JP2012092647A - Ventilation amount and temperature prediction system of building - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a system for highly accurately predicting a ventilation condition and a temperature condition inside a building and accurately predicting the condition of indoor air quality together by considering the influence of heat transfer and heat generation in ventilation network calculation.SOLUTION: The system comprises house-by-house data, input means, calculation means and output means. The calculation means considers buoyancy by the difference of the density of air depending on temperature, obtains the ventilation amount of the air in each room, calculates the ventilation amount for each opening by maintaining the total sum of the inflow and outflow of the air in each room at 0, considers the transfer of heat accompanying the air by ventilation, and calculates the temperature of each room by the in/out amount of the heat of the respective rooms with each other. When considering the buoyancy by the difference of the density of the air depending on the temperature in the calculation of the ventilation amount, the temperature obtained from the calculation of the temperature of each room is used for the temperature, and by alternately calculating the ventilation amount and the temperature for multiple times and converging them every time at every prescribed time interval, the ventilation amount and the temperature are calculated.

Description

  The present invention relates to a prediction system for predicting a ventilation situation inside a building and a temperature situation due to heat transfer by calculation.

  Conventionally, ventilation network calculation is used to predict the ventilation situation inside a building. Fig. 10 shows a conceptual diagram of conventional ventilation network calculation. FIG. 10 (a) is a layout diagram of a building, and FIG. 10 (b) shows a network model with each room as one point.

  In the figure, the network consists of only a room and a ventilation path, and the ventilation volume is calculated for each room from the pressure difference between the rooms and the resistance of the ventilation path, assuming the temperature of the outside air, the wind speed, and the temperature of each part of the room. The pressure difference between the chambers is caused by the outside air flow, the chamber-to-chamber or the temperature difference between the inside and outside. Here, the ventilation network calculation is generally performed with the outside air temperature and the typical indoor temperature constant in order to easily handle the effect of the temperature difference between the inside and outside.

  Similarly, a heat load calculation program for calculating a temperature condition inside a building has been used conventionally. In this calculation, the indoor airflow is considered as a heat transfer element, but it is only set as an initial condition, and it is impossible to grasp the ventilation situation.

  However, in buildings, the air temperature rises due to heat generated by heaters, appliances, and sunshine, and airflow is generated due to the temperature difference between the rooms. There is no such thing that considers thermal effects such as temperature distribution and heat generation inside the building.

  In addition, when a more detailed calculation is to be performed, the indoor ventilation and temperature conditions inherently affect each other. However, the calculation of ventilation volume and temperature has not been predicted at the same time in the past, and when predicting the ventilation situation, the temperature situation is given as a condition, and conversely, when predicting the temperature situation, the ventilation situation is given as a condition. It was.

  In particular, when calculating the status of 24-hour planned ventilation with a relatively small ventilation amount, the temperature unevenness due to heat generation inside the building as described above is a level that cannot be ignored as the power of ventilation. In the case of scavenging by ventilation such as opening a window, the amount of ventilation is large and there are few cases where internal heat generation becomes a problem.

  Therefore, the present invention predicts the ventilation and temperature conditions in the building with high accuracy by taking into account the effects of heat transfer and heat generation in the calculation of the ventilation network, and also accurately predicts the indoor air quality. The purpose is to provide a system.

In order to solve the above-mentioned problems, a typical configuration of a building temperature and ventilation prediction system according to the present invention predicts the temperature of each room of a building and the ventilation amount between rooms or inside and outside the building at an arbitrary time. An input means for inputting house-specific data including the shape of each room and connection between rooms such as walls, floors, openings, etc., and weather data including wind speed and outside air temperature, and at predetermined time intervals a calculation means for calculating the temperature and ventilation of each chambers, and output means for outputting a calculation result, the calculation means, taking into account the buoyancy due to a difference in air density due to temperature, air in each chamber The ventilation volume of each opening is calculated by calculating the ventilation volume of each room and maintaining the sum of the inflow and outflow of air in each room to be 0. Calculate temperature for each room based on heat input / output , Per consideration buoyancy due to a difference in air density due to the temperature at the ventilation calculation, the temperature will be referred to with the temperature obtained from the calculation of the temperature of the respective chambers, at predetermined time intervals, Ventilation volume and temperature are calculated each time by calculating and converging the ventilation volume and temperature alternately several times.

In addition, another typical configuration of the building temperature and ventilation prediction system according to the present invention is a system that predicts the temperature of each room of the building and the ventilation amount between rooms or inside and outside the building at an arbitrary time,
Input means for inputting house-specific data including the shape and opening of each room, and weather data including wind speed and outside air temperature;
A calculation means for calculating the temperature and ventilation of each chambers at predetermined time intervals, and output means for outputting a calculation result, the calculation means, taking into account the buoyancy due to a difference in air density due to temperature , determine the amount of ventilation air in each chamber, and the outflow of the incoming sum of the aerial to calculate the ventilation of the respective openings by maintaining the 0 in each chamber, considering heat transfer due to the air by ventilation The temperature for each room is calculated based on the amount of heat input / output between the rooms, and the buoyancy due to the difference in air density due to the temperature is taken into account in the ventilation volume calculation. Suppose that the temperature obtained from the calculation of the temperature is used, and that the ventilation volume is calculated first using the temperature calculated in the previous time every predetermined time interval, and the temperature is calculated using the calculation result of the ventilation volume. Features.

  As described above, the ventilation amount and temperature prediction system for a building according to the present invention predicts the ventilation and temperature conditions in the building with high accuracy by taking into account the effects of heat transfer and heat generation in the ventilation network calculation. In addition, the indoor air quality can be accurately predicted.

It is a conceptual diagram of the prediction system concerning this application. It is a flowchart of the heat and ventilation network calculation concerning 1st embodiment. It is a figure explaining the variable definition around a thick part thermally. It is a figure explaining the model of a dirt floor. It is a flowchart of the heat and ventilation network calculation concerning 2nd embodiment. It is a figure which shows the example of calculation of the temperature distribution in the standard state in a building. It is a figure which shows the example of calculation of the ventilation frequency distribution in the standard state in a building. It is a figure which shows the example of calculation of the ventilation frequency distribution when a clearance area expands. It is a figure which shows the example of calculation of the temperature distribution when a clearance area expands. It is a conceptual diagram of the conventional ventilation network calculation.

[First embodiment]
A first embodiment of a building ventilation and temperature prediction system according to the present invention will be described with reference to the drawings. The building ventilation amount and temperature prediction system according to the present embodiment is specifically software that operates on a computer, the input means means a keyboard, an input / output device, a network line, etc., and the calculation means means a CPU and RAM means output means means a monitor, a printer or a recording device.

(overall structure)
Fig. 1 is a diagram showing the concept of heat and ventilation network calculation. Fig. 1 (a) is a layout diagram of the building. Fig. 1 (b) shows a network model with each room as one point. It shows. In the ventilation path, openings such as doors and gaps between the rooms and between the rooms, and a passage for forced ventilation by a ventilation fan are considered. In the heat transfer path, the amount of heat transferred from the walls, floor and ceiling, etc. and the amount of heat transferred by ventilation are considered. Further, as shown in the figure, indoor air quality is also predicted by taking into consideration the quantitative heat generation source or heat absorption source and the generation source of humidity and chemical substances in each room.

  FIG. 2 shows a flowchart of heat and ventilation network calculation. Specific individual calculations will be described later. As shown in FIG. 2, the house-specific data and weather data of the target building are read from the input means (S1, S2), and the following calculation is performed using them. As shown in Fig. 1 (a), the data for each residence is the layout of the building, the shape of each room, the connection between rooms such as walls, floors, openings, etc., the heat capacity of the members or parts that make up the building, and the indoor arrangement It includes any heat source that is Commercial data can be used as meteorological data, and information on wind speed and outside air temperature, outside air humidity, solar radiation, or radiation amount is used. Even if there is no wind speed data, it is possible to calculate as no wind condition.

  After reading the house data and the meteorological data, the meteorological conditions at the time to be calculated are first acquired (S3), and the amount of radiation given to the building from solar radiation is calculated (S4). Next, the ventilation network calculation is performed to calculate the ventilation amount for each room, and the ventilation amount between the rooms is calculated (S5). Next, the temperature (S6) for each room by the thermal network calculation is calculated using the ventilation volume calculated in S5. And using the temperature calculated by S6, it returns to ventilation network calculation (S5), and also calculates a ventilation quantity. These ventilation network calculation (S5) and thermal network calculation (S6) are repeated until convergence. Then, the humidity and chemical substance concentration (S7) are calculated by calculating the circuit network such as humidity, and after calculating the heat load from the obtained temperature (S8), the calculation result is output (S9).

  These series of calculations (S3 to S8) are repeatedly performed at predetermined time intervals, and output (S9) is performed each time. The predetermined time interval can be set as appropriate, for example, every 30 minutes or every hour. Here, since the ventilation network calculation (S5) and the temperature calculation (S6) have a strong influence on each other, they are repeatedly calculated a plurality of times until they are stabilized.

  By resolving and converging the temperature and ventilation conditions each time in this way, it is possible to obtain a balanced result by correlating ventilation volume and temperature, and to make meaningful predictions with high accuracy. it can.

  Since there is no previous calculation result to be used at the first iteration, the room temperature is calculated by giving an appropriate initial value. Accordingly, the calculation can be made closer to the actual value by starting the calculation from a certain time before the desired time (for example, one and a half months before) and repeating the calculation.

  In addition, the humidity information in the room and the generation rate of chemical substances are affected by the temperature, humidity, and concentration of chemical substances in the surroundings, so temperature information is important in addition to ventilation conditions. Therefore, it is possible to predict the air quality with high accuracy by performing prediction calculation by combining the generation rate of chemical substances by ventilation (movement speed and diffusion speed) with such generation speed.

  In addition, when calculating the thermal network in a building, it is necessary to consider the heat insulation performance of each part of the building and calculate the air conditioning load, such as calculating the heat flow from the internal / external temperature difference and the indoor temperature difference. . Therefore, the heating / cooling load can be obtained by integrating the amount of input heat by the heat source.

  Next, each part calculation is demonstrated.

(Calculation of radiation)
The radiation amount means radiation including solar radiation, and in this embodiment, direct solar radiation amount, sky solar radiation amount and night radiation amount are used. When the commercial weather data to be used contains only the horizontal solar radiation amount, it is divided into the direct solar radiation amount and the sky solar radiation amount by calculation based on the solar altitude. The solar altitude is calculated from the latitude, longitude and date / time of the target city. The amount of radiation is taken into account for outdoor radiation and indoor radiation.

  The meanings of symbols used for outdoor radiation are listed in the following table.

Normal surface direct solar radiation I _b [W / m ² ], horizontal sky solar radiation I _d [W / m ² ], nighttime radiation I _x [W / m ² ], and sine of solar altitude from weather data (sin h), cosine (cos h), solar sine (sin A), and cosine (cos A) can be obtained. Unit vector n _s that indicates the direction of the sun can be defined as follows.

The _radiation vector J _Hjik [W / m ² ] received by the kth thermally thick part H _{ijk of} the connection surface ij is denoted by n _eij as the outward normal vector of the connection surface ij connecting the room i and the outdoor j. Is expressed as follows.

  The same can be calculated for a door that is a thermally thin part. All windows are considered to be reflected or transmitted, and the amount of radiation absorbed by the glass is always considered to be zero.

  The following table shows the meanings of the symbols used for indoor radiation.

  Indoor radiation (1) Accumulate the amount of radiation entering the room (intrusion of solar radiation from windows), (2) Add the amount of radiation generated in the room, such as an electric lamp, and (3) Calculate the accumulated amount of radiation in the room. It is calculated by apportioning the walls, floors, ceilings, etc.

(1) The amount of radiation entering the room is basically the same as in the case of the outer wall. The amount of solar radiation I _Gijk [W] that enters the room i through the k-th window G _{ijk of the} connection surface ij that connects the room i and the room j is expressed by the following equation.

The radiation shielding coefficient SCR and the convection shielding coefficient SCC are given in advance as physical property values. η ^* is the solar radiation penetration rate of the standard plate glass and is a function of the solar radiation angle. The area of the window AGijk [m ² ] is the area of the window that is exposed to the sun (the part that is not shaded), and the area can be calculated geometrically from the shapes of the window and the eyelid.

(2) The radiation amount I _i0 [W] generated in the room is given as a boundary condition, and the value is added as it is. From the above, the total amount of radiation I _i [W] in the room is given by the following equation.

  (3) For the summation and apportionment of indoor radiation, for example, when apportioning the total amount of radiation Ii present in the room as described above, 50% of the radiation is on the floor and the remaining 50% is on the other surface. , Distributed in proportion to the area. The distributed radiation is actually partly reflected, but it is assumed that it will eventually be absorbed by any wall, and all will be absorbed regardless of the absorption coefficient. However, the radiation that hits the window goes outside as it is. That is, it can be expressed by the following formula.

However, A _Fi [m ² ] is the area of the floor constituting the room i, and A _i [m ² ] is the total surface area constituting the room i including A _Fi .

(Ventilation network calculation)
In the ventilation network calculation, the meaning of the symbols used is listed in the following table.

  In the present embodiment, the amount of air entering and exiting the room is (1) a set value that matches the mechanical ventilation by the ventilation facility, and (2) a value calculated in consideration of the draft. (1) Forced ventilation refers to mechanical ventilation such as a ventilation fan, or ventilation between rooms or inside and outside the building by the user, and explicitly specifies the flow rate. Further, (2) the draft air flows through the opening using the outdoor wind speed and the indoor / outdoor / room temperature difference as the motive power, and this item is affected by the temperature of each room. In the ventilation network, it is considered that the ventilation volume instantaneously reaches equilibrium due to the incompressibility of air, and pseudo steady calculation is performed.

The ventilation flow rate V _ijk [m ³ / s] flowing through the k-th opening (gap) M _ijk existing in the chamber i and the chamber j and the pressure difference Δp _ijk [Pa] have the following relationship.

n is usually 1 to 2, but n = 2 in the case of a simple opening, and n = 2 in this embodiment. On the other hand, the air density ρ _A and the opening area A _Mijk [m ³ ] are handled as a large opening in the case of an open door, and the corresponding gap area is substituted for a small gap.

On the other hand, the pressure difference Δp _ijk is calculated from the following equation.

Here, p ^* _ijk and p ^* _jik are pressures [Pa] in consideration of the buoyancy on the i side and j side of the opening, and h _i and h _ijk are the heights [m] of the chamber i and the opening M _ijk . Δρ _i is the density difference [kg / m ³ ] from the standard temperature (θ ₀ = 20 ° C.), and is expressed by the following equation.

k _ρ = 0.00411 kg / m ³ ° C, and the temperature θ _i [° C] of the chamber i is obtained from a thermal circuit network described later. Substituting this expression into equation (7), the following equation.

The pressure p _i is unknown when the chamber i is literally an indoor “chamber”, but is given as a boundary condition from the outside air temperature and the wind speed when it is an external space. The external pressure due to wind is expressed as a dynamic pressure expressed by the following equation.

Believed that this is equivalent to p _i of Equation 9, the pressure of the wall becomes the following equation.

Here, h _i is the height of the center of the outdoors, and all pressures move relatively in equilibrium no matter where they are defined, so h _i = 0.

On the other hand, α ^* is a wind pressure coefficient (which is a variable and is input according to the shape) and is a function of the positional relationship between the wall and the wind direction. As an example, according to the literature, it is +0.8 on the windward side and -0.4 on the leeward side. When smoothly connected, the unit wind direction vector is v / | v | and the unit normal vector of the wall is ne. Can do.

  Moreover, the mass conservation formula for each chamber, that is, the following formula, can be created for the number of chambers.

The number 6 described above is created one for each opening, the number 13 is created for the number of chambers, and the unknowns are the flow rate V _{ijk for} each opening for the number of openings and the pressure p _i for the number of chambers. Therefore, since the number of equations coincides with the number of unknowns, this simultaneous equation can be solved in principle. In Table 3, each term is defined from the viewpoint of the flow rate flowing from the room j to the room i. However, as shown in FIG. In that case, in a room that is in contact with the outdoors, the relationship between the outdoors and the room is also processed by the above processing.

As is apparent from Equation 6, the ventilation network is a quadratic simultaneous equation and is not linear like the thermal network or the humidity network. Therefore, this network performs convergence calculation by iterative solution. Any method can be used as long as a solution can be finally obtained. In this embodiment, the concept of the Marquardt method is applied based on the Newton method.

(Thermal network calculation)
The meanings of the symbols used in the thermal network calculation are listed in the following table.

  In the present embodiment, the amount of heat transmitted to the chamber i is (1) the amount of heat transmitted from a thermally thick portion, (2) the amount of heat transmitted from a thermally thin portion, and (3) transmitted from the ground through the dirt floor. It is calculated taking into account the amount of heat, (4) the amount of heat transferred by ventilation, and (5) the amount of heat generated from the heat source. (1) A thermally thick portion refers to a wall or floor / ceiling, and is calculated in consideration of the heat capacity, and can serve as a thermal buffer to follow changes over time in heat transfer. (2) A thermally thin part means a door, glass, etc., and performs calculation without considering heat capacity. (3) Soil floor is heat transmitted from the floor in contact with the ground. (4) The amount of heat transferred by ventilation is calculated using the air flow rate calculated by the ventilation network. (5) The heat source means a heating / cooling device or a person, and explicitly specifies the amount of heat.

(1) In the calculation of the thermally thick region, with the effective heat capacity of the thermally thick region, the center of the thermal resistivity of the site as a thermal boundary, divides the site. The heat capacities C _Hijk [J / m2 ° C.] and C _Hjik [J / m 2 ° C.] on the i side and the j side of the kth thick portion H _ijk connecting the chambers i and j are defined as follows.

Here, p is a value within the width d of the part H _ijk ,

Is such a value. The surface temperatures T _Hijk and T _Hjik are used as representative temperatures for both sides of the divided parts (see FIG. 3).

  The heat balance equation of i side and j side of Hijk is as follows.

Here, J _Hijk or the like is the amount of heat obtained on the i-side surface of the site Hijk by radiation, and the value obtained by the calculation of the amount of radiation is used. This formula is used as a backward difference

  When discretized using, the following equation is obtained.

Since the number 18 can be made by the number of thermally thick portions, the amount of heat qHijk flowing into the chamber i is expressed by the following equation.

(2) When calculating the thermally thin part, the balance of the left half and right half of the wall for the kth thermally thin part (door, glass, etc.) L _ijk of the joint surface ij connecting the chambers i and j. Since the heat capacity of the thermally thin portion can be regarded as zero, the equation becomes as follows.

Accordingly, the amount of heat q _Lij flowing into the chamber i is expressed by the following equation.

  (3) The amount of heat transmitted from the ground through the dirt floor is also calculated by the thermal network as in the case of the wall. In the case of the wall, the double-layer air layer is used, whereas the dirt floor is in contact with the ground. Is different. The clay floor is modeled with the image shown in FIG. Considering a model in which only the inner half of the wall is taken out and attached directly to the ground, the calculation is divided into the outer peripheral part and the central part.

Since there is only the inner half, there is nothing equivalent to the boundary boundary thermal resistance γ _Hjik , C _Hjik , or T _Hjik on the outdoor side in the case of walls. In terms of the calculation method, the calculation is the same as that of the wall, _assuming that γ _Hjik = C _Hjik = 0 and T _Hjik = θ _j . θ _j is represented by the ground temperature (θ _G ) in the case of a soil floor, and γ _Hijk , C _Hijk , T _Hijk are replaced with γ _Gik , C _Gik , T _Gik, etc., respectively.

Therefore, the heat balance equation of the dirt floor _Gik is as follows.

Therefore, the amount of heat q _Gik flowing into chamber i is

Of the variables used in the above two equations, γ _Gik and A _Gik are input as conditions, and J _Gik is calculated in the same manner as (1) above. Since γ _Gik includes the thermal resistance of the interior material in addition to the film resistance of the floor, the definition point of T _Gik is on the back side of the interior material. As a result, the radiation to the floor is applied to the back side of the interior material unlike the actual situation.

(4) The amount of heat transferred by ventilation is given by the following equation, where V _ijk [m ³ / s] is the flow rate passing through the opening M _ijk from the chamber j to i.

The flow rate V _ijk between the rooms is calculated by the ventilation network or given as a boundary condition.

  (5) The heat source is a quantitative heat source generated by a heating / cooling device or a person, and the heat generation amount Q is input as a condition.

  The heat balance equation in the chamber i using the equation of the heat flow rate determined above is as follows.

By substituting the number 19,21,23,24 to the number 25, it is the equation for T and theta. Further theta = By using several _{18,20 {θ 1, θ 2,} ... θ N} the can simultaneous linear equations such as: whose variable.

Here, A is an N × N matrix, and b and θ are vectors of length N. Solving this, the room temperature θ _i at time step n can be obtained. In this embodiment, the direct method (Gaussian elimination method) is used as this solution.

(Humidity network calculation)
The following table shows the meanings of the symbols used in calculating the network such as humidity.

  A circuit network such as humidity is used to calculate humidity and chemical substance concentration, but is essentially the same as a thermal circuit network. However, since there is no movement through the wall, it is much easier. The conservation formula of the chamber i with respect to the water vapor concentration is as follows.

In Equation 27, if Ci / R = 1, ρA = 1, and Li / R = 0, the chemical substance conservation formula is obtained.

Here, V _ijk is a ventilation amount [m ³ / s] from the k-th opening from room j to i. The above formula can be created for the number N of rooms, and the room humidity or latent heat load can be calculated by solving simultaneous linear equations of N elements.

(Heat load calculation)
When determining the thermal load, gives a temperature to be maintained at room temperature θ in the number 26 of the heat network calculation is determined as the residual of the equation (H = Aθ-b) [ W]. That is, by setting the set temperature, the room temperature, and the heat capacity, the load amount = the room heat capacity [J / m ³ ] * (set temperature−room temperature) is obtained. In the case of cooling, it is -1.

  [Second Embodiment] Next, a second embodiment of a building ventilation and temperature prediction system according to the present invention will be described with reference to FIG. FIG. 5 is a flowchart of heat and ventilation network calculation according to the present embodiment, and the same parts as those in the first embodiment are denoted by the same reference numerals and the description thereof is omitted.

  In the first embodiment described above, in each calculation at every predetermined time interval, the ventilation network calculation (S5) and the thermal network calculation (S6) are described to be repeated a plurality of times until they converge at each time.

  However, in this embodiment, as shown in FIG. 5, the ventilation network calculation (S5) and the thermal network calculation (S6) are performed only once each time, the result is output, and the process proceeds to the next time calculation.

  By configuring as described above, the calculation result can be obtained in a shorter period, although the accuracy is slightly lower than that shown in the first embodiment. Ventilation network changes drastically at each time interval due to the influence of wind direction and wind speed that changes with time, so calculating temperature using the ventilation volume at the previous time is likely to cause a large error. The change in temperature is relatively gentle with respect to time, and even if the ventilation volume is calculated using the temperature at the previous time, it is considered that there will be no significant error. There was little difference between the two embodiments.

  [Calculation Example] FIG. 6 shows an example of calculating the temperature distribution in the building in the layout as shown in the figure. The outdoor conditions are the cold weather in the Tokyo region. Turn on the air conditioner until 22:00 on the previous day and set the temperature of each room to 20 ° C. Yes. Note that doors and windows are closed, and forced ventilation such as a ventilation fan is considered (hereinafter, this is the standard state).

  As shown in FIG. 6, it is shown (or predicted) by simulation that the second floor is colder than the first floor. In addition to heat transfer due to simple heat transfer, warm air rises due to buoyancy, so the influence of the first floor tends to be negative and the second is positive compared to outside air is taken into account. . In addition, rooms that are mechanically exhausted, such as toilets, have negative pressure, so there is an inflow of air from the adjacent corridor to compensate for this, and due to this effect, the corridor also becomes negative pressure and the living room The simulation shows that airflow has entered from a relatively hot room such as that the room temperature is higher than in other rooms.

  The effect of heat transfer due to such airflow and its chain can only be calculated by calculating the ventilation network as well as the heat network by heat transfer for the calculation of heat. Especially for the calculation of the influence of buoyancy, the calculation of the thermal network is necessary. In other words, it is a simulation result that is possible only by solving both networks alternately.

  FIG. 7 shows the distribution of the ventilation frequency in the building in the above layout. Here, the ventilation frequency is a value obtained by dividing the amount of air circulated during a predetermined time by the volume of the room or the like, and indicates the number of times the room air has been replaced. FIG. 7 shows the distribution of the degree of internal ventilation corresponding to the naturally occurring wind direction and air volume when the door is closed (standard state).

  FIG. 8 shows a case where a window that is in contact with the second-level staircase is slightly opened with respect to the above-described standard state. As shown in the figure, it is assumed that the clearance area of the building has expanded compared to when it is closed, and opening the window in contact with the second floor staircase increases ventilation in the area adjacent to the hall. I understand that.

  FIG. 9 is an example in which the temperature distribution in the building is calculated when a few windows in contact with the second floor staircase are opened. As described above, since the ventilation characteristics when the gap is changed are different, it is understood that the temperature distribution in the building also changes due to the influence as a result of calculation taking this into consideration. That is, as shown in FIG. 9, it can be seen that the second floor stair hall, the corridor adjacent to the second floor stair hall, and the first floor stair portion connected to the second floor stair hall increase the ventilation amount and the temperature decreases.

C ... heat capacity
H ... thick part
J ... The amount of heat obtained on the surface
R: Effective heat capacity
T ... surface temperature
d… Width γ… Boundary layer thermal resistance θ… Temperature

Claims (2)

A system for predicting the temperature of each room of a building and the ventilation between rooms or inside and outside the building at any time,
Input means for inputting house-by-house data including the connection between the rooms, such as the shape of each room and walls, floors, openings, etc., and weather data including wind speed and outside air temperature,
Calculation means for calculating the temperature and ventilation volume for each room at predetermined time intervals;
Output means for outputting the calculation result,
Said calculating means,
Taking into account the buoyancy due to the difference in air density due to temperature, calculate the air ventilation volume in each room, and maintain the sum of air inflow and outflow in each room to calculate the ventilation volume for each opening. And
Considering the heat transfer with air due to ventilation, calculate the temperature of each room by the amount of heat input and output between each room,
In considering the buoyancy due to the difference in air density due to the temperature in the calculation of the ventilation volume, the temperature is a temperature obtained from the calculation of the temperature for each room,
A ventilation volume and temperature prediction system for a building which calculates ventilation volume and temperature by calculating and converging the ventilation volume and temperature alternately a plurality of times every predetermined time interval. A system for predicting the temperature of each room of a building and the ventilation between rooms or inside and outside the building at any time,
Input means for inputting house-specific data including the shape and opening of each room, and weather data including wind speed and outside air temperature;
Calculation means for calculating the temperature and ventilation volume for each room at predetermined time intervals;
Output means for outputting the calculation result,
Said calculating means,
Taking into consideration the buoyancy due to the difference in density of air with temperature, determine the amount of ventilation air in each chamber, and calculating the ventilation of the respective openings by maintaining the sum of the inflow and outflow of air in each chamber to 0 And
Considering the heat transfer with air due to ventilation, calculate the temperature of each room by the amount of heat input and output between each room,
In considering the buoyancy due to the difference in air density due to the temperature in the calculation of the ventilation volume, the temperature is a temperature obtained from the calculation of the temperature for each room,
A building ventilation volume and temperature prediction system characterized in that, at a predetermined time interval, the ventilation volume is calculated first using the temperature calculated in the previous time, and the temperature is calculated using the calculation result of the ventilation volume.

Images