JPH01302114A - Airflow measuring device - Google Patents

Abstract

PURPOSE:To improve labor effectiveness by a method wherein air quantities when an air collector is set or when it is removed are measured and an opening ratio of an outlet or inlet calculated from their ratio is used for measuring an air quantity of another outlet or inlet. CONSTITUTION:Points 231-23n for measuring wind velocity are specified at a position where a wind direction is arranged under a condition that an upper opening of a blown-off air collector 20 is engaged with an air outlet 4, and a sensor portion 25a of a hot wire anenometer 25 is set to measure wind velocity. Then average wind velocity is calculated by an arithmetic unit 26, and an air quantity X is calculated by multiplying it and an opening section area of the collector 20. Next, wind velocity of a blown-off part of an air outlet 4 is measured with the collector 20 removed, to calculate an air quantity Y. Since a ratio k obtained by dividing the air quantity X with the air quantity Y is a substantial opening ratio of the air outlet 4, when measuring air quantities at air outlets of the same shape, an air quantity can be calculated by multiplying the ratio k and the air quantity obtained from wind velocity at the air outlet.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an air volume measuring method for measuring the volume of air blown or sucked into an opening such as an air outlet or suction port of an air conditioner.

[Conventional technology]

When air conditioning each room in an office building or other building, a refrigerator is used as part of the air conditioning equipment.

An air conditioner consisting of a blower, boiler, pump, and other attached equipment is installed in a mechanical room such as a basement, and the temperature of the air sent to each room by this air conditioner is determined by the temperature of the air sent to each room.

After adjusting the humidity, the main duct distributes the air to each room, and the return duct returns the air to the machine room. In particular, on the air conditioning room side, as shown in Fig. 8, a branch duct 2 branched from the main duct 1 of one air conditioning system is connected to a plurality of air outlets 4 arranged in the room 3, and each Conditioned air is blown into the room 3 from the air outlet 4, and a branch duct 6 branched from one air conditioning system duct 5 is connected to a suction lower installed in the room 3, and indoor air is supplied from each suction lower. It is designed to maintain the indoor pressure at a predetermined level and to maintain a predetermined ventilation rate in the room.

However, since the pressure loss of the duct and the pressure loss of the outlet or suction port cannot be clearly set at the design stage, the branch duct 2
main damper 8 provided at the connection with the main duct) 1. Appropriate air volume can be achieved by adjusting the damper 9 provided in each air outlet 4 or the main damper 10 provided at the connection between the branch duct 6 and the return duct 5, and the damper 11 provided in each blow lower. ing.

Moreover, examples of the air outlet applied to the above-mentioned central type air conditioning equipment have structures shown in FIGS. 9 and 10. That is, the conditioned air sent through the duct 2 passes through the damper 9, is bent at 90'' at the top of the outlet 4, and is blown into the room through the diffusion fins 4a arranged at the opening of the outlet 4.

In this way, there are many obstacles in the air path up to the outlet 4, and the fins 4a are arranged at the opening of the outlet 4, so there is a difference in the amount of air blown out between each fin 4a. Moreover, since the flow direction of the blown air is different, even if the wind speed blown out from between the fins 4a is directly measured, the true amount of air blown out from the effective opening of the air outlet 4 can be determined from the measured wind speed value. I can't.

Therefore, the usual method is to attach a cylindrical air collector to the outlet, keep the flow of air from the outlet constant, measure the wind speed, and calculate the outlet air volume from this wind speed. There is. This also applies to the suction port.

As a first method of actual air volume measurement using the above method, as shown in FIG.
The large cross-sectional area base 12a of No. 2 is set in the air outlet 4 (or suction port) so that it is covered, and the blowing fan 13 is attached to the tip opening of the narrow cross-sectional area cylindrical portion 12b. The sensor section 15a of the anemometer 15 is inserted into the wind speed measuring port 14 formed on the side surface of the tip side. In this state, the rotation speed of the fan 13 is adjusted while watching the pressure gauge 16 so that the pressure at the insertion position of the sensor part 15a becomes atmospheric pressure, and the wind speed at the atmospheric pressure state is measured with the anemometer 15.

The air volume is calculated by multiplying the obtained wind speed by the cross-sectional area of the throttle tube part 12b where the sensor part 15a is attached.

In addition, as a second method, Fig. 12 (a) and (b)
As shown in the figure, one end opening of a rectangular cylindrical blown air collecting body 17 formed to have an external dimension that surrounds the outer periphery of the blowing outlet 4 (or suction port) is attached to the blowing outlet 4, and the other end inside the air collecting body 17 is attached to the blowing outlet 4. A plurality of measurement points 18 are set on the opening side (or the middle part), and the sensor part 15a of the anemometer 15 is set at each measurement point 18 to measure the wind speed, and the obtained wind speed for each measurement point is averaged. , the air volume is calculated by multiplying this average wind speed by the cross-sectional area of the rectangular tube at the measurement location.

Other methods include the first method, which is a simple method that does not use the pressure regulating fan 13, and a method in which the fins 4a of the air outlet 4 are removed and the air volume is measured.

[Problem to be solved by the invention]

In the conventional airflow measurement method as described above, the first method sets the pressure at the measurement site to atmospheric pressure, so it is possible to obtain a value close to the true wind speed. If there are fluctuations in the amount of air being blown or sucked into the machine, the pressure at the measurement site will fluctuate, making it very difficult to maintain the pressure at atmospheric pressure. It takes time to measure wind speed because it requires setting up a fan, anemometer, pressure needle, etc. In addition, there are many measuring instruments, and pressure gauges, anemometers, and air collection bodies for measurement must be transported to the measurement location for each outlet or inlet, which requires a large number of workers. There was a problem.

In addition, in the second method, since the cross-sectional area of the air collecting body 16 of the wind speed measurement unit is almost the same as the opening area of the air outlet (or suction port), the wind speed can be measured at multiple locations within the same plane. must be measured and averaged, but there is no need to take pressure fluctuations into account, so there is no need to adjust the pressure. However, since the air collecting body 17 must be attached to each outlet or inlet to measure the wind speed regardless of whether the outlet or inlet is the same, it takes a lot of manpower and time to measure the wind speed. However, there was a problem in that the measurement work was complicated and the accuracy of wind speed measurement was affected.

The present invention solves the above-mentioned problems, and eliminates the need to attach an air collector to each outlet or inlet to measure wind speed, thereby reducing measurement time and manpower. An object of the present invention is to provide an air volume measurement method that enables reliable air volume measurement at low cost.

[Means to solve the problem]

The method for measuring air volume according to the present invention is to measure the wind speed at multiple points within the cross section of the air collector with an anemometer with the air collector set at the outlet or suction port to adjust the wind direction. Calculate the first air volume by multiplying this average wind speed by the cross-sectional area of the measurement part of the air collector, and then calculate the wind speed at multiple locations of the same outlet or inlet with the air collector removed. Measure directly with an anemometer to find the average wind speed at all measurement points, multiply this average wind speed by the area of the outlet or inlet to calculate the second air volume, and divide the first air volume by the second air volume. The aperture ratio of the air outlet or suction port is determined, and thereafter, for air outlets or suction ports of the same shape, the air volume can be measured by multiplying the air volume directly determined from this by the aperture ratio.

[For production]

In the present invention, the effective opening area ratio of the outlet or suction port is calculated from the air volume with the air collector set at the outlet or suction port and the air volume of the same outlet or suction port with the air collector removed. For air outlets or inlets of the same shape, the air volume can be measured in advance by simply multiplying the air volume directly calculated by the aperture ratio determined in advance. An air collecting body is not required to measure the air volume of a shaped outlet or suction port, making it possible to save manpower and reduce costs for air volume measurement.

〔Example〕

Hereinafter, embodiments of the method of the present invention will be described in detail based on the drawings.

When measuring the air volume of the air outlet, as shown in FIG. 4 to surround it, and the worker 2
Hold by 1. Thereafter, on the lower end opening 20a (air outflow side) side of the air collecting body 20, a part parallel to the outlet 4 where the wind direction is adjusted is set as a wind speed measurement level 22, and a transverse plane of the air collecting body 20 including this wind speed measurement level 22. As shown in FIG. 1(b), there are a plurality of wind speed measurement points 23. ~237
and set each measurement point 23. ~237 other worker 2
Set the sensor part 25a of the hot wire anemometer 25 carried by person 4, and measure the wind speed aI%3 at each measurement point 231-237. are measured sequentially. The wind speed data a1 to a7 at the measurement points measured by the anemometer 25 are sequentially taken into the arithmetic device 26 connected to the anemometer 25, and the average wind speed A of all the measurement points is calculated.

Thereafter, by operating the keyboard 27 provided on the calculation device 26, the opening cross-sectional area of the air collecting body 20 is inputted to the calculation device 26, and this cross-sectional area is multiplied by the average wind speed A to calculate the wind 1x.

Next, after removing the air collecting body 20 from the air outlet 4, as shown in FIG. Then, the wind speed is measured using an anemometer 25.

In this case, the measurement point for the air outlet 4 is not limited to one location,
As in the case shown in FIG. 1(b), there are multiple locations.

Measured wind speed data 01 to C7 at each measurement point at the air outlet 4
are sequentially taken into the arithmetic unit 26, and the average wind speed C at all measurement points is calculated. Then, by operating the keyboard 27, the area d of the air outlet 4 is input into the arithmetic unit 26 and multiplied by the average wind speed C to obtain the air volume Y.

Next, the ratio k is obtained by dividing the air volume X when using the air collector 20 by the air volume Y of the outlet 4. This ratio k becomes the actual opening ratio of the air outlet 4.

When measuring the air volume of an outlet that has the same shape and area as the outlet 4, use the sensor at multiple measurement points set at the outlet in the same manner as described in Fig. 2. 25a in sequence to measure the wind speed C'1 to C1 at each measurement point.
1 are sequentially measured, and the obtained wind speeds c'1 to C17 are taken into the arithmetic unit 26 and added, and then divided by the number of measurement points to obtain the average wind speed C' at the outlet. Thereafter, the obtained average wind speed C' is multiplied by the area d of the outlet used to calculate the ratio and the aperture ratio k determined in advance, and the arithmetic unit 26 executes the calculation of c'xctxk=z. Calculate the air volume Z.

On the other hand, when measuring the air volume of an outlet that has the same shape as the outlet 4 but has a different area, use the same method for measuring the area d used to calculate the ratio.
11 is determined in advance. Then, in the same manner as above, the wind speeds C''1 to C''7 at each measurement point are sequentially measured to determine the average wind speed C'', and the area d'' of this outlet determined in advance is added to the average wind speed C''.
is multiplied by the aperture ratio k, and the arithmetic unit 26 executes the calculation of C''×d''Xk=Z'' to calculate the airflow i1Z at the outlet.

FIG. 3 is a process diagram showing the steps of the above-described method for measuring the air flow rate of the outlet in blocks.

In this embodiment as described above, the air collector 20 is set at the outlet, and the wind speed at multiple locations within a cross section parallel to the outlet 4 is adjusted with the air collecting body 20 set at the outlet and the direction of the air blown from the outlet being adjusted. is measured, and the air volume X is determined by multiplying the average wind speed A obtained from the plurality of measurement points and the cross-sectional area of the measured part of the air collector 20, and then the same air outlet 4 with the air collector 20 removed. Find the air volume of the air outlet 4 from the average wind speed C and its area d, and calculate the air volume ratio X/Y=k (opening ratio of the air outlet)
Based on this, the air volume of other outlets with the same shape is calculated, so when measuring the air volume of outlets with the same shape, set the air collector 20 to any one outlet and calculate the air volume. All you have to do is measure it, and for the other outlets, simply find the average wind speed using the anemometer 25 and the calculation device 26, and multiply this by the cross-sectional area of the outlet 4 and the aperture ratio k determined in advance. The air volume of other outlets can be measured, and as a result, there is no need to attach an air collector to every outlet to measure the air volume as in the past, making it easier to measure the air volume of each outlet. In addition to significantly reducing the time required for measurement, it also improves work efficiency. Further, since the air volume can be measured by one worker except when determining the aperture ratio k, it is possible to easily realize labor saving and cost reduction in in-measurement.

Figures 4 and 5 show an embodiment of the sensor support mechanism for stably positioning and supporting the sensor part in a fixed position at each measurement point of the air outlet. FIG. 5 is a front view thereof.

In the figure, positioning metal fittings 31a are placed above and below the sensor part 25a attached to the tip of the sensor support rod 30.
, 31b are fixed at one end, and the other end is extended horizontally, and hook portions 32a, 32b that are engaged with the fins 4a of the air outlet 4 are formed at the tips thereof.

Therefore, when setting the sensor section 25a at the measurement point of the air outlet 4 when measuring the wind speed of the air outlet 4, the positioning metal fitting 31
The hook portions 32a and 32b of the fins 4a and 31b are engaged with the edges of the fins 4a, and in this state, the entire sensor portion 25a is attached to the fins 4a.
When pressed against the flat surface of the fin 4a, the sensor portion 25a
The sensor part 25a can be stably set in a fixed state, and accordingly, the sensor part 25a will not swing and disturb the blowing airflow, making it possible to accurately measure the wind speed.

6 and 7 show other embodiments of the sensor support mechanism for the air outlet, and FIG. 6 is a cross-sectional plan view of the main part;
FIG. 7 is a front view thereof.

In the figure, a sensor section 25 is attached to the tip of the sensor support rod 30.
A sheath tube 33 is provided, into which the sheath tube 33 is inserted, and set rods 34a and 34b of a desired length extending in the left and right horizontal directions are bored in the upper and lower parts of the sheath tube 33.

When setting the sensor section 25a at the measurement point of the air outlet 4 using the support mechanism configured as described above, the set rods 34a, 34b are
is pressed against the front edge between adjacent fins 4a, 4a. As a result, the sensor section 25a including the sheath tube 33 has fins 4a,
It will be stably positioned and held within the airflow between 4a.

In this embodiment as well, the same effects as in the above embodiment can be obtained.

In the above embodiment, only the air volume measurement at the outlet was explained, but it goes without saying that the present invention can also be applied to the measurement of the air volume at the suction port.

〔Effect of the invention〕

As described above, according to the method of the present invention, the average wind speed is determined by measuring a plurality of wind speeds in the cross section of the air collecting body with the air collecting body adjusting the wind direction set at the outlet or suction port, The air volume is calculated by multiplying this average wind speed by the cross-sectional area of the measurement area, and then the average wind speed is determined by measuring the wind speed at multiple locations of the same outlet or inlet with the air collector removed using an anemometer. , calculate the air volume by multiplying this average wind speed by the area of the air outlet or suction port, and calculate the aperture ratio of the air outlet or suction port by dividing the air volume by the air collector by this air volume. For an outlet or suction port, the air volume is calculated by multiplying the measured wind speed and area by the above-mentioned aperture ratio, so no air collector is required to measure the air volume of an outlet or suction port with the same shape. This makes it easier to measure airflow, reduces the time required for measurement, improves work efficiency, and allows one worker to measure airflow except when determining the aperture ratio. This has the effect of reducing manpower and cost for measuring airflow.

[Brief explanation of the drawing]

FIG. 1(a) is a schematic diagram of an air volume measuring means using an air collector at an outlet or a suction port according to the air volume measuring method of the present invention. FIG. 1(b) is an explanatory diagram showing wind speed measurement points in FIG. 1(a). FIG. 2 is a schematic diagram of a means for measuring air volume at an outlet or inlet according to the method of the present invention. FIG. 3 is a process diagram showing, in block form, the air volume measurement procedure in an embodiment of the method of the present invention. FIG. 4 is a cross-sectional plan view of essential parts showing an embodiment of the sensor support mechanism for the air outlet (or suction port) of the wind speed sensor according to the present invention. FIG. 5 is a front view of FIG. 4. FIG. 6 is a cross-sectional plan view of essential parts showing another embodiment of the sensor support mechanism according to the present invention. FIG. 7 is a front view of FIG. 6. FIG. 8 is a system diagram showing the relationship between the duct, the outlet, and the inlet of the air conditioning equipment. FIG. 9 is a schematic sectional view showing the connection relationship between the air outlet and the duct. FIG. 10 is a front view of the air outlet. FIG. 11 is a schematic configuration diagram of a conventional outlet airflow measuring means. FIG. 12(a) is a schematic configuration diagram showing another example of the same conventional outlet air volume measuring means. FIG. 12(b) is an explanatory diagram showing wind speed measurement points in FIG. 12(a). [Explanation of symbols of main parts] 4...Air outlet 4a...Fin 20...Air collector 22...Wind speed measurement levels 231-237...Measurement point 25...Anemometer. 25a...Sensor section 26...Arithmetic device 27...Keyboard.

Claims (1)

[Claims] (1) With an air collector set at the outlet or suction port to adjust the wind direction, measure the wind speed at multiple points within the cross section of the air collector using an anemometer to determine the average wind speed within the cross section. Calculate the first air volume by multiplying by the cross-sectional area of the measurement part of the air collector, and then measure the wind speed at multiple locations of the same outlet or inlet with the air collector removed using an anemometer. Find the average wind speed at all measurement points, multiply this average wind speed by the area of the outlet or inlet to calculate the second air volume, and divide the first air volume by the second air volume to calculate the air outlet or inlet. An air volume measuring method characterized in that the air volume can be measured by determining the aperture ratio of the air outlet or suction port having the same shape, and then multiplying the air volume directly determined from the air volume by the aperture ratio.