JP2008298380A - Operating method of building frame thermal storage air-conditioning system and the building frame thermal storage air-conditioning system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an operating method of a building frame thermal storage air-conditioning system and the building frame thermal storage air-conditioning system, capable of suppressing conduction of cold heat to indoor air when the cold heat is stored in a building frame by introducing cold air to an underfloor chamber. <P>SOLUTION: In this operation method of an air-conditioning system 10, cooling air cooled to the temperature lower than room temperature is introduced from an air conditioner 20 to the underfloor chamber 80 formed between a floor panel 70 and a slab 90 to store cold heat in the slab 90, and the cold heat stored in the slab 90 is used to cool the interior 30. Air quantity of the cooling air introduced to the underfloor chamber 80 by the air conditioner 20 during thermal storage in the slab 90 is set smaller than design maximum air quantity of the air conditioner 20. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an operation method of a housing heat storage air conditioning system that uses housing heat storage for indoor cooling and to the housing heat storage air conditioning system, and relates to a technique for preventing the room temperature from excessively decreasing at the end of heat storage.

  In recent years, there has been an increasing demand for power load leveling. As one of the effective measures to respond to this request, building heat storage that uses night electricity to store cold energy in floor slabs, etc., which are building frames, and uses the cold energy for cooling during the day has attracted attention. For example, a frame heat storage technique as disclosed in Patent Document 1 has been proposed.

In Patent Document 1, in floor blowing air conditioning, air cooled in a floor chamber between a floor slab and a floor panel is introduced at night to store the cold heat in the floor slab, and the peak of the air conditioning load during the daytime. Until then, use air at a temperature lower than the floor slab temperature for air conditioning to reduce heat dissipation from the floor slab, and then change the temperature of the air conditioned air above the floor slab temperature when the air conditioning load peaks. A method of operating an air conditioner that can suppress the upper limit of power consumption of the air conditioner by dissipating the cold heat stored in the floor slab and performing indoor air conditioning is disclosed.
Japanese Patent No. 3748494

  By the way, in the operating method of the air conditioner disclosed in Patent Document 1, when cold air is introduced into the underfloor chamber at night and the cold heat is stored in the floor slab, the cold heat is conducted not only to the floor slab but also to the floor panel. For this reason, the indoor air is cooled by the cold heat conducted to the floor panel, and the temperature of the indoor air at the end of the heat storage may be too cold than an appropriate temperature as a living environment.

  The present invention has been made in view of the above points, and a housing capable of suppressing the conduction of cold heat to indoor air when air cooled in the underfloor chamber is introduced to store cold heat in the building housing. It aims at providing the operating method of a thermal storage air conditioning system, and its frame thermal storage air conditioning system.

In order to achieve the above-described object, the present invention reduces the temperature by introducing cooling air cooled to a temperature lower than room temperature from an air conditioner into an underfloor chamber formed between a floor panel and a floor slab. It is an operation method of a housing heat storage air conditioning system that uses the cold energy stored in the floor slab when storing heat in the slab and cooling the room,
The air volume of the cooling air introduced into the underfloor chamber by the air conditioner when storing heat in the floor slab is set to be smaller than the designed maximum air volume of the air conditioner (first invention).

  According to an experiment conducted by the present inventor, when cooling air is introduced into the underfloor chamber, the cooling air introduced into the underfloor chamber moves away from the inlet, and as the wind speed decreases, the lower layer is lower than the upper layer in the underfloor chamber. The measurement result that the wind speed of is relatively faster is obtained. Therefore, if the air volume of the cooling air introduced from the air conditioner into the underfloor chamber is set small, the wind speed flowing through the underfloor chamber is reduced, and the lower wind speed is relatively high.

  That is, according to the operation method of the housing heat storage air conditioning system of the present invention, by setting the air volume of the air conditioner smaller than the design maximum air volume, the speed of the cooling air flowing in the underfloor chamber is lower in the lower layer than in the upper layer. It becomes relatively fast and can effectively store the cold heat of the cooling air in the floor slab, and the conduction amount of the cold heat to the floor panel is also reduced, so that the indoor air can be prevented from being too cold at the end of the heat storage operation. The design maximum air volume indicates an air volume necessary for processing the maximum cooling load in the air-conditioned room.

  According to a second invention, in the first invention, the air volume of the cooling air introduced into the underfloor chamber by the air conditioner during the heat storage is stored in the floor slab within a predetermined time during which the heat is stored. It is characterized by adjusting to such an extent that it can be made to occur.

According to a third aspect, in the first or second aspect, the heat storage operation is performed when nighttime power is applied.
According to the operation method of the housing heat storage air conditioning system of the present invention, the housing heat storage is performed at the time of nighttime power application, and the heat is taken out during the day and used for cooling. Can be reduced, and can contribute to load leveling of power.

According to a fourth invention, in any one of the first to third inventions, an air conditioner including an inverter control fan is used as the air conditioner.
According to the operation method of the frame heat storage air conditioning system of the present invention, as the air volume is reduced, the power consumption of the air conditioner integrated per day including the daytime can also be reduced.

A fifth aspect of the invention is a heat storage operation for storing cold heat in a floor slab by introducing cooling air cooled to a temperature lower than room temperature from an air conditioner into an underfloor chamber formed between the floor panel and the floor slab. It is a housing heat storage air conditioning system that uses the cold heat stored in the floor slab by the heat storage operation when the room is cooled,
The air volume of the cooling air introduced into the underfloor chamber by the air conditioner during the heat storage operation is set to be smaller than the designed maximum air volume of the air conditioner.

  ADVANTAGE OF THE INVENTION According to this invention, when cold air is introduced into the underfloor chamber and the cold energy is stored in the building frame, the operation method of the frame heat storage air conditioning system and the frame heat storage air conditioning system capable of suppressing the conduction of the cold heat to the indoor air. Can provide.

Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic diagram of a floor blowing air-conditioning system 10 for carrying out frame heat storage according to the present embodiment.

  FIG. 1 shows a room 30 in which an air conditioner 20 is installed in a structure for carrying out frame heat storage according to the present embodiment. The room 30 is surrounded by slabs 40 and 90 which are concrete frames of the building.

  A floor panel 70 is provided above the lower slab 90, and an underfloor chamber 80 is formed between the floor panel 70 and the slab 90. The floor panel 70 is provided with a plurality of floor outlets 72 for blowing air from the underfloor chamber 80 into the room 30.

  A ceiling panel 60 is provided below the upper slab 40, and a ceiling back chamber 50 is formed between the ceiling panel 60 and the slab 40. The ceiling panel 60 is provided with a plurality of suction ports 62 for sucking the air in the room 30 into the ceiling back chamber 50.

  The air conditioner 20 includes an inverter-controlled fan 22 and a heat exchanger 24, and introduces conditioned air from the inlet 28 into the underfloor chamber 80 through the air supply duct 26.

  Suction ducts 100 and 110 communicate with the underfloor chamber 80 and the underfloor chamber 50, and air sucked from the underfloor chamber 50 and the underfloor chamber 80 through the suction ducts 100 and 110 is collected by the return air duct 120. Thus, the air is returned to the air conditioner 20.

  Each of the suction ducts 100, 110 is provided with a switching damper 102, 112, which opens and closes the flow path of the air flowing through the suction ducts 100, 110 in accordance with nighttime housing heat storage or daytime air conditioning operation. It can be done.

Next, air conditioning control at night and during the day using these facilities will be described. In this air conditioning control, the appropriate temperature in the room 30 is 26 ° C., and the maximum air volume that can be supplied by the air conditioner 20 is 20 m ³ / (h · m ² ) (the air volume per floor area).

  When heat is stored in the building slab 90 at night, the switching damper 102 of the suction duct 100 is closed, the switching damper 112 of the suction duct 110 is opened, and the air cooled from the air conditioner 20 to the underfloor chamber 80 is cooled. Is introduced.

  The air thus cooled circulates from the air conditioner 20 so as to return to the air conditioner 20 through the underfloor chamber 80, the suction duct 110, and the return air duct 120, and cold air is stored in the slab 90 by the circulation of the cooling air. Is done. In addition, it is preferable to make heat storage at the time of nighttime electric power application.

Here, the temperature of the air supplied by the air conditioner 20 is set to a temperature (for example, 16 ° C.) lower than the room temperature (for example, 26 ° C.) at the start of heat storage, and the air volume is set in the room 30 to be air-conditioned. The air volume is set to be smaller than the air volume necessary for supply (for example, 6 m ³ / (h · m ² ), which is 30% of the design maximum air volume 20 m ³ / (h · m ² ) of the air conditioner).

  FIG. 2 is a graph showing experimental results obtained by measuring wind speeds at two measurement positions at different distances from the inlet when cold air or hot air is introduced into the underfloor chamber. In this experiment, a full-size double floor model in which the height of the underfloor chamber was set to 150 mm was produced and ventilated, and the upper layer in the underfloor chamber at a position Ab of 1600 mm from the inlet and a position Ad of 5200 mm. The wind speed from the bottom to the lower layer was measured. For detailed measurement methods and measurement conditions, refer to Reference 1 (Fujita et al., “Study on floor air-conditioning system, Part 3: Modeling of heat transfer around the underfloor chamber”, Architectural Institute of Japan Proceedings No. 537, 2000. November, pp. 63-70).

  As shown in FIG. 2, the horizontal axis of this graph indicates the wind speed, the vertical axis indicates the distance from the upper surface of the slab 90, and 12 combinations of the temperature in the underfloor chamber 80 at the time of introduction and the temperature of the introduced air are shown. The experimental results are plotted (cold air is indicated by a solid line and hot air is indicated by a broken line).

  Looking at the distribution of the graph in the figure, at the measurement position Ab located close to the introduction port, the distribution from the upper layer to the lower layer in the underfloor chamber is almost the same distribution during cold air supply and hot air supply. Show. On the other hand, at the measurement position Ad located far from the inlet, there is a difference in the wind speed distribution between the cold air and the hot air, and the lower layer is higher than the lower layer when supplying cold air, and the upper layer is lower than the lower layer when supplying hot air. However, the wind speed increases.

  As described above, when the cold air is supplied, the wind speed in the lower layer is relatively higher than that in the upper layer in the underfloor chamber 80 as the wind speed is reduced from the introduction port. Therefore, by setting the air volume of the cooling air introduced from the air conditioner 20 into the underfloor chamber 80 to be small, the wind speed flowing through the underfloor chamber 80 is reduced, and the wind speed in the lower layer is relatively increased.

  On the other hand, when performing daytime indoor cooling, the switching damper 102 of the suction duct 100 is opened, the switching damper 112 of the suction duct 110 is closed, and the floor outlet 72 of the floor panel 70 is opened. Cooling air is introduced into the underfloor chamber 80 from the machine 20. The temperature of the cooling air supplied here is set to a temperature (for example, 19 ° C.) higher than the air supplied at the start of heat storage, and the air volume is adjusted so that the room temperature becomes an appropriate temperature (26 ° C.). Control.

  By doing in this way, the cooling air introduced into the underfloor chamber 80 is cooled by the cold stored in the slab 90 and blown out from the floor outlet 72 into the room 30 as conditioned air. Then, the air blown into the room 30 returns to the air conditioner 20 through the suction port 62, the ceiling back chamber 50, the suction duct 100, and the return air duct 120.

  According to the present embodiment described above, the cooling air flowing into the underfloor chamber 80 is set by setting the air volume of the air introduced into the underfloor chamber 80 during heat storage smaller than the maximum air volume that can be supplied by the air conditioner 20. The air velocity is relatively lower in the lower layer than in the upper layer, and the cold heat of the cooling air can be effectively stored in the slab 90, and the amount of cold conduction to the floor panel 70 is also reduced, thereby completing the heat storage operation. It can alleviate overcooling of indoor air at the time.

  In addition, according to the present embodiment, the body heat storage is performed at the time of nighttime power application, and the power consumption of the air conditioner 20 during the daytime can be reduced by taking out the heat during the daytime and using it for cooling. Can contribute to leveling the load.

  In addition, according to the present embodiment, by using the air conditioner 20 having the inverter control type fan 22, the power of the air conditioner 20 integrated throughout the day including the daytime is reduced as the air volume is reduced. Consumption can also be reduced.

Next, since the simulation for examining the effect by this embodiment was implemented, the result is demonstrated.
FIG. 3 is a simulation model for examining the effect of the operation method of the air conditioning system 10 according to the present embodiment.

  As shown in FIG. 3, the simulation model models the room 30, the floor panel 70, the underfloor chamber 80, the slab 90, and the ceiling back chamber 50. In this simulation, the heat transfer in the vertical direction around the underfloor chamber 80 was calculated using this model.

  Specifically, the temperature at the center position of each layer (Tr, Tp, Tv, Tc, Tb in FIG. 3) and the temperature at the boundary position between the layers (Tpt, Tp0, Tct, Tc0 in the figure) are representative. These representative temperatures at each time were calculated as temperatures. FIG. 4 shows the details of the codes used in the simulation model of FIG. 3 and their physical property values.

  In this simulation, the temperature at the center position of each layer (Tr, Tp, Tv, Tc, Tb in FIG. 3) is calculated by averaging the temperature distribution in the horizontal direction of each layer. Further, for the inside of the slab 90, the slab 90 is further divided into three layers in the vertical direction, the heat transfer for each layer is taken into consideration, and the temperatures (Tc1 to Tc3) at the respective central positions of these three layers are calculated. .

  Further, the temperature of the air supplied from the air conditioner 20 in the underfloor chamber 80, the temperature of the air for calculating the heat exchange amount with the floor panel 70 and the slab 90, and the air blown from the floor outlet 72 into the room 30. The temperature of the air to be discharged is calculated as a one-dimensional flow in the horizontal direction as shown in FIG. 5, and the convective heat transfer coefficient is multiplied by a correction coefficient to match the heat transfer amount in the actual flow property. ing. For detailed calculation methods and conditions, see the above-mentioned document 1. FIG. 6 is a graph showing the relationship between wind speed and convective heat transfer coefficient used in the simulation. As shown in FIG. 6, different values are given for upward and downward heat flow.

  Further, in this simulation, when it is assumed that an air conditioner equipped with an inverter control type fan is used for air conditioning, the power consumption of the fan in a predetermined period can be calculated.

  Using the simulation model as described above, the following three cases were simulated.

First, as Comparative Example 1, it is assumed that heat storage is performed in a floor blowing air-conditioning system that has been conventionally performed, and air of 16 ° C. is supplied from the air conditioner to the under-floor chamber 80 with a maximum air volume of 20 m ³ / (h · m ² ). Therefore, the standard setting was the case of supplying air for 5 hours from 3 am to 8 am at night. Moreover, the case where the air of 19 degreeC which raised the temperature of the comparative example 1 3 degreeC was supplied as the comparative example 2 was set. On the other hand, as an example assuming the operation method of the present embodiment, the air volume of Comparative Example 1 is set to 6 m ³ / (h · m ² ), which is reduced to 30%, and the temperature is the same as that of Comparative Example 16 16 C.

In addition, when simulation is performed in Comparative Example 1, the operation of the housing heat storage in Comparative Example 2 and the example is performed so that the housing heat storage amount is approximately the same as the amount of heat stored in the slab 90 (567 kJ / m ² ). Each time was set. Specifically, in Comparative Example 2, 7.8 hours (0:12 am to 8:00 am, the amount of heat stored in the enclosure at that time is 568 kJ / m ² ), and in the examples, 11.4 hours (from 8:36 pm At 8:00 am, the heat storage amount of the housing at that time was set to 565 kJ / m ² ).

On the other hand, the air conditioning for cooling the room 30 during the daytime (8:00 am to 8:00 pm) is the same control as in Comparative Examples 1 and 2 and the air introduced into the underfloor chamber 80 from the air conditioner. Was fixed at 19 ° C., and the air volume introduced from the air conditioner was adjusted by the following equation (1) so that the room temperature was maintained at 26 ° C. (T _rset ). However, the air volume V (n) introduced into the underfloor chamber 80 is in the range of a minimum of 6 m ³ / (h · m ² ) to a maximum (V _max ) of 20 m ³ / (h · m ² ), and a coefficient η = 5 did.
_{V (n) = V (n} -1) + η · Δt · V max · {T rset - (2 · T r (n-1) -T r (n-2))}
(1)
In the simulation, the calculation step size Δt is set to 0.2 [h], and the calculation is repeatedly performed for 24 hours from midnight to midnight on the next day until the temperatures at midnight and midnight match. The result when the steady state was reached was recorded.

  FIG. 7 is a graph showing the daily change in temperature in each layer according to the simulation result. In the figure, in each case, the temperature (Tb) in the ceiling back chamber 50, the temperature of the air introduced into the underfloor chamber 80 (Ts), the temperature of the air in the floor outlet 72 (Ta), the room temperature (Tr), And the time change of the temperature (Tc2) of the slab center part is shown on the graph.

  As shown in FIG. 7, in the case of the air conditioning control of Comparative Example 1, the room temperature (Tr) at the end of housing heat storage (8 o'clock: at the start of air conditioning) is 23.9 ° C., which is an appropriate temperature (26 ° C. as a living environment). ) Is too cold. On the other hand, in the air conditioning control of Comparative Example 2, the room temperature (Tr) at the same time is 24.1 ° C., which is only 0.2 ° C. higher than that of Comparative Example 1, The decline has not improved much. On the other hand, in the case of the air conditioning control of the example, the room temperature (Tr) at the same time was 24.7 ° C., increased by 0.8 ° C. compared to the case of Comparative Example 1, and the room temperature decrease was alleviated. .

  On the other hand, changes in room temperature (Tr) during the daytime (8:00 am to 8:00 pm) are substantially the same in Comparative Example 1, Comparative Example 2, and Examples.

  FIG. 8 (a) is a table showing the calculation result of the daily power consumption of the air conditioner fan based on the simulation result, and FIG. 8 (b) is a bar graph showing the calculation result of FIG. 8 (a). It is a thing. In each bar in FIG. 4B, the upper hatched portion indicates the power consumption during the heat storage of the chassis, and the lower hatched portion indicates the power consumption during the daytime air conditioning. Consumption is shown by the total length of the bar graph.

As shown in FIG. 8, the power consumption during air conditioning during the daytime is approximately the same as 26.68 to 27.81 [Wh / m ² ] in any of Comparative Examples 1-2 and Examples. . On the other hand, the power consumption at the time of housing heat storage is 24.33 [Wh / m ² ] in the case of the comparative example 1, whereas it is greatly increased to 36.49 [Wh / m ² ] in the case of the comparative example 2. To increase. On the other hand, in the case of an Example, it reduces significantly with 4.03 [Wh / m < ² >].

  As described above, the operation method of the present embodiment that reduces the air volume supplied from the air conditioner during heat storage by the simulation can alleviate overcooling of the room temperature at the end of heat storage by the housing (8 o'clock: at the start of air conditioning). Moreover, the result which can reduce the electric power consumption of the fan of an air conditioner significantly was obtained also at the time of frame heat storage, and one day accumulation, and the effectiveness of the operation method of this embodiment was confirmed.

It is a schematic diagram of floor blowing air-conditioning system 10 which can carry out frame heat storage concerning this embodiment. It is a graph which shows the experimental result which measured the wind speed of two measurement positions from which the distance from an inlet differs when cold wind or warm air was introduce | transduced in the underfloor chamber. It is a simulation model for examining the effect by the operating method of air-conditioning system 10 concerning this embodiment. It is a table | surface which shows the detail of the physical-property value used for simulation. It is a figure which shows the one-dimensional flow of the horizontal direction of the air in the underfloor chamber used for simulation. It is a graph which shows the relationship between the wind speed used for simulation, and a convective heat transfer coefficient. It is a graph which shows the daily change of the temperature in each layer by a simulation result. It is the electric power consumption of the daily integration of the fan of the air conditioner calculated based on the simulation result.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Air conditioning system 20 Air conditioner 22 Fan 24 Heat exchanger 26 Air supply duct 28 Inlet 30 Indoors 40, 90 Slab 50 Ceiling back chamber 60 Ceiling panel 62 Intake port 70 Floor panel 72 Floor outlet 80 Under floor chamber

Claims (5)

When cooling air is stored in the floor slab by introducing cooling air cooled to a temperature lower than room temperature from the air conditioner into the underfloor chamber formed between the floor panel and the floor slab, An operation method of a frame heat storage air conditioning system that uses the cold energy stored in the floor slab,
An operation method for a housing heat storage air conditioning system, wherein an air volume of the cooling air introduced into the underfloor chamber by the air conditioner when storing heat in the floor slab is set smaller than a design maximum air volume of the air conditioner.   Adjusting the air volume of the cooling air introduced into the underfloor chamber by the air conditioner during the heat storage to such an extent that the floor slab can store a predetermined amount of heat within a predetermined time during which the heat is stored. The operation method of the housing thermal storage air conditioning system of Claim 1 to do.   The method of operating an air conditioner according to claim 1 or 2, wherein the heat storage operation is performed when nighttime power is applied.   The operation method of the housing heat storage air conditioning system according to any one of claims 1 to 3, wherein an air conditioner including an inverter control type fan is used as the air conditioner. It has a function to perform a heat storage operation to store cold heat in the floor slab by introducing cooling air cooled to a temperature lower than room temperature from the air conditioner into the underfloor chamber formed between the floor panel and the floor slab. The housing heat storage air-conditioning system uses the cold energy stored in the floor slab by the heat storage operation when cooling the room,
An enclosure heat storage air conditioning system, wherein an air volume of the cooling air introduced into the underfloor chamber by the air conditioner during the heat storage operation is set smaller than a design maximum air volume of the air conditioner.

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