JPH0441267B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an improvement in a drive control system for a rotor of a total heat exchanger that recovers exhaust heat from a living room based on the difference in heat quantity between indoors and outdoors.

[Technical background of the invention and its problems] In general, total heat exchangers were initially often equipped with a bypass damper to avoid pressure loss due to the rotor during outdoor air cooling, but in recent years, the installation area has become larger. Due to this and the high initial cost, there are an increasing number of types that do not have a bypass damper.

FIG. 5 shows a conventional control device having this kind of total heat exchanger. 6, and an exhaust sensor 7, and is controlled by a total heat exchanger controller 12 having an input section 8, a calculation section 9, an outside air cooling determination section 10, and an output section 11, and is used during cooling in midsummer and heating in midwinter. When the living room 13 is used, an exhaust heat recovery operation is performed in which the air supply/exhaust fans 2 and 3 and the rotor 5 are operated simultaneously.

In this case, when the exhaust gas from the living room 13 passes through the heat storage material 4 which also serves as a moisture storage material, the amount of heat it retains is absorbed.
The amount of heat absorbed by the heat storage material 4 is radiated on the air supply side by the rotation of the rotor 5.

By the way, the load on the living room 13 is composed of the internal heat generated by humans and machines that generate heat throughout the year, and the external wall load and ventilation load whose heat flow direction changes depending on the season. In regions where there are changes, it is possible to offset internal heat generation with ventilation load during the intermediate period between the cooling and heating periods. Outside air cooling utilizes this and uses outside air as a cooling heat source by stopping the rotor 5 while operating the air supply and exhaust fans 2 and 3 of the total heat exchanger 1.

During this outside air cooling, the outside air is generally not in an appropriate state, so
As shown in the figure, an exhaust damper 14, an air supply damper 1
5, return air damper 16, and their interlocking mechanism 1
The amount of outside air is controlled by the outside air cooling damper 18 having the number 7 so that the desired outside air mixture ratio is achieved according to the difference between the room temperature and the set room temperature. This mixed supply air is then supplied to the cold water valve 19 according to the difference between the room temperature and the set room temperature.
A cold water coil 20 controlled by a humidifier 21 and a blower 22 which are also controlled by room humidity.
Air is sent to the living room 13 via an air conditioner 23 having a

The air supplied to the living room 13 absorbs the internal heat generation load and rises in temperature, becomes contaminated due to smoking, etc., and is exhausted to the total heat exchanger 1 side by the air return fan 24.

Note that in FIG. 5, reference numeral 25 is a temperature and humidity sensor.

In the conventional total heat exchanger control device having the above configuration, air is supplied and discharged while the rotor 5 is stopped during outdoor air cooling, so that contaminated exhaust air from the living room 13 passes through only a portion of the heat storage material 4. Therefore, there is a problem in that dust, germs, cigarette smoke, etc. from the living room 13 are concentratedly attached to this air receiving part, and the heat storage material 4 becomes unusable in a short period of time.

[Purpose of the invention]

The present invention was made in view of the current situation, and it is an object of the present invention to provide a total heat exchanger control device that can uniformize contamination of heat storage materials, extend inspection and replacement cycles, and reduce maintenance costs.

[Summary of the invention]

The present invention is characterized in that the amount of contaminants accumulated in the living room during outdoor air cooling is calculated, and the rotor is operated intermittently based on the calculation result to equalize the contamination of the heat storage material.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIG.

In the figure, reference numeral 1 denotes a total heat exchanger that includes an exhaust fan 2, an air supply fan 3 interlocked with the exhaust fan 2, a rotor 5 having a heat storage material 4, an outside air sensor 6, and an exhaust sensor 7. The input section 8, the calculation section 9, the integration section 26, the outside air cooling judgment section 10, the intermittent judgment section 27, the interlocking processing section 28, and the output section 11
It is designed to be controlled by a total heat exchanger controller 12 having a.

At a position adjacent to the total heat exchanger 1, as shown in FIG. 1, an outside air cooling damper 18 whose opening degree is controlled during outside air cooling is installed. The outside air cooling damper 18 includes an exhaust damper 14, a supply air damper 15, a return air damper 16, and an interlocking mechanism 17 for these.
The amount of outside air is adjusted to the desired outside air mixture ratio according to the difference between the room temperature and the set room temperature. The mixed supply air obtained by this outside air cooling damper 18 is sent to a cold water coil 20 that is controlled by a cold water valve 19 according to the difference between the room temperature and the set room temperature, a humidifier 21 that is similarly controlled by the room humidity, and a blower 22. Air conditioner 2 with
3 to the living room 13, and the exhaust air from the living room 13 is exhausted to the total heat exchanger 1 side by the return fan 24.

In FIG. 1, reference numeral 25 indicates a temperature and humidity sensor;
29 is the supply air sensor, t _r is the exhaust temperature, t _a is the outside air temperature, t _s is the supply air temperature, x _r is the exhaust absolute humidity, x _a is the outside air absolute humidity, x _s is the supply air absolute humidity, i _r is exhaust enthalpy, i _a is outside air enthalpy, i _s is supply air enthalpy,
h _r is the exhaust gas relative temperature, h _a is the outside air relative temperature, and h _s is the supply air relative temperature.

Next, the effect will be explained.

The total heat exchanger 1 uses the outside air enthalpy i _a and outside air temperature t a determined by the outside air sensor 6 _and the exhaust temperature (i.e. room temperature) t _r determined by the temperature/humidity sensor 25.
is not within a predetermined range, the exhaust fan 2, the fan 3, and the rotor 5 are driven in conjunction with the usage schedule of the living room 13 to perform heat recovery operation.

Further, when the outside air enthalpy i _a is in a state where outside air cooling is possible, only the air supply/exhaust fans 2 and 3 are linked to the usage schedule of the living room 13, and the rotor 5 is stopped to perform outside air cooling operation.

The operations described above are the same as those of the conventional apparatus, and this embodiment has the following features.

That is, in the total heat exchanger controller 12,
When the measured values of the sensors 6 and 25 and the operating status of related equipment are input to the input unit 8, processing such as smoothing and engineering unit conversion is performed there, and then the calculation unit 9
In this step, absolute humidity and enthalpy are calculated using a known method from temperature and relative humidity.

This calculation result is subjected to the above-mentioned condition judgment in the outside air cooling judgment section 10, and this result is given to the output section 11 via the interlocking processing section 28, and the air supply/exhaust fans 2, 3 and the rotor 5 are sent. It will be done.

In this embodiment, if the outside air cooling determination unit 10 determines that outside air cooling is possible, the absolute humidity difference between the supply and exhaust air of the living room 13 determined via the input unit 8 and the calculation unit 9 x _x − x _s and the mixture ratio r determined from the damper opening degree of the interlocking mechanism 17 of the outside air cooling damper 18, the integrated amount of pollutants is determined as Σ(x _r −x _s )·r by the integrating unit 26, and the integrated amount is If it is determined by the intermittent determination section 27 that
1, and the rotor 5 will move by a predetermined rotation angle.

FIG. 2 shows the operating state in this embodiment, and FIG. 2a shows the state of heat recovery operation, in which the air supply/exhaust fan and rotor are linked with the usage schedule of the room. Note that the outside air cooling damper is set to the minimum intake amount, and the air conditioner is operated for preheating and precooling operation before the schedule for the living room.

FIG. 2b shows the operating state of the conventional device during outside air cooling, in which the rotor remains stopped even if the opening degree of the outside air cooling damper changes.

FIG. 2c shows the operating state during outside air cooling in this embodiment, in which the rotor is operated intermittently at variable intervals determined by the opening degree of the outside air cooling damper.

Next, an algorithm for determining the time width of intermittent operation of the rotor will be explained.

Generally, the amount of pollutants in a living room due to dust and smoking is proportional to the number of people in the living room.

On the other hand, when considering the air conditioning load in a living room divided into a sensible heat section and a latent heat section, the latent heat is mainly caused by human exhalation, and is therefore proportional to the number of people. Sensible heat consists of internal equipment heat generation, human body heat generation, heat transfer from external walls, and external heat intrusion due to opening and closing of doors, etc., and is considered to be the sum of the part due to the influence of outside air and the part due to the occupants.

In this embodiment, attention is paid to the fact that the concentration of pollutants in a living room is proportional to the increase in latent heat of the air conditioning load, and the accumulated amount of pollutants is determined without using any special equipment.

This will be explained below with reference to FIG.

Figure 3 is a hygrodynamic diagram, in which point R (t _r ,
x _r , i _r , h _r ) is the exhaust condition of the living room, and point A (t _a , x _a ,
i _a , h _a ) indicates the state of outside air, and point S (t _s , x _s , i _s , h _s ) indicates the state of supply air.

Exhaust air R from the living room is mixed with outside air by an outside air cooling damper to reach a state at point M, and is further cooled by a chilled water coil to become supply air S. This supply air S is blown into the living room, and is added to the internal sensible heat load (t _r −t _s ) and the latent heat load (x _r −x _s ), returning to the state R again.

Here, the outside air mixture ratio r is (MR/AR),
It is uniquely determined from the damper opening. If the damper opening degree is α, the exhaust ratio, that is, the outside air mixture ratio is r
= f(α).

Therefore, the amount of pollutant accumulated at time θ is ∫
(x _r −x _s )·f(α)dθ, which is proportional to the latent heat load of the living room.

Here, if we express x = g (t, h), the previous equation becomes ∫ (g (t _r , h _r ) - g (t _s , h _s )) f (α) dθ, and the temperature and humidity of the living room The intermittent operation time can be calculated from the supply air temperature and humidity, and the opening degree of the outside air cooling damper.

In addition, when inching the rotor 5, in some cases, the same position of the heat storage material 4 may come to the exhaust air blowing part after one rotation as a result of the inching, but this is due to the continuation of the inching operation. The time adjustment can be manually set using the interlocking processing section 28 shown in FIG. 1, so that the time can be set at an appropriate position during adjustment operation.

Therefore, by inching the rotor 5 at time intervals commensurate with the amount of pollutants discharged when cooling the total heat exchanger 1 with outside air, the contamination of the heat storage material 4 can be uniformized and the number of inspections and replacements can be significantly reduced. .

Moreover, by integrating the operating time of the rotor 5 and the number of inchings during outside air cooling and managing the allowable limit, an appropriate maintenance index can be presented.

In the above embodiment, a case has been described in which the pollution concentration in a living room is estimated by the increment of latent heat load. However, in Japan, where there is a cooling period and a heating period, and outside air cooling is performed in the intermediate period between them, At this time, the external wall load due to the influence of outside air is smaller than the internal heat generation, so it is also possible to approximately use sensible heat load instead of latent heat load. That is, this method reduces the amount of pollutants by ∫
(t _r −t _s )·f(α)dθ. In general building air conditioning systems, supply and exhaust temperatures are often measured for management purposes, so this method does not require the installation of a humidity sensor and can further reduce costs.

Furthermore, there are cases, such as office buildings, where people come and go while the room is in use, but it can be considered almost constant. In this case, the latent heat increase (x _r −x _s )=constant, and the intermittent time can also be determined using ∫f(α)dθ as only the damper opening degree as a variable.

Furthermore, the outside air damper opening degree is proportionally controlled by the deviation Δt between the room temperature _tr and the set room temperature t _s , so it is not the damper opening degree, but ∫f (t _r −t _s ) dθ, that is, the room temperature It can also be controlled by integrating the deviation from the exhaust temperature set value.

However, in this case, since the outside air intake amount control has a limit value of the minimum outside air intake amount, it is necessary to simulate the control of the outside air intake amount controller.

This will be explained below with reference to FIG.

During _outside air cooling, the outside air cooling damper absorbs the difference ₍ t _r
-t _s ), the opening of the cold water valve is set to operate abde before it operates fge.
Note that during heat recovery, it is ABC and only the minimum opening degree is ensured.

On the other hand, there is generally a characteristic between the damper opening degree and the amount of air blown, as shown in FIG. 4b, due to the shape of the damper. Therefore, in this case, the outside air temperature obtained from the outside air sensor 6 for outside air cooling determination is input to the input section 8 of the total heat exchanger controller 12 in FIG.
t _a , the outside air humidity h _a , and the exhaust gas temperature t _r obtained from the temperature/humidity sensor 25 or the exhaust sensor 7 are respectively input, and the calculating section 9 calculates the value shown in FIG. By preparing a table and determining the coefficients, it is possible to easily realize a control device that performs intermittent operation corresponding to the amount of pollution.

〔Effect of the invention〕

As explained above, the present invention calculates the amount of contaminants accumulated in the living room during outdoor air cooling, and operates the rotor intermittently based on the calculation result, so that the contamination of the heat storage material is uniformized and inspected and replaced. The number of times can be significantly reduced.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram showing one embodiment of the present invention, and FIG.
Figure a is a timing chart showing the operation of each part in the heat recovery period, Figure b is a timing chart showing the operation of each part in the outside air cooling period of the conventional device, and Figure c is a timing chart showing the operation of each part in the outside air cooling period of the device shown in Figure 1. A timing chart showing the operation of , Figure 3 is a graph showing changes in the state of air on the psychrometric chart,
Figure 4a is a control diagram of the outside air cooling damper, Figure 4b is a graph showing the relationship between damper opening degree and air flow rate, Figure 4c is
is a conversion diagram for the present invention, and FIG. 5 is a configuration diagram showing a conventional example. 1... Total heat exchanger, 2... Exhaust fan, 3... Air blower, 4... Heat storage material, 5... Rotor, 6... Outside air sensor, 7... Exhaust sensor, 12... Total heat exchanger Controller, 13... Living room, 18... Outside air cooling damper, 23... Air conditioner, 25... Temperature/humidity sensor, 29... Air supply sensor.

Claims (1)

[Scope of Claims] 1. A total heat exchanger having a rotor having a heat storage material, an air supply fan that takes in outside air through the rotor, and an exhaust fan that exhausts air from a living room to the outside through the rotor; an outside air cooling damper that adjusts the mixture of outside air and exhaust gas from a living room during outside air cooling to obtain a predetermined outside air mixture ratio; a calculation means that calculates the amount of accumulated pollutants in the living room; and a rotor for rotating the total heat exchanger. and a drive means for cooling the outside air.
A total heat exchanger control device comprising means for intermittently operating a rotor by a drive means based on the calculation result from the calculation means. 2. A patent claim characterized in that the calculation means consists of a means for detecting latent heat changes in the air supply and exhaust air in the room, a means for detecting an outside air mixture ratio, and a means for calculating the accumulated amount of pollutants in the room based on the outputs of both detection means. Total heat exchanger control device according to scope 1. 3. Claim 1, characterized in that the calculating means comprises means for detecting the exhaust gas temperature of the living room, means for detecting the set room temperature, and means for calculating the accumulated amount of pollutants in the living room based on the outputs of both the detecting means. Total heat exchanger control device as described in Section 1.