JP6656054B2 - Ventilation device and calculation method - Google Patents

Description

  The present invention provides a ventilator for discharging the gas in a ventilation target area from a ventilation target area to outside the ventilation target area, and a method of calculating an exhaust flow rate Q for discharging the gas in the ventilation target area from the ventilation target area to the outside of the ventilation target area. About.

DESCRIPTION OF RELATED ART Conventionally, as a ventilator which discharges the gas of a ventilation target area | region from a ventilation target area | region outside a ventilation target area | region, as shown in patent document 1, the exhaust duct which connects the ventilation target area | region and the outside of a ventilation target area | region, A fan for pumping the air from the ventilation target area to the outside of the ventilation target area via the exhaust duct.
Such a ventilator measures the gas flow rate in the exhaust duct to keep the exhaust flow rate below a predetermined upper limit in order to prevent the exhaust flow rate from becoming too large and increasing the noise while keeping the exhaust flow rate above a predetermined lower limit. The flow rate sensor is provided, and the rotation speed of the fan is controlled based on the measurement value of the flow rate sensor.

JP-A-2015-114617

In the technology disclosed in Patent Document 1, since the airflow sensor is provided in a state where it is exposed to gas flowing through the exhaust duct, for example, when the gas contains moisture, oil, or the like, There has been a problem that the moisture or oil content adheres to the air volume sensor, and the air volume sensor is deteriorated or the measurement accuracy of the air volume sensor is reduced.
In order to avoid such a problem, it is conceivable to provide an airflow sensor at a portion of the exhaust duct where oil and moisture hardly adhere, but the shape of the exhaust duct differs for each ventilation device and each installation location of the device. Therefore, it is necessary to study 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 its purpose is not to depend on the shape of the device and the installation location of the device, and to be affected by moisture and oil contained in the gas to be ventilated. The present invention relates to a ventilator capable of properly knowing the exhaust flow rate and a calculation method.

Ventilation equipment to achieve the above purpose,
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 its characteristic configuration is
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 a gas flow portion that guides the gas in the ventilation target region to the outside of the ventilation target region, at a portion where the gas does not flow on the upstream side of the blowing device, a first pressure measuring unit that measures a first pressure and a temperature. Temperature measuring means for measuring;
A second pressure measuring means for measuring a second pressure of the ventilation target area,
Based on a temperature T measured by the temperature measuring means, a differential pressure ΔP which is an absolute value of a difference between the first pressure and the second pressure, a specific reference temperature T _0, and the following equation 1. And a control device for calculating the exhaust gas flow rate Q.
Q = a × (T ₀ / (T ₀ + T)) × ((T ₀ + T) / T ₀ × ΔP) ^b (Equation 1)
Here, a and b are constants determined in advance and stored in the control device.

Further, a method of calculating the exhaust flow rate to achieve the above object is as follows.
It is a method of calculating the exhaust flow rate of discharging the gas in the ventilation target area from the ventilation target area to the outside of the ventilation target area, and as a characteristic configuration,
In the gas flow portion that guides the gas in the region to be ventilated to the outside of the region to be ventilated, the first pressure at a portion where the gas does not flow upstream of the blowing means provided in the gas flow portion and the ventilation target The point at which the exhaust gas flow rate Q is calculated based on the differential pressure ΔP which is the absolute value of the difference from the second pressure in the region, the temperature T at the site, the specific reference temperature T _0, and the following equation 1. is there.
Q = a × (T ₀ / (T ₀ + T)) × ((T ₀ + T) / T ₀ × ΔP) ^b (Equation 1)
Here, a and b are predetermined and stored constants.

The present inventors have made intensive studies and found that the exhaust flow rate Q by the ventilator is determined by a static pressure as a first pressure measured at a portion where gas does not flow upstream of the blowing means in the gas flow portion, From the differential pressure ΔP with the second pressure in the region to be ventilated and the specific reference temperature T ₀ , it has been found that it can be calculated based on the above (Equation 1) in a state where the actual measured value is highly correlated.
By adopting a configuration for calculating the exhaust flow rate Q as in the above characteristic configuration, it is not necessary to provide a flow sensor for measuring the exhaust flow discharged to the outside of the area to be ventilated by the ventilator. It is possible to appropriately calculate the exhaust flow rate Q without being affected by oil or oil adhesion.
Furthermore, according to the above-mentioned characteristic configuration, for example, a sensor that measures temperature as temperature measuring means, a sensor that measures first pressure as first pressure measuring means, and a sensor that measures second pressure as second pressure measuring means are provided. In other words, the sensor for measuring the temperature may measure the temperature of the gas, and the sensor for measuring the first pressure may measure the static pressure of the gas. It may be provided at a portion where there is no gas flow). In addition, since the sensor for measuring the second pressure measures the pressure in the area to be ventilated, it may be provided at a portion not exposed to the gas flow. That is, according to the above configuration, it is possible to prevent the sensors and the like from adhering to the sensors and the like, such as moisture and oil, thereby deteriorating the sensors and reducing the measurement accuracy of the sensors.

In addition, for example, a ventilation device set at home is often provided above a cooking appliance such as a stove, but in such a configuration, the temperature of gas exhausted by the ventilation device increases the temperature of the cooking appliance. It changes depending on whether or not it is used.
The inventors have derived Equation 1 above as an equation that can derive the exhaust flow rate well even when the temperature of the gas flowing through the gas flow section is different.

The inventors first found that the exhaust gas 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 Expression 2.
Q ₀ = a × ΔP ₀ ^b (Equation 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 equation 3, where 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 (Equation 3)

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

Equation 1 obtained by substituting Equations 3 and 4 into Equation 2 allows the exhaust flow rate Q to be calculated by the same equation even when the temperature T is different.
Thereby, for example, the ventilation device is configured to discharge the exhaust gas from the stove or the like as a gas to the outside of the region to be ventilated, and in a case where the temperature of the exhaust gas as the gas greatly changes depending on whether the stove is used or not. Even so, the exhaust flow rate can be properly calculated by the single equation 1 in a state where the exhaust flow rate is highly correlated with the actually measured value.
That is, according to the above-described characteristic configuration, the exhaust flow rate can be well known without depending on the shape of the device or the installation location of the device, and without being affected by the 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 Equation 1 are coefficients that are calculated and determined in advance based on, for example, the exhaust flow rate Q and the differential pressure ΔP obtained for each of a plurality of outputs of the pumping means.

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

Further features of the ventilation system
The temperature measuring means is provided inside an outer casing arranged on the upstream side of the blowing means in the gas flow portion,
The outer housing includes an opening communicating the inside thereof with the gas flow region of the gas flow portion, and the opening is located downstream in the gas flow direction of the gas flow portion. There is a point that is open toward.

  According to the above-mentioned characteristic configuration, the temperature measuring means can measure the temperature of the gas flowing through the gas flow section substantially satisfactorily, but suppresses contact with the gas flow flowing through the gas flow section. Therefore, even if the gas contains moisture or oil, the moisture or oil can be prevented from adhering to the temperature measuring means.

Further features of the ventilation system
The first pressure measuring means is provided inside an outer casing provided in the gas flow portion on the upstream side of the blowing means,
The outer housing includes an opening communicating the inside thereof with the gas flow region of the gas flow portion, and the opening is located downstream in the gas flow direction of the gas flow portion. There is a point that is open toward.

  According to the above-mentioned characteristic configuration, the first pressure measuring means can measure the pressure of the gas flowing through the gas flow section substantially satisfactorily, and contact the gas flow flowing through the gas flow section. Therefore, even when the gas contains moisture or oil, the moisture or oil can be prevented from adhering to the first pressure measuring means.

For the ventilator described so far, it is more preferable that the reference temperature T ₀ is 273.15K.

Schematic configuration diagram of the ventilation device FIG. 6 is a graph showing an exhaust flow rate calculated based on a relational expression that does not perform correction at a reference temperature and a differential pressure FIG. 4 is a graph showing the difference between the calculated value and the measured value in FIG. 2 at each differential pressure. FIG. 4 is a graph showing an exhaust flow rate calculated based on a relational expression for performing correction at a reference temperature and a differential pressure, and actual measurement values;

  The ventilating apparatus 100 according to the embodiment of the present invention does not depend on the shape or the installation location of the apparatus, and is capable of satisfactorily knowing the exhaust flow rate without being affected by moisture or oil contained in the gas to be ventilated. The present invention relates to a ventilator that can be used and a calculation method.

  The ventilating device 100 is a ventilating device that discharges gas in a region to be ventilated from the region to be ventilated to the outside of the region to be ventilated, and is provided in, for example, a kitchen or a kitchen as the region to be ventilated. The ventilator 100 discharges, for example, a 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 to the outside as a region to be ventilated. It is. The ventilation device 100 includes an exhaust hood 20 provided above the gas stove 10, and a gas in a region to be ventilated taken in from the exhaust hood 20 (a high-temperature combustion gas E when the burner unit 11 is operating, When the burner unit 11 is inactive, the exhaust fan F (an example of a blowing unit) for pumping the exhaust gas E) out of the area to be ventilated, and the exhaust fan F based on ON / OFF operation of a driving operation unit in an operation unit (not shown). A control device C is provided for performing switching control for switching between stop and operation. Note that the control device C changes and controls the rotation speed of the exhaust fan F during operation.

Further, in the ventilating apparatus 100, as various sensors, a gas flow portion 22 that guides the gas in the region to be ventilated to the outside of the region to be ventilated. A first pressure sensor S1 (an example of a first pressure measuring means) for measuring a first pressure as a static pressure of the section 22 and a temperature sensor S2 (an example of a temperature measuring means) for measuring a temperature T of the gas flow section 22; ), And a second pressure sensor S3 (an example of a second pressure measuring unit) that measures a second pressure that is a pressure in the ventilation target area.
As in the present embodiment, when the ventilator 100 adopts an installation mode in which the gas stove 10 is provided in a region to be ventilated and the combustion gas E of the burner unit 11 of the gas stove 10 is exhausted, the gas including moisture and oil is exhausted. That is, the gas containing the moisture and the oil flows through the gas passage portion 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 deterioration of the sensor or deterioration of the measurement accuracy due to the adhesion of oil or oil may occur.
Therefore, in the present embodiment, the first pressure sensor S1 and the temperature sensor S2 are provided inside the outer casing 23 provided on the gas flow portion 22 on the upstream side of the exhaust fan F. The outer casing 23 is provided with an opening 25 that communicates the inside with the gas flow area of the gas flow section 22. The opening direction of the opening 25 is a direction downstream of the gas flow direction of the gas flow portion 22 from the direction perpendicular to the gas flow direction of the gas flow portion 22.
With this configuration, it is possible to prevent a large flow of gas from entering the inside of the outer housing 23, and even when moisture or oil is contained in the gas, the moisture or oil is detected by the first pressure sensor S1 and the temperature sensor S2. Adherence can be satisfactorily prevented. The pressure of the first pressure sensor S1 measured in this manner is the static pressure of the gas in the gas flow section 22.

  Now, the present inventors have made intensive studies and found that the exhaust flow rate Q is the absolute value of the difference between the first pressure measured by the first pressure sensor S1 and the second pressure measured by the second pressure sensor S3. It has been found that it can be calculated based on the differential pressure ΔP which is a value and the following Expression 5.

Q = c × ΔP ^d (Equation 5)

In FIG. 2, for each differential pressure ΔP, the exhaust flow rate Q (“calculated value with device operation” in FIG. 2) when the burner unit 11 of the gas stove 10 is in the operating state, and the burner unit 11 of the gas stove 10 FIG. 2 shows an exhaust flow rate Q (“calculated value without device operation” in FIG. 2) in the operating state.
An approximate expression for calculating the exhaust flow rate Q when the burner unit 11 is in the operating state is as follows: The different exhaust flow rates Q shown in Table 1 below and the value of the differential pressure ΔP at the exhaust flow rate Q are known. It can be derived based on a statistical method, the coefficient c is 46.8964, and the multiplier d is 0.4791.
Similarly, an approximate expression for calculating the exhaust flow rate Q when the burner unit 11 is in the non-operating state is obtained by calculating a different exhaust flow rate Q shown in the following Table 2 and the value of the differential pressure ΔP at the exhaust flow rate Q. The coefficient c is 36.7656, and the multiplier d is 0.5074.
Incidentally, the inverter values (Hz) in [Table 1] and [Table 2] are the frequencies of the drive voltage to the exhaust fan F, and are values that are substantially proportional to the output of the exhaust fan F. Further, the value at each inverter value (Hz) is an average value of the calculation results obtained a plurality of times (two times in this embodiment). FIG. 3 is a graph showing a difference between a measured value (actually measured value) and a calculated value of the exhaust gas flow rate Q.

  As shown in the graph of FIG. 2 and the coefficients described above, Equation 5 for calculating the exhaust gas flow rate Q when the burner unit 11 is in the operating state, and the exhaust gas flow when the burner unit 11 is in the non-operating state. The equation is different from Equation 5 for calculating the flow rate Q. That is, when calculating the exhaust gas flow rate Q based on the above equation 5, a problem arises that the coefficient and the multiplier must be derived for each gas temperature T using the equation 5 which is different.

We, this causes the exhaust flow rate Q are dependent on the temperature T of the gas, even the differential pressure ΔP probably because is dependent on the temperature T of the gas, the exhaust gas at the reference temperature T ₀ The flow rate Q ₀ and the exhaust flow rate Q at the temperature T have the relationship of the following equation 3, and the differential pressure ΔP _{0 at the} reference temperature T _{0 and} the differential pressure ΔP at the temperature T are expressed by the following equation 4. It has been found that the exhaust gas 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 equation 2.

Q ₀ = a × ΔP ₀ ^b (Equation 2)

Q ₀ = (T ₀ + T) / T ₀ × Q (Equation 3)

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

  Then, it has been found that the following equation 1 obtained by substituting the equations 3 and 4 into the equation 2 allows the exhaust flow rate Q to be calculated by the same equation even when the temperature T is different. .

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

When T ₀ is 273.15 K, the differential pressure ΔP in Table 1 when the burner 11 of the gas stove 10 is in the operating state, 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, the temperature T of the gas flow section 22, and the exhaust flow rate Q in Table 2 when the section 11 is in the non-operating state, the values of the coefficient a and the multiplier b of Equation 1 are calculated. , Coefficient a is 48.13319, and 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, a new finding has been obtained that the exhaust gas flow rate Q can be calculated by the single equation 1 even when the gas temperature T is different.

Based on the above findings, in the ventilation device 100 of the present application, the control device C controls 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, the values thereof, the reference temperature T ₀ , the coefficient a, the multiplier b stored in advance in a storage unit (not shown), and the above-described equation (1). , The exhaust flow rate Q is calculated based on the calculated value, and the rotation speed of the exhaust fan F is controlled such that the calculated exhaust flow rate Q becomes a desired value.

Incidentally, Table 3 and Table 4 show the exhaust flow rate Q calculated by the above equation 1, the actually measured exhaust flow rate Q, and the ratio of the difference to the exhaust flow rate Q (actually measured value). Incidentally, [Table 3] is a value when the burner unit 11 is in the operating state, and [Table 4] is a value when the burner unit 11 is in the non-operating state.
As can be seen from Tables 3 and 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 above-described another embodiment, the example in which the ventilation device 100 is provided with equipment for changing the temperature T of the gas such as the gas stove 10 in the region to be ventilated has been described.
However, the ventilating apparatus 100 according to the present application exhibits its function well even in an environment where a gas stove or the like is not provided in a region to be ventilated.
That is, the ventilation device 100 according to the present application may be provided for an environment in which the temperature T of the gas in the ventilation target area does not greatly change.

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

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

  Note that the configuration disclosed in the above-described embodiment (including another embodiment, the same applies hereinafter) can be applied in combination with the configuration disclosed in other embodiments, as long as no contradiction occurs. The embodiment disclosed in the present specification is an exemplification, and the embodiment of the present invention is not limited thereto, and can be appropriately modified without departing from the object of the present invention.

  The ventilation device and the calculation method of the present invention are not dependent on the shape of the device and the installation location of the device, and are capable of properly knowing the exhaust flow rate without being affected by moisture or oil contained in the gas to be ventilated. The present invention can be effectively used as a ventilator and a calculation method that can be used.

22: gas flow portion 23: enclosure 25: opening 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 ventilator that exhausts gas in the ventilation target area from the ventilation target area to the outside of the ventilation target area,
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 a gas flow portion that guides the gas in the ventilation target region to the outside of the ventilation target region, at a portion where the gas does not flow on the upstream side of the blowing device, a first pressure measuring unit that measures a first pressure and a temperature. Temperature measuring means for measuring;
A second pressure measuring means for measuring a second pressure of the ventilation target area,
Based on a temperature T measured by the temperature measuring means, a differential pressure ΔP which is an absolute value of a difference between the first pressure and the second pressure, a specific reference temperature T _0, and the following equation 1. , A ventilation device including a control device for calculating an exhaust flow rate Q.
Q = a × (T ₀ / (T ₀ + T)) × ((T ₀ + T) / T ₀ × ΔP) ^b (Equation 1)
Here, 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 the exhaust gas flow rate Q based on the expression 1 regardless of the temperature T measured by the temperature measurement unit. 3. The temperature measuring means is provided inside an outer casing arranged on the upstream side of the blowing means in the gas flow portion,
The outer housing includes an opening communicating the inside thereof with the gas flow region of the gas flow portion, and the opening is located downstream in the gas flow direction of the gas flow portion. The ventilator according to claim 1, wherein the ventilator is open toward the vehicle. The first pressure measuring means is provided inside an outer casing provided in the gas flow portion on the upstream side of the blowing means,
The outer housing includes an opening communicating the inside thereof with the gas flow region of the gas flow portion, and the opening is located downstream in the gas flow direction of the gas flow portion. The ventilation device according to any one of claims 1 to 3, which is open toward the user. The reference temperature T _0, the ventilating device according to any one of claims 1 to 4 is 273.15 K. A method of calculating the exhaust flow rate to discharge the gas in the ventilation target area from the ventilation target area to the outside of the ventilation target area,
In the gas flow portion that guides the gas in the ventilation target region to the outside of the ventilation target region, the first pressure and the ventilation target in a portion where the gas does not flow upstream of the blowing means provided in the gas flow portion Exhaust flow rate for calculating an exhaust flow rate Q based on the differential pressure ΔP that is the absolute value of the difference from the second pressure in the region, the temperature T at the site, a specific reference temperature T _0, and the following equation 1. Calculation method.
Q = a × (T ₀ / (T ₀ + T)) × ((T ₀ + T) / T ₀ × ΔP) ^b (Equation 1)
Here, a and b are predetermined and stored constants.

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