differences in all physical conditions related to the test, can be minimized. The difference in acting force that could not be discriminated can be measured.
In addition, since the change including the moment and / or acting force generated in the two DUTs is measured and at least the acting force difference is evaluated, for example, by connecting the flat plate with a torque rod, the difference in resistance value is obtained by the moment. Therefore, it is possible to accurately measure a small difference. Further, by measuring the acting force itself, the acting force difference as an absolute value can be evaluated. Further, by evaluating the difference in acting force through the measurement result, the difference between the two test objects can be immediately understood. Moreover, by realizing as an apparatus, it does not take time to prepare for measurement, and measurement can be easily performed without being an expert. Furthermore, by realizing as a program, the captured data can be easily processed, and the result can be easily confirmed by the output means.

As an embodiment of the present invention, an apparatus for measuring the difference in frictional resistance of a flat plate in water will be described below as an example.

The outline of the apparatus is shown in FIGS. 1 to 6 and described below.
・ The equipment with the test plate is installed on the towing cart of the towing tank. As the tow truck travels, the test flat plate advances while the lower surface is immersed in the water surface. At this time, the moment generated from the difference between the resistance applied to the test flat plate and the resistance of the left and right flat plates is measured.
・ Two test flat plates are fixed on a base suspended by a leaf spring or a swing to restrain the relative movement in the lateral direction.
-In the method of measuring the resistance of each of the two test flat plates, measurement is performed with two dynamometers corresponding to the respective test flat plates.
In the method of measuring the difference in resistance between two test plates, the moment applied to the torque rod connecting the two test plates is measured with a galvanometer (for moment measurement).
• Install two test flat plates at an interval that allows the influence of mutual interference between waves and flows generated by the flat plates to be considered from the size and test speed.
・ Each flat plate has a strain gauge in the vicinity of the mounting part, and can measure lateral force. Using the measured lateral force, the mounting accuracy of the test flat plate can be verified. (Of course, it is better that the lateral force is small.) Also, the alignment can be adjusted while looking at the lateral force.
-A turbulent boundary layer test is possible by installing a turbulent flow device.
・ If the turbulence enhancement is removed, the effect of the transition from laminar to turbulent flow can be evaluated.

An example of application of this technical idea to resistance difference measurement is shown below.
・ Evaluation of swimsuit material ・ Evaluation of turbulence promoting device ・ Use other than flat plate (ship model, human model with swimsuit)
・ Use in circulating water tank (ship model, human model with swimsuit)
・ Use in wind tunnel (airfoil, aircraft, automobile, bicycle, railway vehicle)
-Towing (actual sea area, underwater, air)
・ Tire rolling resistance test ・ Bearing rolling resistance test In addition, examples of simultaneous measurement of other physical quantities that cause a difference due to driving are shown below.
・ Measurement of lift of objects in fluid ・
Measurement of streamlines of objects in fluid
Measurement of vibration of objects in fluid
・ Image shooting with tufts and tracers of objects in the fluid ・
・ Measurement of tire running noise ・
Measurement of wind noise of pantograph In other words, any resistance received from each of these phases when an object under test moves in the liquid phase, gas phase, or on the solid phase of various substances, materials, and so on. It is possible to measure and evaluate the difference between them and the change in physical quantity accompanying them.
Moreover, this technical idea can be expanded not only as a resistance difference but also to a concept such as a difference in action force, and examples thereof include the following application examples.
・ Propeller and screw propulsion force ・ Nozzle injection force ・ Wheel drive force ・ Brake braking force ・ Friction force of material ・ Magnetic force accompanying the movement of the object, that is, changes when two specimens are operated It can be developed for various measurements.

Development of high precision coating film friction measurement method using parallel plates The ratio of the frictional resistance between seawater and the hull surface to the total resistance of the ship that sails first is about 50-80%. Therefore, reducing the frictional resistance generated between the seawater and the painted surface of the hull is an effective means for reducing the propulsion resistance of the ship and achieving energy saving. Therefore, in order to develop a paint that can reduce the frictional resistance against water flow compared to the existing marine paints, the National Maritime Research Institute “R & D of basic technology for marine paints that reduces seawater frictional resistance” "It is carried out.
In order to develop and evaluate such paints, we would like to evaluate the difference in frictional resistance of about 1% in the external flow. In the conventional tank test in a towing tank, the effects of resistance components other than frictional resistance, It was extremely difficult to evaluate the difference in friction resistance of 1% due to the influence of internal disturbance. Therefore, we decided to develop a measurement method that can accurately evaluate frictional resistance using a method of towing two flat plates in parallel.
2. Outline of measurement method and equipment In resistance measurement in towing tanks, the effects of other resistance components such as wave resistance and shape resistance, residual current in the tank, the effects of static vibration, temperature gradients, etc. cause error factors, resulting in measurement accuracy. It has a great influence on. Therefore, two flat plates of the same shape are arranged in parallel and towed, and the difference in resistance is measured to eliminate the influence of these error factors as much as possible, and the difference in frictional resistance with water of the DUT is accurately measured. A measuring method that can be evaluated was devised, and a high-precision frictional resistance measuring device was manufactured as the measuring device.
The high-precision frictional resistance measuring device is a device that simultaneously measures the resistance of two flat plates suspended in parallel to the lower part of the device. The flat plate is suspended in a swing manner via front and rear leaf springs, and the relative movement in the lateral direction is restricted. The test plate was an aluminum plate with a thickness of 10 mm, and the front end and rear end were provided with a rectifying cover having a cross-sectional shape of the arc blade, thereby reducing the wave-making resistance component and the pressure resistance component. A stud type turbulence promoting device is attached to the front rectifying cover. The left and right plates are 2m away from each other to avoid hydrodynamic interference
Are attached at intervals. The resistance applied to each flat plate is measured by a force meter installed between two leaf springs that suspend the flat plate. In addition, the right and left flat plates are connected with rods, and the moment applied to them is measured with a force meter for moment measurement, thereby providing the function of measuring the difference in resistance between the two flat plates as a moment. The external appearance of the device is shown in FIG.

3. Verification test A verification test of the high-precision frictional resistance measurement method was conducted in the third vessel test tank of the National Maritime Research Institute. In the verification test, the effect of promoting turbulence was confirmed, and the reproducibility of the difference in resistance between the left and right plates was confirmed. The test speed range was 0.5m / s to 4.5m / s, and the speed was changed every 0.5m / s. The flat plate used for the test is the same specification on both the left and right sides, and is an unpainted aluminum plate whose surface is anodized. During the resistance test, the temperature gradient of the water temperature in the depth direction is large, and at the start of the experiment on the first day, the water depth is 5 cm.
There was a temperature difference of 3.6 ° C between 70 cm and 70 cm 2. A photograph of the device installed on the towing cart is shown in FIG.

  FIG. 9 shows a comparison of the resistance measurement result and the frictional resistance coefficient obtained by the Schoenherr equation. The measurement results show that the boundary layer on the flat plate is in a turbulent state.

Subsequently, the ratio of the difference in resistance between the left and right flat plates to the average of the total resistance of the left and right flat plates is shown in FIG.
Four
Difference in resistance between the right and left plates The right and left plates and the rectifying cover have the same specifications and shape, so there should be no difference in resistance. This is considered to be a difference caused by the mounting state of the accelerating device and the mounting accuracy of the flat plate to the device. FIG. 11 shows the change in the ratio of the difference between the resistances of the left and right flat plates to the average of the total resistance of the left and right flat plates when the test is repeated at 4.0 m / s.

As a result of nine repeated tests, the resistance difference was distributed in the range of about 0.1%.
4). Finally, a high-accuracy frictional resistance measuring device that enables evaluation of minute resistance differences caused by surface properties such as the type of coating by towing the flat plates in parallel was produced and verified. As a result, it was confirmed that the reproducibility of the resistance difference between the left and right plates was very high even though the temperature gradient was large and the conditions in the water tank were quite bad. In the future, we plan to paint the flat plate and evaluate the difference in resistance due to the properties of the coating film.
In these measurements, a personal computer is used to instruct the measurement, the force meter for moment measurement or the force meter data is captured multiple times, the captured data is processed, and the resistance force and resistance force The difference is calculated and output to the screen of the personal computer according to the selection according to the application.
The series of operations is constructed as a personal computer program, but is operated on various terminals to implement information processing functions, software, such software that can be executed on a recording medium, ROM ( Read-only memory), an algorithmized electronic circuit, and the like.

  Note that the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

  Further, the above-described examples are merely examples of embodiments for realizing the technical idea according to the present invention, and the technical ideas according to the present invention can be applied to other embodiments. Is possible.

  According to the present invention, two flat plates coated with general paint and friction resistance-reducing paint are supported by springs and suspended, and at the same time, moved in the water tank under the same conditions. The difference in resistance generated as a frictional resistance is enlarged by an arm (torque rod) that holds two flat plates and measured as a moment by a moment measuring device. For this reason, a slight difference in frictional resistance can be easily detected as a moment. For example, it can be applied to the comparison between the recently-known Speed Company swimsuits and other companies' swimsuits.

Further, this concept is considered to be applicable not only to underwater applications but also to applications that generate a lot of resistance such as in the air such as wind tunnels and on roads such as rolling resistance of tires. Therefore, not only a ship but also an object can be used for measurement of all resistances and their differences received from each phase by moving various substances, materials in the liquid phase, in the gas phase, or on the solid phase.
Furthermore, it can be expanded not only to application as resistance and resistance difference, but also to the concept of evaluation of action force and action force difference associated with the operation of an object, and is highly applicable to various industries.

It is a figure which shows one Embodiment of this invention. It is a figure which shows one Embodiment of this invention. It is a figure which shows one Embodiment of this invention. It is a figure which shows one Embodiment of this invention. It is a figure which shows one Embodiment of this invention. It is a figure which shows one Embodiment of this invention. It is a figure which shows one Embodiment of this invention. It is a figure which shows one Embodiment of this invention. It is a figure which shows one Embodiment of this invention. It is a figure which shows one Embodiment of this invention. It is a figure which shows one Embodiment of this invention.

Claims (8)

  Working force difference measurement characterized in that two specimens are operated simultaneously under the same conditions, changes including moments and / or acting forces generated in the two specimens are measured, and at least the acting force difference is evaluated. Method.   Actuation force difference measurement characterized in that two specimens are driven simultaneously under the same conditions, changes including moments and / or resistance forces generated in the two specimens are measured, and at least the resistance difference is evaluated. Method.   3. The method of measuring a difference in acting force according to claim 2, wherein when two test objects are simultaneously driven under the same conditions, other physical quantities that are different due to the drive are also measured simultaneously.   A locking mechanism for locking the two test objects, a moment measuring means and / or a resistance measuring means for measuring a moment and / or a resistance force acting on the locking mechanism, and at least via the locking mechanism A driving means for driving the two DUTs, and a moment and / or resistance force measurement by the moment measuring means and / or the resistance measuring means when the two DUTs are driven by the driving means; A device for measuring difference in acting force. 5. The differential force measuring apparatus according to claim 4, further comprising a related physical quantity detecting means for simultaneously measuring other physical quantities that are caused to be different by driving when two test objects are driven simultaneously under the same conditions. .   The two test objects are driven in water, and the moment measuring means and / or the resistance force measuring means detects a difference in fluid resistance acting on the two test objects as a moment and / or a resistance force. 5. The acting force difference measuring device according to claim 4,   A locking mechanism portion for locking two flat plates facing underwater, a spring means for applying a stress corresponding to displacement to the locking mechanism, and a moment and / or a resistance force acting on the locking mechanism are measured. Moment measuring force meter and / or force meter, driving means for driving the two test objects through at least the locking mechanism, and for driving the two flat plates by the driving means A working force difference measuring device characterized by performing moment measurement and / or resistance force measurement with a galvanometer and / or galvanometer. The computer,
A measurement instructing means for instructing measurement of changes including moments and / or resistance forces generated in the two DUTs simultaneously under the same conditions, and data fetching means for taking in the measurement results; Data processing means for processing data taken a plurality of times, resistance force difference calculating means for calculating a difference in resistance force between the two test objects from the processing result of the data processing means, the resistance force difference calculating means, An acting force difference measurement program for functioning as output means for outputting the result of the data processing means.