JP3653398B2 - Fine fog cooling control method and apparatus for cultivation house - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention performs forced ventilation (takes in and discharges outside air) through a fan in a room, and sprays raw water selected from water, liquid fertilizer, or medicine into the airflow for ventilation in the form of fine mist. Thus, the present invention relates to a fine fog cooling control method for a cultivation house and an apparatus thereof for evaporating and cooling the entire room to perform humidification, cooling, fertilizer or chemical spraying on the house cultivation crop.
[0002]
[Prior art]
In the cultivation of crops in this type of cultivation house, the indoor temperature becomes higher than the outside air temperature in a high temperature period such as summer, and this is a major obstacle to the annual cultivation of crops. In particular, crops with poor heat resistance are seriously damaged, and it is necessary to cool the room in order to enable crop cultivation in the high temperature season such as summer. A certain amount of cooling effect can be expected by performing natural ventilation by opening the skylights and side windows of the cultivation house or by operating a ventilation fan, but in the case of cooling only with ventilation, the room temperature is theoretically kept below the outside temperature. It cannot be made and anniversary cultivation cannot be made possible.
[0003]
Therefore, a ventilation fan for forcibly ventilating the room is attached to the cultivation house, and a fine air-conditioning system equipped with a plurality of injection nozzles for injecting raw water into the airflow for the ventilation in the form of fine mist is injected from the nozzle. The applicant previously proposed a fine fog cooling device for a cultivation house that cools the entire room by removing the heat of vaporization when the generated fine fog evaporates from the room air and cooling the air. Yes.
[0004]
[Problems to be solved by the invention]
By the way, in the fine fog cooling device for cultivation house previously proposed by the present applicant, in order to enable year-round cultivation, a predetermined cooling effect can be obtained even under the strongest solar radiation intensity in midsummer when the outdoor temperature is the highest. The capacity was set so that it could be demonstrated. However, in this case, it is not only difficult to optimally manage the room temperature and humidity during cloudy weather or during cooling from May to June or from September to October, but when the cooling load is small, the ventilation fan and fine fog cooling are used. There was a problem in that useless power was consumed to operate the equipment, and running costs were high.
[0005]
The present invention has been made in view of the above circumstances, and wasteful consumption of power is saved by appropriately controlling the ventilation fan and fine fog cooling equipment according to the cooling load such as the amount of solar radiation, the outside air temperature, and the outside air humidity. It is an object of the present invention to provide a fine fog cooling control method for cultivation house and an apparatus thereof that can exhibit the cooling effect that enables year-round cultivation while reducing the running cost.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, a fine fog cooling control method for a cultivation house according to the present invention includes a ventilation fan for forcibly ventilating a room and a raw water selected from water, liquid fertilizer, or medicine for the ventilation airflow. Measure the room temperature, room humidity, outside air temperature, outside air humidity and solar radiation amount of the cultivation house equipped with a fine fog cooling facility that evaporates and cools the whole room by evaporating cooling. By setting the value, the fine mist injection amount and the ventilation amount for the target cooling temperature / humidity are set, and when the measured room temperature exceeds the ventilation start temperature, the ventilation fan is operated at the set ventilation amount to perform cooling by forced ventilation. When the measurement room temperature falls below the ventilation stop temperature, the ventilation fan stops operating.On the other hand, when the measurement room temperature rises above the fine fog cooling start temperature higher than the ventilation start temperature, The fine fog cooling facility is operated at the set fine spray amount to cool the room, and the measurement room temperature is lower than the fine fog cooling stop temperature higher than the above ventilation stop temperature or / and the measurement room humidity is fine fog stop When the humidity falls below, the operation of the fine fog cooling equipment is stopped.
[0007]
Further, in order to achieve the same object as described above, the fine fog cooling control device for cultivation house according to the present invention is disposed in the cultivation house and a ventilation fan for forcibly ventilating the room, and disposed in the cultivation house, A plurality of injection nozzles for injecting raw water into a fine mist form selected from water, liquid fertilizer or chemicals for forced ventilation air flow, a pressure pump for supplying raw water to these injection nozzles, and driving thereof Fine fog cooling equipment equipped with a motor, indoor temperature of the cultivation house, indoor humidity, outside air temperature, temperature and humidity measuring means for measuring the outside air humidity, solar radiation amount measuring means for measuring the amount of solar radiation outside, and each of the above Calorie calculating means for calculating the amount of heat in the cultivation house from the measurement value by the measuring means, the amount of heat calculated by the heat amount calculating means, the indoor temperature of the cultivation house detected by the temperature and humidity measuring means, the room The setting air temperature, the outside air temperature, the outside air humidity, and the calculation means to set the fine mist injection amount and the ventilation amount for the target cooling temperature and humidity, and the indoor temperature measured by the indoor temperature measuring means is higher than the ventilation start temperature. The ventilation fan is operated at the set ventilation volume to cool it with forced ventilation, and when the measured room temperature falls below the ventilation stop temperature, the ventilation fan is stopped while the indoor temperature When the measurement room temperature measured by the measuring means is equal to or higher than the fine fog cooling start temperature higher than the ventilation start temperature, the fine fog cooling equipment is operated with the set fine spray amount to cool the room, and the measurement room temperature When the temperature is below the fine fog cooling stop temperature higher than the ventilation stop temperature or / and the measurement room humidity is below the fine fog cooling stop humidity, the ventilation flow is set to stop the operation of the fine fog cooling equipment. And it is characterized in that the operation of the emissions and fogging cooling equipment and control means for automatically controlling.
[0008]
According to the present invention having the above-described configuration, the fine mist injection amount and the ventilation amount for the target cooling temperature / humidity are set by calculating the indoor temperature / humidity of the cultivation house, the outside air temperature / humidity and the amount of heat in the cultivation house. If the actual room temperature is within the range of ventilation cooling that can keep the room at the target cooling temperature even with forced ventilation alone, operate the ventilation fan at the set ventilation volume above the ventilation start temperature, and below the ventilation stop temperature. Ventilation cooling is performed by operating control of the ventilation fan alone, such as stopping the operation. When the actual room temperature / humidity rises to the required range for fine fog cooling where the room cannot be maintained at the target cooling temperature / humidity by forced ventilation alone, the fine fog cooling equipment is set at a temperature higher than the fine fog cooling start temperature. Ventilation and fine fog combined cooling is performed by controlling the operation of the fine fog cooling equipment, such as operating at a fog spray amount and stopping at or below the fine fog cooling stop temperature or / and the measurement room humidity being below the fine fog cooling stop humidity. It is.
[0009]
By appropriately controlling the ventilation fan and fine fog cooling equipment according to changes in the room temperature and humidity as described above and corresponding to the outside air temperature, humidity and heat quantity at that time, the ventilation fan and fine fog cooling equipment It is possible to always manage the room at the optimum temperature and humidity for crop cultivation while reducing the running cost by eliminating unnecessary consumption of the driving power.
[0010]
In the fine fog cooling control method and apparatus for cultivation house as described above, as described in claim 2 and claim 4, the operation speed of the ventilation fan when the room temperature becomes equal to or higher than the ventilation start temperature is controlled. By making the forced ventilation amount adjustable, it is possible to further reduce the waste of power consumption required for the operation of the ventilation fan.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic perspective view of a cultivation house to which the present invention is applied. A ventilation fan 2 is attached to one of the openings 1a and 1b facing each other in the depth direction of the cultivation house 1, and an intake port 3 is formed on the other, so that the ventilation fan 2 is operated. Thus, the air flow in the direction of arrow a is generated in the room 1R of the cultivation house 1 so that the room 1R is forcibly ventilated. Near the ceiling of the room 1R of the cultivation house 1, a plurality of header pipes 5 with a large number of spray nozzles 4 for spraying raw water upward and in a fine mist are arranged and fixed. It is connected to the pressurizing unit 7 through the pipe 6 (see FIG. 2), and the fine water vapor evaporates by injecting raw water from each jet nozzle 4 into the fine air in the air flow for ventilation in the room 1R. The entire interior of the room 1R is uniformly cooled by cooling the air by removing the heat of vaporization from the room air.
[0012]
As shown in FIG. 2, the pressurizing unit 7 includes a pressurizing pump 8 to which one end of the water supply pipe 6 is connected, a variable speed motor 9 that drives the pressurizing pump 8, and a suction port portion of the pressurizing pump 8. Consists of a raw water tank 11 that is open-connected through a pipe 10, and the pressurizing unit 7 and the spray nozzle 4 constitute a fine fog cooling facility 12. The fine fog cooling system 12 is configured to open and close a plurality of injection control valves 13 respectively interposed at connection points between the water supply pipe 6 connecting the plurality of header pipes 5 to the pressurizing unit 7 and the header pipes 5. The fine mist injection amount can be adjusted by variable control of the operating speed of the pressurizing pump 8 by the variable speed motor 9. Further, the ventilation fan 2 is directly connected to a variable speed motor 14 so that a constant forced ventilation amount can be obtained by full speed operation accompanying the operation of the motor 14.
[0013]
A control device (controller) 15 is provided for automatically operating the cooling temperature and humidity of the room 1R by outputting operation control signals to the variable speed motors 9, 14 and the plurality of injection control valves 13. The control device 15 is composed of a microcomputer, and is installed in a suitable place in the room 1R of the cultivation house 1 and is installed outside the cultivation house 1 with a temperature sensor 16 and a dry / wet bulb type humidity sensor 17 for measuring the room temperature and the room humidity. A temperature sensor 18, a humidity sensor 19 and a pyranometer 20 for measuring the outside air temperature and the outside air humidity are connected to each other. The measured values of the sensors 16 to 19, the measured value of the pyranometer 20, the house area, and the solar transmittance. A function of setting the amount of fine mist injection and ventilation with respect to the target cooling temperature / humidity by calculating the amount of indoor heat calculated from the above, and the ventilation fan according to the change in the temperature measured by the temperature sensor 16 2 and the control of automatically controlling the cooling temperature and humidity of the indoor 1R by automatically controlling the operation of the fine fog cooling equipment 12.
[0014]
Next, the cooling control operation | movement by the fine fog cooling control apparatus for cultivation houses of the said structure is demonstrated with reference to the flowchart of FIG.
Prior to the start of the cooling control operation, the control device 15 includes the indoor temperature measured by the temperature sensors 16 and 18 and the humidity sensors 17 and 19, the outdoor air temperature, the indoor humidity, the outdoor air humidity, the amount of solar radiation measured by the solarimeter 20, and The amount of heat calculated from the known house area and solar transmittance is input (step S21), and the fine mist injection amount xe and the ventilation amount Q for the target cooling temperature t2 and relative humidity φ2 are set by calculating these input values. (Step S22). The basic equations for these operations are as follows.
[0015]
t2 = (i2-597.3 × x3) / (0.24 + 0.441 × x3)
i2: House room enthalpy (kcal / kg)
i2 = ia + i1
i1: Open air enthalpy (kcal / kg)
i1 = 0.24t1 × 34 + (597.3 + 0.441t1) × 1
t1: Outside air temperature (° C)
x3: Absolute humidity during injection (kg / kg ')
x3 = x1 + x2 + xe
x1: Open air absolute humidity (kg / kg ')
x2: Indoor evapotranspiration (kg / kg ')
xe: fine mist injection amount (kg / kg ')
ia: Additional enthalpy during ventilation (kcal / kg)
ia = Sq1 / G
Sq1: heat amount in house due to solar radiation (kcal / min.)
Sq1 = Sq × A × th
Sq: Solar radiation (kcal / m ² · h)
A: House area (m ² )
th: Solar radiation transmittance G: Ventilation flow rate (kg '/ min.)
G = Q / v1
Q: Ventilation rate (m ³ / min.)
v1: Specific volume of outside air (m ³ / kg ′)
v1 = 0.0045 (x1 + 0.622) (273 + t1)
φ2 = x3 / xs × 100
xs: absolute saturation humidity at temperature t2 (kg / kg ')
Note that kg ′ represents air mass.
[0016]
Further, the ventilation amount Q, the spray amount q, and the relative humidity φ2 at the time of ventilation are calculated as follows.
(1) Calculation of ventilation volume during ventilation ・ Calculation of Sq1 (house heat quantity) from Sq (irradiation amount) ・ Calculation of outside air enthalpy i1 from outside air temperature t1 and outside air relative humidity (absolute humidity x1) ・ From target cooling temperature t2 Calculation of ventilation rate Q = Sq1 × v1 / ia (m ³ / min.)
v1: outside air specific volume ia: additional enthalpy (2) calculation of spray amount, calculation of indoor enthalpy i2 during ventilation, calculation of absolute humidity xe by injection amount from target cooling temperature t2, calculation of spray amount q q = xe × Q × v1 (kg / min.)
Q: ventilation volume v1: outside air specific volume (3) calculation of relative humidity, calculation of absolute humidity during injection x3 (x1 + x2 + xe) calculation of relative humidity φ2 φ2 = x3 / xs × 100
xs: saturation absolute humidity at the target cooling temperature t2
Under such setting conditions, it is determined whether or not the room temperature t3 (° C.) measured by the temperature sensor 16 is equal to or higher than the ventilation start temperature t3-1 shown in FIG. 4 (step S23), and the ventilation start temperature. In the case of t3-1 or more, the ventilation fan 2 is operated at the set ventilation amount Q to cool the room 1R by forced ventilation (step S24). In addition, when the ventilation start temperature t3-1 or lower, the ventilation fan 2 remains stopped. Next, it is determined whether or not the room temperature t3 has become equal to or lower than the ventilation stop temperature t3-2 shown in FIG. 4 by the above-described ventilation cooling (step S25). 2 is stopped (step S26).
[0018]
On the other hand, despite the forced ventilation cooling due to the full speed operation of the ventilation fan 2, the indoor temperature t3 continues to rise, and even when the fan capacity reaches the maximum (full speed operation), the fine fog cooling start temperature t3- shown in FIG. When it becomes 3 or more (step S27), the fine fog cooling equipment 12 is operated. In other words, the pressurizing pump 8 is operated via the motor 9 so that the raw water fed through the water supply pipe 6 and the header pipe 5 is sprayed from the spray nozzle 4 into the room 1R in the form of a fine mist at the set injection amount xe. Thus, fine fog cooling is performed (step S28). When the room temperature t3 becomes equal to or lower than the fine fog cooling stop temperature t3-4 shown in FIG. 4 (step S29) or the room humidity becomes equal to or lower than the fine fog cooling stop humidity (step S30). The operation of the fine fog cooling equipment 12 is stopped (step S31). If the room temperature does not become the fine fog cooling stop temperature t3-4 or lower and the fine fog cooling stop humidity or lower in spite of the fine fog cooling, the process returns to step S22 and the fine fog for the target cooling temperature t2 and the relative humidity φ2 is returned. By changing (adjusting) the injection amount xe and the ventilation amount Q and repeating the fine fog cooling in the same steps as above, the room temperature and humidity of the cultivation house 1 can be reduced to the target temperature and the minimum consumption power. Automatic control to humidity. The fine mist injection amount xe is controlled by the injection control valve 13.
[0019]
In the above embodiment, the ventilation fan 2 is described as being operated at full speed via the constant speed motor 14, but the operation speed may be adjustable using a variable speed motor. In this case, by adjusting the operation speed at the time of the above-described ventilation cooling, that is, the forced ventilation amount according to the increase / decrease of the indoor enthalpy, it is possible to further reduce the waste of power consumed for the operation of the ventilation fan 2. .
[0020]
【The invention's effect】
As described above, according to the present invention, ventilation by operating a ventilation fan alone according to changes in room temperature / humidity and corresponding to a cooling load such as the outside air temperature / humidity and the amount of solar radiation (indoor heat quantity) at that time. Since it is possible to appropriately switch and control between cooling and fine fog cooling by parallel operation of fine fog cooling equipment, wasteful consumption of operating power of ventilation fans and fine fog cooling equipment is suppressed as much as possible, and running costs are greatly reduced. It is possible to demonstrate the cooling effect that enables year-round cultivation, especially in the high temperature season such as summer when the room temperature is higher than the outside air temperature. There is an effect that it can be reliably managed.
[0021]
In particular, the power consumption can be further reduced by adopting the configurations of claims 2 and 4.
[Brief description of the drawings]
FIG. 1 is a schematic perspective view of a cultivation house to which the present invention is applied.
FIG. 2 is a schematic configuration diagram of a fine fog cooling device which is a main part of the present invention.
FIG. 3 is a flowchart showing a cooling control operation.
FIG. 4 is a graph showing an example of a change over time in room temperature due to a cooling control operation;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Cultivation house 1R Indoor 2 Ventilation fan 4 Injection nozzle 8 Pressure pump 9, 14 Variable speed motor 12 Fine fog cooling equipment 15 Controller 16, 18 Temperature sensor 17, 19 Humidity sensor

Claims (4)

A fine fan cooling system that evaporates and cools the entire room by injecting raw water selected from water, liquid fertilizer or chemicals into a fine mist for the ventilation fan that forcibly ventilates the room and its air flow for ventilation. Measure the indoor temperature, indoor humidity, outside air temperature, outside air humidity and solar radiation amount of the cultivation house equipped with, and set the fine mist injection amount and ventilation amount for the target cooling temperature and humidity by calculating these measured values,
When the measurement room temperature is equal to or higher than the ventilation start temperature, the ventilation fan is operated at the set ventilation volume to perform cooling by forced ventilation, and when the measurement room temperature is lower than the ventilation stop temperature, the ventilation fan is operated. While stopping the operation of
When the measurement room temperature is equal to or higher than the fine fog cooling start temperature higher than the ventilation start temperature, the fine fog cooling facility is operated at the set fine fog injection amount to cool the room, and the measurement room temperature is When the fine fog cooling stop temperature is higher than the ventilation stop temperature or below and / or when the humidity in the measurement chamber is below the fine fog cooling stop humidity, the operation of the fine fog cooling equipment is stopped. Fog cooling control method. The fine fog cooling control method for a cultivation house according to claim 1, wherein when the measurement room temperature becomes equal to or higher than the ventilation start temperature, the forced ventilation amount is adjusted by controlling the operation speed of the ventilation fan. Ventilation fan attached to the cultivation house to force the room to be ventilated, and the raw water selected from water, liquid fertilizer or chemicals for the forced ventilation airflow in the above cultivation house and sprayed in the form of fine mist A plurality of spray nozzles, a pressurizing pump that feeds raw water to these spray nozzles, and a fine fog cooling facility equipped with a motor for driving the same,
Temperature and humidity measuring means for measuring the indoor temperature, indoor humidity, outside air temperature, outside air humidity of the cultivation house,
Solar radiation measuring means for measuring outdoor solar radiation,
A calorific value calculating means for calculating the calorific value in the cultivation house from the measurement values obtained by the measuring means;
The amount of heat calculated by the heat amount calculation means and the indoor temperature, indoor humidity, outside air temperature, outside air humidity of the cultivation house detected by the temperature and humidity measuring means are input, and fine fog for the target cooling temperature / humidity is calculated by those calculations. Setting means for setting the injection amount and the ventilation amount;
When the indoor temperature measured by the above-mentioned indoor temperature measuring means is equal to or higher than the ventilation start temperature, the ventilation fan is operated at the set ventilation volume to perform cooling by forced ventilation, and the measured indoor temperature is below the ventilation stop temperature. When the operation of the ventilation fan is stopped, the fine air cooling equipment is set when the indoor temperature measured by the indoor temperature measuring means becomes higher than the fine air cooling start temperature higher than the ventilation start temperature. If the measured room temperature is lower than the fine mist cooling stop temperature higher than the ventilation stop temperature or / and the measured indoor humidity is lower than the fine mist cooling stop humidity, the fine mist is cooled. A fine fog cooling control device for a cultivation house, comprising a ventilation fan and a control means for automatically controlling the operation of the fine fog cooling equipment so as to stop the operation of the cooling equipment. 4. The fine fog cooling control device for a cultivation house according to claim 3, wherein the ventilation fan is configured to be capable of adjusting a forced ventilation amount by controlling an operation speed when a measured indoor temperature becomes equal to or higher than a ventilation start temperature. .

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