JPH0544763Y2 - - Google Patents

Description

[Detailed explanation of the idea]

[Industrial Application Field] The present invention relates to a tufted grid for visualizing wind direction distribution such as in wind cylinder experiments. It is particularly applicable to measurements sensitive to light winds. [Summary of the invention] The tuft grid of the present invention is a system in which a large number of tufts are arranged on one side of the flow, and the wind direction distribution in the wake of an object or in the cross section of the flow of the flow path is visualized. It is characterized by the application of ultra-fine wire to reduce resistance, and the material used is spring material for watches (product name: Spron material).
It is a combination of φ20 to 50μm of wire tuft made of the same material and φ15μm or less of ultra-fine wire tuft made of the same material.The grids are crossed, one end of the tuft is attached to this, and the behavior of the free end of the other end is used to control the wind direction distribution. It realizes visualization. [Conventional technology and issues] The technology related to this invention is described in the document ``New Edition'', for example.
It is disclosed in ``Flow Visualization Handbook'' (edited by Flow Visualization Chemistry Society), and Chapter 4 on page 135 relates to the Taft method. Representative examples of conventional general tufts, particularly those related to measurements in light winds, are shown in side views in Figures 5A to 5D, and front views of the entire structure including frame 1 are shown in Figures 6A, B, and C. Shown below. Many of the grids 2 and tufts 7 that make up these are made of fibers, and the tufts 7 in particular are made of the materials shown in Table 1. Therefore, in grid 2, the grid material is thick and has a large resistance, so there is a problem in visualizing the wind direction distribution at light wind speeds, and in tuft 7, the tuft material is thick, so there is a problem in visualizing the wind direction distribution at light wind speeds.

[Problem that the invention attempts to solve]

Both the tuft 7 and the grid 2 shown in FIG. 5 have thick materials, which have a large resistance and low sensitivity to slight wind speed, making visual measurement difficult. Furthermore, since they are made of fibers, both the grid and tuft have low mechanical strength, and in particular, the tension of grid 2 is affected by humidity and temperature, causing it to sag over a long period of time, and tuft 7 has a problem in that fine hairs come off. It was hot. Grids made of piano wire were used to solve these problems, but they had problems such as difficulty in making the wire thinner and lack of tensile strength. The present invention aims to solve these problems. [Means for Solving the Problems] In order to solve the problems of the prior art, the present invention provides an intersecting grid in a frame, fixes one end of a plurality of tufts to the grid, and fixes the free ends of the tufts to the grid. In the tufted grid, which follows the wind flow and detects the distribution of wind direction by the following, the grid is made of a wire with a diameter of 20 to 50 μm, the tension of which is at least 10 grams and maximum 55 grams, and is corrosion-resistant. Made of a material with constant elastic properties, the tuft has a diameter
The problem is solved by making the grid 15 μm or less and 10 μm or more and made of the same material as the grid. [Example] Hereinafter, an example of the present invention will be described based on the drawings. First, as a method of attaching the grid 2 to the grid frame 1 which is a frame, FIGS. 1 to 3 are perspective views of fixing the ends of the grid 2 according to the embodiment of the present invention. An example of how to attach the ultra-fine wire grid 2 is shown. A method is shown in which a V-groove 3 is carved in a grid frame 1, an ultra-fine wire grid is stretched on the lower surface of the V-groove 3, and fixed with a connecting agent 4. The installation method shown in FIG. 2 is to embed a pin 5 in the grid frame 1, entangle the ultra-fine wire grid 2 around the pin 5, and fix it with a connecting agent 4. The attachment method shown in FIG. 3 is to make a hole 6 in the grid frame 1 and pass the fine wire grid 2 through the hole 6 and fix it with a connecting agent 4. In all of these methods, sufficient tension is applied to secure the grid 2 so that it does not sag. Regarding this tension and the wire diameter of grid 2, if the diameter is 50 μm or more, the air resistance will be too large.
If the diameter was less than 15 μm, sufficient tension could not be obtained. 4A, B, and C show the main part of the structure for fixing the tuft 7 to the grid 2 intersecting with the grid frame 1, and the cross section of one of the grids 2 is shown as the plane of the paper. Although the length of the tuft 7 to the free end is 30 to 60 mm, it is shown broken and omitted. In Figure A, one end of the tuft 7 is wrapped diagonally around the intersection of grid 2 so that the restraint does not hinder the free movement of the tuft, and In this example, the adhesive 4 is applied to the intersection of the tips of the tufts 7 when adhering the sides and the tufts. In Figure B, the tuft 7 is wound diagonally around the intersection of the grid 2, and when gluing the tuft 7 to the vertical and horizontal sides of the grid 2, adhesive is applied to fix one end of the winding of the tuft 7 and the vertical and horizontal sides of the grid 2. This is an example. Furthermore, in Figure C, the tuft 7 is wrapped diagonally around the intersection of the grid 2, and when gluing the tufts to the length and width of the grid 2, one side that does not go over the tuft 7 and the application of adhesive to fix the length and width of the grid 2 are applied. These bonding methods can be selected as required, and it is not necessary to attach the tufts 7 only to the intersections of the grids 2 as in this embodiment. In addition, adhesives include adhesives (modified acrylate type), instant adhesives (cyanoacrylate type),
Good adhesive strength was obtained with two-component adhesives (epoxy adhesives), silicone adhesives, chemical glues, etc. Here, the feature of the present invention is that the above-mentioned grid 2 and tuft 7 are both made of the same metal material, and in this embodiment, it has the special characteristics of being applied to the mainspring material of a wristwatch. Are known. Due to its unique properties, even when the wire is thinned from φ20μm to φ50μm, its breaking strength (tension strength) remains at a minimum of 10 grams and a maximum of 55 grams, and changes in tension even under a wide range of temperature conditions. There is no. In addition, the luminosity of metal in tufts is effective in reflecting light, making visibility clear. The thinner the tuft that follows this weak wind, the better.
There are limits to processing, and on the other hand, the thicker it is, the less sensitive it is to wind. Due to this balance, the practical range for the diameter of the tuft was φ15 μm or less, which was the machining limit of 10 μm. [Effects of the Invention] As described above, the present invention has the effect of making it possible to visualize the wind speed distribution at very small wind speeds through the configuration of the ultra-fine wire tuft and the ultra-fine wire grid. Since it is made of metal, it does not suffer from fatigue or deterioration, and is particularly effective in many ways, including the use of reflected light when taking flash photography with a strobe and measurement using electric fields in analyzing wind direction behavior.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of an embodiment in which the grid of the present invention is attached to a V-groove. FIG. 2 is a perspective view of an embodiment of the present invention in which the grid is attached to a pin. FIG. 3 is a perspective view of an embodiment of the present invention in which the grid is installed in a hole. 4A, B, and C are cross-sectional views of an embodiment in which the tuft of the present invention is attached to a grid. Fifth
Figures A, B, C, and D are side views of conventional tufts. 6A, B, and C are front views of conventional grids. 1... Grid frame, 2... Grid, 4... Adhesive, 7... Tuft.

Claims (1)

[Scope of utility model registration request] A tuft grid in which an intersecting grid is provided in a frame, one end of a plurality of tufts is fixed to the grid, the free ends of the tufts follow the flow of the wind, and the distribution of the wind direction is detected by the following, The grid is made of a wire rod with a diameter of 20 to 50 μm, and its breaking strength is at least 10 grams and at most 55 grams, and is made of a material that is resistant to contact and has constant elastic properties. Tufted Grit is characterized by being made of the same material as Grit.