JP2017181003A - Ventilation device and calculation method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ventilation device which depends neither on the shape of a device nor the installation place of the device, and which is capable of satisfactorily knowing an exhaust flow rate without receiving any influence of moisture and oil content contained in a gas ventilated; and a calculation method.SOLUTION: A controller C calculates an exhaust flow rate Q on the basis of a temperature T measured by a temperature measuring means, a differential pressure ΔP that is an absolute value of a difference between a first pressure and a second pressure, a specific reference temperature T, and the following equation 1. Q=a×(T/(T+T))×((T+T)/T×ΔP)(Equation 1), in which each of "a" and "b" is a constant number previously determined and stored in the controller C.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a ventilator that discharges the gas in the ventilation target area from the ventilation target area to the outside of the ventilation target area, and a calculation method of the exhaust flow rate Q that discharges the gas in the ventilation target area from the ventilation target area to the outside of the ventilation target area. About.

Conventionally, as a ventilation device that exhausts the gas in the ventilation target area from the ventilation target area to the outside of the ventilation target area, as shown in Patent Document 1, the exhaust duct that connects the ventilation target area and the outside of the ventilation target area, A fan that pumps out of the ventilation target area from the ventilation target area via the exhaust duct.
Such a ventilator measures the gas flow rate in the exhaust duct in order to keep the exhaust flow rate below the predetermined upper limit in order to prevent the exhaust flow rate from increasing too much and increasing the noise while keeping the exhaust flow rate above the predetermined lower limit. The flow rate sensor is provided, and the rotational speed of the fan is controlled based on the measured value of the flow rate sensor.

JP2015-114617A

In the technique disclosed in Patent Document 1, since the air volume sensor is provided in a state exposed to the gas flowing through the exhaust duct, for example, when the gas contains moisture or oil, There existed a problem that the said water | moisture content or oil component adhered to an air volume sensor, an air volume sensor deteriorated, or the measurement accuracy of an air volume sensor fell.
In order to avoid such a problem, it is conceivable to provide an air flow sensor at a portion of the exhaust duct where oil or moisture hardly adheres. However, the shape of the exhaust duct differs depending on the ventilation device and the installation location of the device. Therefore, it is necessary to examine the installation location and installation state of the air flow sensor for each ventilation device and each setting location, and there is room for improvement.

  The present invention has been made in view of the above-described problems, and the object thereof is not dependent on the shape of the device or the installation location of the device, and is affected by moisture and oil contained in the gas to be ventilated. The present invention relates to a ventilator that can know the exhaust flow rate well and a calculation method.

A ventilator for achieving the above object is:
A ventilation device that exhausts gas in the ventilation target area from the ventilation target area to the outside of the ventilation target area.
A blowing means for pumping the gas in the ventilation target area from the ventilation target area to the outside of the ventilation target area;
In the gas flow part for guiding the gas in the ventilation target area to the outside of the ventilation target area, the first pressure measurement means for measuring the first pressure and the temperature at the portion where the gas does not flow on the upstream side of the blowing means, Temperature measuring means for measuring;
Second pressure measuring means for measuring a second pressure in the ventilation target area;
Based on the temperature T measured by the temperature measuring means, the differential pressure ΔP that is the absolute value of the difference between the first pressure and the second pressure, the specific reference temperature T _0, and the following formula 1. The control device for calculating the exhaust flow rate Q is provided.
Q = a × (T ₀ / (T ₀ + T)) × ((T ₀ + T) / T ₀ × ΔP) ^b (Formula 1)
However, a and b are constants determined in advance and stored in the control device.

Also, the exhaust gas flow rate calculation method for achieving the above-mentioned purpose is as follows:
A method for calculating an exhaust flow rate for exhausting the gas in the ventilation target area from the ventilation target area to the outside of the ventilation target area.
In the gas flow part that guides the gas in the ventilation target area to the outside of the ventilation target area, the first pressure and the ventilation target in a part where the gas does not flow on the upstream side of the blowing means provided in the gas flow part The exhaust gas flow rate Q is calculated based on the differential pressure ΔP that is the absolute value of the difference from the second pressure in the region, the specific reference temperature T _0, and the following equation 1.
Q = a × (T ₀ / (T ₀ + T)) × ((T ₀ + T) / T ₀ × ΔP) ^b (Formula 1)
However, a and b are constants determined and stored in advance.

The inventors have studied diligently, and the exhaust flow rate Q by the ventilator is a static pressure as a first pressure measured at a portion where gas does not flow on the upstream side of the blowing means in the gas flow portion, Based on the above (Equation 1), it has been found that calculation can be performed with a high correlation with the actual measurement value from the differential pressure ΔP from the second pressure in the ventilation target region and the specific reference temperature T ₀ .
By adopting a configuration for calculating the exhaust flow rate Q as in the above feature configuration, there is no need to provide a flow sensor for measuring the exhaust flow rate discharged from the ventilation target area by the ventilator. In addition, the exhaust flow rate Q can be appropriately calculated without being affected by the adhesion of oil.
Further, according to the above characteristic configuration, for example, a sensor for measuring temperature as the temperature measuring means, a sensor for measuring the first pressure as the first pressure measuring means, and a sensor for measuring the second pressure as the second pressure measuring means are provided. However, the sensor that measures the temperature only needs to measure the temperature of the gas, and the sensor that measures the first pressure only needs to measure the static pressure of the gas. It may be provided at a portion where there is no gas flow. Moreover, since the sensor which measures 2nd pressure measures the pressure of a ventilation object area | region, it should just be provided in the site | part which is not exposed to a gas flow. That is, according to the said structure, it can avoid that the water | moisture content and oil content which are contained in gas adhere to sensors, and sensors deteriorate or the measurement precision of a sensor falls.

In addition, for example, a ventilator set in a home is often provided above a cooking utensil such as a stove. In such a setting mode, the temperature of the gas exhausted by the ventilator is low. It varies depending on whether or not it is used.
As described above, the inventors have derived the above formula 1 as a formula that can derive a good exhaust flow rate even when the temperature of the gas flowing through the gas flow section is different.

The inventors first discovered that the exhaust flow rate Q ₀ and the differential pressure ΔP _{0 at} the reference temperature T ₀ (for example, 273.15 K) have the relationship of the following formula 2.
Q ₀ = a × ΔP ₀ ^b (Formula 2)

Here, the exhaust flow rate Q ₀ at the reference temperature T _{0 and} the exhaust flow rate Q at the temperature T have the relationship of the following expression (3): the differential pressure ΔP _{0 at the} reference temperature T _{0 and} the differential pressure ΔP at the temperature T Has the relationship of Equation 4 below.
Q ₀ = (T ₀ + T) / T ₀ × Q (Formula 3)

ΔP ₀ = (T ₀ + T) / T ₀ × ΔP (Formula 4)

Further, Expression 1 obtained by substituting Expression 3 and Expression 4 into Expression 2 can calculate the exhaust flow rate Q with the same expression even when the temperature T is different.
Thereby, for example, in a case where the ventilator is configured to exhaust the exhaust from the stove or the like as a gas to the outside of the ventilation target area, and the temperature of the exhaust as the gas varies greatly depending on whether or not the stove is used. Even in such a case, the exhaust flow rate can be appropriately calculated by a single equation 1 in a state highly correlated with the actually measured value.
That is, according to the above characteristic configuration, the exhaust flow rate can be known well without being dependent on the shape of the device and the installation location of the device and without being affected by moisture or oil contained in the gas to be ventilated. A ventilation device and a ventilation method can be realized.
Incidentally, the coefficients a and b in Expression 1 are coefficients that are calculated and determined in advance based on, for example, the exhaust flow rate Q and the differential pressure ΔP acquired for each of the plurality of outputs of the pressure feeding unit.

  As the above-described ventilation device, it is preferable that the control device calculates the exhaust gas flow rate Q based on the equation 1 regardless of the temperature T measured by the temperature measuring means.

Additional features of the ventilation system
The temperature measuring means is provided inside an outer casing disposed on the upstream side of the air blowing means in the gas flow part,
The outer casing includes an opening that communicates the inside thereof with the gas flow region of the gas flow part, and the opening is downstream in the gas flow direction of the gas flow part. It is in the point opening toward.

  According to the above characteristic configuration, the temperature measuring means can measure the temperature of the gas flowing through the gas flow-through portion substantially well, but suppresses contact with the gas flow flowing through the gas flow-through portion. Therefore, even when moisture or oil is contained in the gas, the moisture or oil can be prevented from adhering to the temperature measuring means.

Additional features of the ventilation system
The first pressure measuring means is provided in an outer casing disposed on the upstream side of the air blowing means in the gas flow part,
The outer casing includes an opening that communicates the inside thereof with the gas flow region of the gas flow part, and the opening is downstream in the gas flow direction of the gas flow part. It is in the point opening toward.

  According to the above characteristic configuration, the first pressure measurement means can measure the pressure of the gas flowing through the gas flow-through portion substantially well, but is in contact with the gas flow flowing through the gas flow-through portion. Therefore, even when moisture or oil is contained in the gas, it is possible to suppress the moisture or oil from adhering to the first pressure measuring means.

In the ventilator described so far, the reference temperature T ₀ is more preferably 273.15K.

Schematic configuration diagram of ventilator A graph showing the exhaust flow rate calculated based on the relational expression and the differential pressure that are not corrected at the reference temperature A graph showing the difference between the calculated value and the actually measured value in FIG. 2 at each differential pressure. A graph showing the exhaust flow rate calculated based on the relational expression for correcting at the reference temperature and the differential pressure, and the actual measurement value

  The ventilation device 100 according to the embodiment of the present invention does not depend on the shape or installation location of the device, and can know the exhaust flow rate well without being affected by moisture or oil contained in the gas to be ventilated. The present invention relates to a ventilation device and a calculation method.

  The ventilator 100 is a ventilator that exhausts the gas in the ventilation target area from the ventilation target area to the outside of the ventilation target area, and is provided in, for example, a kitchen or a kitchen as the ventilation target area. The ventilator 100 discharges, for example, combustion gas E (an example of gas) generated by combustion of a burner unit 11 provided in a gas stove 10 provided in a kitchen, a kitchen, or the like, outside the ventilation target area. It is. The ventilator 100 includes an exhaust hood 20 provided above the gas stove 10, and a gas in a ventilation target area taken in from the exhaust hood 20 (when the burner unit 11 is operating, a high-temperature combustion gas E, When the burner unit 11 is not in operation, the exhaust fan F (an example of a blowing unit) that pumps the exhaust gas E) outside the ventilation target area, and the exhaust fan F based on the ON / OFF operation of the operation unit in the operation unit (not shown) A control device C that performs switching control for switching between stop and operation is provided. In addition, the said control apparatus C carries out change control of the rotation speed at the time of the driving | operation of the exhaust fan F. FIG.

Further, in the ventilation device 100, as various sensors, the gas flow portion 22 that guides the gas in the ventilation target region to the outside of the ventilation target region, and the gas flow in the portion where the gas does not flow on the upstream side of the exhaust fan F. A temperature sensor S2 (an example of a temperature measurement unit) that includes a first pressure sensor S1 (an example of a first pressure measurement unit) that measures a first pressure as a static pressure of the unit 22 and that measures a temperature T of the gas flow unit 22 ), And a second pressure sensor S3 (an example of second pressure measuring means) that measures a second pressure that is a pressure in the ventilation target area.
When the gas stove 10 is provided in the ventilation target area and the combustion apparatus E is configured to exhaust the combustion gas E of the burner portion 11 of the gas stove 10 as in the embodiment, the gas including water and oil is exhausted. Therefore, the gas containing the moisture and oil is passed through the gas flow part 22 where the first pressure sensor S1 and the temperature sensor S2 are provided, and the moisture is supplied to the first pressure sensor S1 and the temperature sensor S2. There is a possibility that problems such as adhesion of oil and oil, deterioration of the sensor, and deterioration of measurement accuracy may occur.
Therefore, in the present embodiment, the first pressure sensor S1 and the temperature sensor S2 are provided inside the outer casing 23 disposed on the upstream side of the exhaust fan F in the gas flow portion 22, The outer casing 23 is provided with an opening 25 that communicates the inside with the gas flow region of the gas flow portion 22. The opening direction of the opening 25 is a direction downstream from the direction of the gas flow in the gas flow portion 22 from the direction perpendicular to the gas flow direction in the gas flow portion 22.
With this configuration, it is possible to prevent a large amount of gas from entering the inside of the enclosure 23, and even when the gas contains moisture or oil, moisture or oil is contained in the first pressure sensor S <b> 1 and the temperature sensor S <b> 2. Adhesion can be well prevented. Note that the pressure of the first pressure sensor S <b> 1 measured in this way is the static pressure of the gas in the gas flow part 22.

  The inventors have intensively studied to determine that the exhaust flow rate Q is the absolute difference between the first pressure measured by the first pressure sensor S1 and the second pressure measured by the second pressure sensor S3. It was found that the value can be calculated based on the differential pressure ΔP, which is a value, and the following formula 5.

Q = c × ΔP ^d (Formula 5)

In FIG. 2, for each differential pressure ΔP, the exhaust flow rate Q when the burner portion 11 of the gas stove 10 is in an operating state (“calculated value with device operation” in FIG. 2) and the burner portion 11 of the gas stove 10 are not The exhaust gas flow rate Q (in FIG. 2, “calculated value without equipment operation”) when in an operating state is shown.
An approximate expression for calculating the exhaust flow rate Q when the burner unit 11 is in operation is a known exhaust flow rate Q shown in the following [Table 1] and the value of the differential pressure ΔP at the exhaust flow rate Q is known. The coefficient c is 46.8964, and the multiplier d is 0.4791.
Similarly, the approximate expression for calculating the exhaust flow rate Q when the burner unit 11 is in the non-operating state is the following different exhaust flow rate Q and the value of the differential pressure ΔP at the exhaust flow rate Q shown in Table 2 below. The coefficient c is 36.7656 and the multiplier d is 0.5074.
Incidentally, the inverter value (Hz) in [Table 1] and [Table 2] is the frequency of the drive voltage to the exhaust fan F and is a value substantially proportional to the output of the exhaust fan F. Moreover, the value in each inverter value (Hz) is an average value of the calculation result of multiple times (in this embodiment, 2 times). FIG. 3 is a graph showing the difference between the measured value (actual value) and the calculated value of the exhaust flow rate Q.

  As shown in the graph of FIG. 2 and the coefficient described above, Expression 5 for calculating the exhaust gas flow rate Q when the burner unit 11 is in the operating state, and exhaust when the burner unit 11 is in the non-operating state. This is an expression different from Expression 5 for calculating the flow rate Q. That is, when the exhaust gas flow rate Q is calculated based on the above equation 5, there arises a problem that it must be derived by equation 5 having a different coefficient and multiplier for each gas temperature T.

The inventors consider that this is because the exhaust flow rate Q depends on the gas temperature T, and the differential pressure ΔP also depends on the gas temperature T, and the exhaust at the reference temperature T ₀ is considered. The flow rate Q ₀ and the exhaust flow rate Q at the temperature T have the relationship of the following formula 3, and the differential pressure ΔP _{0 at the} reference temperature T _{0 and} the differential pressure ΔP at the temperature T have the relationship of the following formula 4. It has been found that the exhaust flow rate Q _{0 at} the reference temperature T ₀ (for example, 273.15 K) and the differential pressure ΔP ₀ have the relationship of the following formula 2.

Q ₀ = a × ΔP ₀ ^b (Formula 2)

Q ₀ = (T ₀ + T) / T ₀ × Q (Formula 3)

ΔP ₀ = (T ₀ + T) / T ₀ × ΔP (Formula 4)

  And it discovered that the following formula 1 obtained by substituting the formula 3 and the formula 4 into the formula 2 can calculate the exhaust flow rate Q with the same formula even when the temperature T is different. .

Q = a × (T ₀ / (T ₀ + T)) × ((T ₀ + T) / T ₀ × ΔP) ^b (Formula 1)

And when T ₀ is set to 273.15K and the burner part 11 of the gas stove 10 is in the operating state, the differential pressure ΔP in Table 1, the temperature T of the gas flow part 22, the exhaust flow rate Q, and the burner of the gas stove 10 Based on the differential pressure ΔP in Table 2 when the section 11 is in the non-operating state, the temperature T of the gas flow section 22, and the exhaust flow rate Q, the values of the coefficient a and the multiplier b in Equation 1 are calculated. The coefficient a is 48.13319 and the multiplier b is 0.478865, which is substantially the same value when the burner unit 11 is in the operating state and in the non-operating state.
That is, even when the gas temperature T is different, the new knowledge that the exhaust flow rate Q can be calculated by the single equation 1 was obtained.

Based on the above knowledge, in the ventilation device 100 of the present application, the control device C includes the temperature T measured by the temperature sensor S2, the first pressure measured by the first pressure sensor S1, and the second. The second pressure measured by the pressure sensor S3 is received, and these values, the reference temperature T ₀ , the coefficient a, the multiplier b, and the above-described equation 1 are stored in advance in a storage unit (not shown). The exhaust flow rate Q is calculated based on the above, and the rotational speed of the exhaust fan F is controlled so that the calculated exhaust flow rate Q becomes a desired value.

Incidentally, Table 3 and Table 4 show the calculated exhaust gas flow rate Q, the actually measured exhaust gas flow rate Q, and the ratio of the difference between them to the exhaust gas flow rate Q (actually measured value) according to the above equation 1. Incidentally, [Table 3] is a value when the burner unit 11 is in an operating state, and [Table 4] is a value when the burner unit 11 is in an inoperative state.
As can be seen from [Table 3] and [Table 4], the ratio of the difference to the exhaust flow rate Q (actually measured value) is 5.3% at the maximum, and it can be said that there is sufficient accuracy.

[Another embodiment]
(1) In the other embodiment, the ventilator 100 has shown an example in which equipment for changing the temperature T of the gas such as the gas stove 10 is provided in the ventilation target region.
However, the ventilator 100 according to the present application performs well even in an environment where a gas stove or the like is not provided in the ventilation target area.
That is, you may provide the ventilation apparatus 100 which concerns on this application with respect to the environment where the gas temperature T of a ventilation object area | region does not change a lot.

(2) In the above embodiment, an average value is adopted for parameters such as the acquired differential pressure ΔP for each exhaust flow Q when deriving the coefficient a and the multiplier b of Equation 1 for calculating the exhaust flow Q. However, a single value may be adopted instead of the average value.

(3) In the above embodiment, the reference temperature T ₀ is 273.15 K, but it may be a temperature other than this temperature.

  The configuration disclosed in the above embodiment (including another embodiment, the same shall apply hereinafter) can be applied in combination with the configuration disclosed in the other embodiment, as long as no contradiction occurs. The embodiment disclosed in this specification is an exemplification, and the embodiment of the present invention is not limited to this. The embodiment can be appropriately modified without departing from the object of the present invention.

  The ventilation device and calculation method of the present invention do not depend on the shape of the device and the installation location of the device, and know the exhaust flow rate well without being affected by moisture or oil contained in the ventilated gas. It can be effectively used as a ventilation device that can perform the calculation and a calculation method.

22: Gas flow part 23: Enclosure housing 25: Opening part 100: Ventilation device C: Control device E: Combustion gas (gas)
E: exhaust gas (gas)
F: the exhaust fan Q: flow rate of the exhaust gas S1: first pressure sensor S2: temperature sensor S3: second pressure sensor T: Temperature T _0: a reference temperature a: coefficient b: Multiplier [Delta] P: differential pressure

Claims (6)

A ventilation device that exhausts gas in a ventilation target area from the ventilation target area to the outside of the ventilation target area,
A blowing means for pumping the gas in the ventilation target area from the ventilation target area to the outside of the ventilation target area;
In the gas flow part for guiding the gas in the ventilation target area to the outside of the ventilation target area, the first pressure measurement means for measuring the first pressure and the temperature at the portion where the gas does not flow on the upstream side of the blowing means, Temperature measuring means for measuring;
Second pressure measuring means for measuring a second pressure in the ventilation target area;
Based on the temperature T measured by the temperature measuring means, the differential pressure ΔP that is the absolute value of the difference between the first pressure and the second pressure, the specific reference temperature T _0, and the following formula 1. A ventilator comprising a control device for calculating the exhaust flow rate Q.
Q = a × (T ₀ / (T ₀ + T)) × ((T ₀ + T) / T ₀ × ΔP) ^b (Formula 1)
However, a and b are constants determined in advance and stored in the control device.   2. The ventilation device according to claim 1, wherein the control device calculates an exhaust gas flow rate Q based on the formula 1 regardless of the temperature T measured by the temperature measuring means. The temperature measuring means is provided inside an outer casing disposed on the upstream side of the air blowing means in the gas flow part,
The outer casing includes an opening that communicates the inside thereof with the gas flow region of the gas flow part, and the opening is downstream in the gas flow direction of the gas flow part. The ventilator according to claim 1 or 2, wherein the ventilator is open. The first pressure measuring means is provided in an outer casing disposed on the upstream side of the air blowing means in the gas flow part,
The outer casing includes an opening that communicates the inside thereof with the gas flow region of the gas flow part, and the opening is downstream in the gas flow direction of the gas flow part. The ventilator according to any one of claims 1 to 3, wherein the ventilator is open. The reference temperature T _0, the ventilating device according to any one of claims 1 to 4 is 273.15 K. A method for calculating an exhaust flow rate for discharging the gas in the ventilation target area from the ventilation target area to the outside of the ventilation target area,
In the gas flow part that guides the gas in the ventilation target area to the outside of the ventilation target area, the first pressure and the ventilation target in a part where the gas does not flow on the upstream side of the blowing means provided in the gas flow part An exhaust gas flow rate calculation method for calculating an exhaust gas flow rate Q based on a differential pressure ΔP that is an absolute value of a difference from a second pressure in a region, a specific reference temperature T _0, and the following formula 1.
Q = a × (T ₀ / (T ₀ + T)) × ((T ₀ + T) / T ₀ × ΔP) ^b (Formula 1)
However, a and b are constants determined and stored in advance.

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