JP5233448B2 - Calculation method of smoke layer bottom height, evaluation method of evacuation safety performance in case of fire of building, program for executing this calculation method or evaluation method, and calculation system of smoke layer bottom height - Google Patents

Description

  The present invention relates to a method for calculating the lower end height of a smoke layer as an evaluation index of evacuation safety performance at the time of a building fire, and an evaluation method of evacuation safety performance at the time of a building fire. Moreover, it is related with the program which performs this calculation method or evaluation method, and the calculation system of the lower end height of a smoke layer.

Evacuation safety performance evaluation when a fire occurs in a building room, etc. is whether or not smoke generated by the fire falls to a height that hinders evacuation in the time until the occupant evacuates to a safe place It is common to evaluate with. For smoke property prediction of a fire space, a computer model such as BRI2002 (for example, refer to Non-Patent Document 1), a calculation formula defined in the evacuation safety verification method (for example, refer to Non-Patent Document 2), the effect of smoke emission It is common to use any one of simple calculation formulas (for example, see Non-Patent Document 3) that ignores.
"BRI2002: Two-layer zone smoke flow model and prediction calculation program", Japan Association for Architectural Research, 2003, P1-4 “Ministry of Construction 12 Year Declaration No. 1441”, P302-315 Tanaka Yasuyoshi, “Introduction to Revised Architectural Fire Safety Engineering”, Nippon Architectural Center, 2002, p22-23

  When using a computer model such as BRI2002, it is difficult to grasp the relationship between design elements (floor area, ceiling height, smoke emission amount, smoke outlet installation position, etc.) and smoke fall time, and specialists in fire safety engineering Otherwise, there is a problem that it cannot be used. Moreover, the calculation formula prescribed | regulated by the evacuation safety verification method can be used even if it is not a fire expert, but there exists a problem that calculation accuracy is bad. The simple calculation formula has the same accuracy as BRI2002 and can be used without being a fire specialist, but there is a problem that the effect of the smoke exhausting equipment cannot be expected.

  On the other hand, the present inventor is calculated somewhat safer than a computer model such as BRI2002, but the design elements (floor area, ceiling height, smoke emission amount, smoke outlet installation position, etc.) and smoke layer bottom height Japanese Patent Application No. 2008-173005 proposes a simple prediction formula (hereinafter referred to as “previous prediction formula”) in which the relationship between the two can be easily grasped. And this prediction formula has better calculation accuracy than the evacuation safety verification method. Moreover, it can be used even if it is not a fire specialist, and it is also possible to expect the effect of smoke removal equipment.

Here, the previous prediction formula was proposed assuming a fire source (heat generation rate Q _f ) that increases in proportion to the square of time t as indicated by the dotted line in FIG. 1, that is, the following formula: It is.

However, when the sprinkler facility is activated during a fire, the expansion of the fire is suppressed from the middle, or the expansion of the fire is suppressed from the middle due to a small amount of flammable material in the living room, the following formula or FIG. in as shown by the solid line, the fire as heat release rate Q _f at time t _c which sprinkler system has expanded combustion throughout actuated time t _c or combustible material surface becomes a constant value Q _{c (fire} expansion stops) It is more practical to assume, and the accuracy of predicting the lower end height of the smoke layer is also expected to increase.

  The present invention has been made in view of such a conventional problem, and can easily calculate the lower end height of a smoke layer caused by a fire in a living room of a building equipped with smoke exhausting equipment, and the living room. The calculation method of the smoke layer lower end height, the evaluation method of the evacuation safety performance at the time of fire of the building, the calculation method or the evaluation method that can take into account the phenomenon that the expansion of the fire is suppressed by the operation of the sprinkler equipment in the building An object is to provide a program to be executed and a calculation system for the lower end height of the smoke layer.

In order to achieve this object, the invention shown in claim 1
When a fire occurs in a room of a building where smoke exhausting equipment is installed, a method for calculating a lower end height Z [m] of a smoke layer formed by the smoke of the fire,
The heating rate Q _f [kW] of the fire source in the living room is the fire growth rate α [kW / s ² ] of the fire, the transition time t _c [s], the heating rate Q _c [kW] after the transition, and Using the elapsed time t [s] from the occurrence of the fire,
Given by equation 1-1 above,
The smoke start time t _sm [s], which is the time required from the occurrence of a fire to the start of smoke exhaust, is equal to or longer than the transition time t _c [s], and the elapsed time t [s] is the smoke start time t _sm [s] ] In the above cases,
The lower end height H _c [m] of the smoke layer at the transition time t _c [s] is set as the smoke generation coefficient C _m [kg / kJ ^1/3 / m ^5/3 / s ^{2 / 3} ], the fire growth rate α [kW / s ² ], the transition time t _c [s], the density ρ _s [kg / m ³ ] of the smoke layer, the floor area A _f [m ² ] of the living room, And the ceiling height H _f [m] of the living room,
Calculated by the above equation 1-2,
The lower end height Z [m] of the smoke layer at the elapsed time t [s] is the heat generation rate Q _c [kW] after the transition, the density ρ _s [kg / m ³ ] of the smoke layer, and the floor area A _f [m ² ], the smoke generation coefficient C _m [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ], the smoke emission coefficient C _sm related to the emission of smoke from the room by the smoke removal facility [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ], transition time t _c [s], smoke emission start time t _sm [s], smoke layer lower end height at transition time t _c Using the length H _c [m] and the elapsed time t [s],
It is calculated by the above equation 1-3.

According to the invention shown in the first aspect, the phenomenon that the expansion of the fire is prevented from the middle of the elapsed time t by the operation or the like of the sprinkler, the calculation formula of the heat release rate Q _f before and after the transition time t _c The simulation is performed by dividing into two cases (see the above equation 1-1). Then, the above formula 1-3 for calculating the lower end height Z of the smoke layer in the above claim 1 is defined by incorporating these two formulas, and the lower end height required for the calculation of the formula 1-3 is defined. the above equation 1-2 for calculating the H _c is defined. Therefore, if it calculates based on said Formula 1-3, calculation of the lower end height Z of the smoke layer which considered the suppression phenomenon of the said fire expansion can be performed with high precision.

Further, since the above expression 1-3 has input parameters related to smoke emission such as the smoke emission coefficient C _sm and the smoke emission start time t _sm, the smoke layer is also considered in consideration of the smoke emission effect by the smoke emission equipment. Can be calculated with high prediction accuracy.

Furthermore, it corresponds to the input parameters A _f , H _f , α, Q _c , ρ _s , C _m , C _sm , t, t _c , and t _{sm in} the above formulas 1-3 and 1-2. As long as a specific numerical value is substituted, the lower end height Z of the smoke layer can be easily calculated.

The invention according to claim 2 is a method for calculating the lower end height Z [m] of the smoke layer formed by the smoke of the fire when a fire occurs in the room of the building where the smoke exhausting facility is installed. Because
The heating rate Q _f [kW] of the fire source in the living room is the fire growth rate α [kW / s ² ] of the fire, the transition time t _c [s], the heating rate Q _c [kW] after the transition, and Using the elapsed time t [s] from the occurrence of the fire,
Given by equation 2-1 above,
The transition time t _c [s] is equal to or longer than the smoke start time t _sm [s], which is the time required from the occurrence of a fire to the start of smoke exhaust, and the elapsed time t [s] is the transition time t _c [s]. In the above case,
The smoke layer lower end height H _c [m] at the transition time t _c [s], the fire growth rate α [kW / s ² ], the smoke layer density ρ _s [kg / m ³ ], the living room Floor area A _f [m ² ], smoke generation coefficient C _m [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ] related to the generation of smoke due to fire, the transition time t _c [s], Smoke emission coefficient C _sm [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ], smoke emission start time t _sm [s], and Using the ceiling height H _f [m] of the living room,
Calculated by the above equation 2-2,
The lower end height Z [m] of the smoke layer at the elapsed time t [s] is the heat generation rate Q _c [kW] after the transition, the density ρ _s [kg / m ³ ] of the smoke layer, and the floor area A _f [m ² ], smoke generation coefficient C _m [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ], smoke emission coefficient C _sm [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ], the transition time t _c [s], and the lower end height H _c [m] of the smoke layer at the transition time t _c [s], and the elapsed time t [s],
It is calculated by the above equation 2-3.

According to the second aspect of the present invention, the phenomenon in which the expansion of the fire is suppressed from the middle of the elapsed time t due to the operation of the sprinkler facility, etc., is calculated using the formula for calculating the heating rate Q _f before and after the transition time t _c. This is simulated by dividing into two cases (see the above equation 2-1). Then, incorporate these two equations, along with the equation 2-3 to calculate the lower height Z of the smoke layer is specified to calculate the lower height H _c required for the calculation of the formula 2-3 The above equation 2-2 is defined. Therefore, if it calculates based on said Formula 2-3, calculation of the lower end height Z of the smoke layer which considered the suppression phenomenon of the said fire expansion can be performed with high precision.

Moreover, since the said Formula 2-2 and the said Formula 2-3 have the input parameters which concern on smoke emission, such as smoke emission coefficient _Csm and smoke release start time _tsm , the smoke emission effect by smoke emission equipment The lower end height Z of the smoke layer can be calculated with high prediction accuracy.
Furthermore, it corresponds to the input parameters A _f , H _f , α, Q _c , ρ _s , C _m , C _sm , t, t _c , and t _{sm in} the above formulas 2-3 and 2-2. As long as a specific numerical value is substituted, the lower end height Z of the smoke layer can be easily calculated.

Invention of Claim 3 is the calculation method of the lower end height of the smoke layer of Claim 1 or 2,
The transition time t _c [s] is
The time t _sp [s] required from the occurrence of the fire to the operation of the sprinkler equipment in the living room, or the time t _fuel required from the occurrence of the fire until the combustion spreads over the entire surface of the combustible material associated with the fire source. [s] or a time t _op [s] required from the occurrence of the fire until the fire becomes a ventilation-controlled fire.

  According to the third aspect of the present invention, the lower end height Z of the smoke layer can be calculated on the safe side. In general, when the sprinkler equipment is installed or the amount of combustible material is small, the heat generation rate at the time when the sprinkler equipment is activated or when the combustion spreads over the entire combustible material surface is the maximum value. However, in this respect, the sprinkler equipment is activated by adding the configuration of claim 3 to the configuration related to the heat generation rate of formula 1-1 of claim 1 and formula 2-1 of claim 2. This is because it is a safe calculation if it is assumed that the rate of heat generation is constant (fire expansion stops) at the time of combustion or when the combustion spreads over the entire surface of the combustible material.

Invention of Claim 4 is the calculation method of the lower end height of the smoke layer in any one of Claims 1 thru | or 3, Comprising:
The smoke start time t _sm [s] is
The time t _detect [s] required from the occurrence of the fire until the fire detector in the room detects the fire, or the time t _start [s] required for the occupant in the room to start evacuation from the occurrence of the fire s] or more.

According to the invention described in claim 4, the smoke start time t _sm is the time t _detect required from the occurrence of the fire until the fire detector of the living room detects the fire, or from the occurrence of the fire to the living room. Since it is set to a value equal to or longer than the time t _start required for the occupant in the room to start evacuation, it is possible to perform a calculation in accordance with the actual situation. This is because the smoke outlet is generally opened in conjunction with the fire sensor or artificially opened by a manual opening device.

Invention of Claim 5 is the calculation method of the lower end height of the smoke layer in any one of Claims 1 thru | or 4, Comprising:
The smoke emission coefficient C _sm [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ] is
Flue gas volume m _e per unit time _[kg / s], heat release rate Q _f of fire source _[kW], with the lower end of the smoke layer height Z [m],
It is calculated by the above equation 5-1.

According to the fifth aspect of the present invention, the smoke emission coefficient C _sm [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ] is the smoke generation coefficient C _m [kg / kJ ^1/3 / m ^{5 / 3} / s ^2/3 ], it is expressed as the same dimension, so it is possible to easily grasp the reduction effect due to smoke emission.

Invention of Claim 6 is the calculation method of the lower end height of the smoke layer in any one of Claim 1 thru | or 5, Comprising:
The density ρ _s [kg / m ³ ] of the smoke layer is obtained by using the temperature T _s [K] of the smoke layer at the elapsed time t [s],
It is calculated by the above equation 6-1.

According to the sixth aspect of the present invention, the density ρ _s [kg / m ³ ] of the smoke layer is calculated in consideration of the temperature T _{s of the} smoke layer at the elapsed time t. Changes in ρ _s can also be reflected in the calculation of the lower end height of the smoke layer, enabling more accurate prediction.

The invention shown in claim 7 is a method for evaluating evacuation safety performance at the time of fire of a building based on the calculation method of the lower end height of the smoke layer according to any one of claims 1 to 6,
When the time from the occurrence of the fire until the occupant in the room completes evacuation is defined as t _escape , the time t _escape is substituted for the elapsed time t, so that the lower end of the smoke layer at the time of evacuation completion Calculating the height Z _escape ;
A step of comparing the calculated lower end height Z _escape of the smoke layer with a limit smoke layer height H _{lim for} evacuation safety.
According to the seventh aspect of the present invention, if the height Z _escape of the smoke layer at the time when the evacuation is completed and the limit smoke layer height H _lim are simply compared, the evacuation at the time of fire of the building Safety performance can be evaluated.

The invention described in claim 8 is a program that causes a computer to execute the calculation method according to any one of claims 1 to 6 .
According to the eighth aspect of the present invention, the calculation method can be executed by a data processing device such as a computer. Further, the program can be distributed using an electric communication line such as the Internet, so that the applicant can easily use the calculation method .

The invention according to claim 9 is a calculation for calculating the lower end height Z [m] of the smoke layer formed by the smoke of the fire when a fire occurs in the room of the building where the smoke exhausting facility is installed. A system,
It has a numerical operation processing unit that performs numerical operations,
The heating rate Q _f [kW] of the fire source in the living room is the fire growth rate α [kW / s ² ] of the fire, the transition time t _c [s], the heating rate Q _c [kW] after the transition, and Using the elapsed time t [s] from the occurrence of the fire,
Given by equation 9-1 above,
The smoke start time t _sm [s], which is the time required from the occurrence of a fire to the start of smoke emission, is equal to or longer than the transition time t _c [s], and the elapsed time t [s] from the occurrence of the fire is the smoke start time t _In case of _sm [s] or more,
The numerical operation processing unit
The lower end height H _c [m] of the smoke layer at the transition time t _c [s] is set as the smoke generation coefficient C _m [kg / kJ ^1/3 / m ^5/3 / s ^{2 / 3} ], the fire growth rate α [kW / s ² ], the transition time t _c [s], the density ρ _s [kg / m ³ ] of the smoke layer, the floor area A _f [m ² ] of the living room, And the ceiling height H _f [m] of the living room,
Calculated by the above equation 9-2,
The lower end height Z [m] of the smoke layer at the elapsed time t [s] is the heat generation rate Q _c [kW] after the transition, the density ρ _s [kg / m ³ ] of the smoke layer, and the floor area A _f [m ² ], the smoke generation coefficient C _m [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ], the smoke emission coefficient C _sm related to the emission of smoke from the room by the smoke removal facility [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ], transition time t _c [s], smoke start time t _sm [s], smoke layer at the transition time t _c [s] Using the lower end height H _c [m] and the elapsed time t [s],
It is calculated by the above equation 9-3.
According to the ninth aspect of the invention, the same effect as that of the first aspect can be achieved.

The invention shown in claim 10 is a calculation for calculating the lower end height Z [m] of the smoke layer formed by the smoke of the fire when a fire occurs in the room of the building where the smoke exhausting facility is installed. A system,
It has a numerical operation processing unit that performs numerical operations,
The heating rate Q _f [kW] of the fire source in the living room is the fire growth rate α [kW / s ² ] of the fire, the transition time t _c [s], the heating rate Q _c [kW] after the transition, and Using the elapsed time t [s] from the occurrence of the fire,
Given by equation 10-1 above,
The transition time t _c [s] is equal to or longer than the smoke start time t _sm [s], which is the time required from the occurrence of a fire to the start of smoke exhaust, and the elapsed time t [s] is the transition time t _c [s]. In the above case,
The numerical operation processing unit
The smoke layer lower end height H _c [m] at the transition time t _c [s], the fire growth rate α [kW / s ² ], the smoke layer density ρ _s [kg / m ³ ], the living room Floor area A _f [m ² ], smoke generation coefficient C _m [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ] related to the generation of smoke due to fire, the transition time t _c [s], Smoke emission coefficient C _sm [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ], smoke emission start time t _sm [s], and Using the ceiling height H _f [m] of the living room,
Calculated by the above equation 10-2,
The lower end height Z [m] of the smoke layer at the elapsed time t [s] is the heat generation rate Q _c [kW] after the transition, the density ρ _s [kg / m ³ ] of the smoke layer, and the floor area A _f [m ² ], smoke generation coefficient C _m [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ], smoke emission coefficient C _sm [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ], the transition time t _c [s], and the lower end height H _c [m] of the smoke layer at the transition time t _c [s], and the elapsed time t [s],
It is calculated by the above equation 10-3.
According to the tenth aspect of the present invention, the same effect as that of the second aspect can be achieved.

  According to the calculation method of the lower end height of the smoke layer, the evaluation method of the evacuation safety performance at the time of fire of the building, and the calculation system of the lower end height of the smoke layer according to the present invention, the building having the smoke exhausting equipment It is possible to easily calculate the lower end height of the smoke layer caused by the fire in the living room of the object, and to take into account the phenomenon that the expansion of the fire is suppressed by the operation of the sprinkler equipment in the living room, etc. It becomes possible to calculate the lower end height of the layer with high accuracy.

=== This Embodiment ===
The calculation method of the lower end height of the smoke layer according to the present embodiment is, for example, when evaluating the evacuation safety performance at the time of a building fire in a building design stage, or a plan change or application change stage of an existing building. Used for.

  The calculation method of the lower end height of the smoke layer (hereinafter also referred to as the lower end height of the smoke layer) is as follows. As shown in FIG. 2, the smoke exhaust effect by the smoke exhaust facility such as the exhaust port 10 and the operation of the sprinkler facility, etc. This is a method of calculating the smoke layer lower end height while taking into consideration both the phenomenon in which the expansion of the fire is suppressed from the middle of the fire (hereinafter referred to as the fire expansion suppression phenomenon).

And about the latter fire expansion suppression phenomenon, the assumed fire source concerning a fire is simulated by making it a compound fire source as shown in the following Formula 1 and the graph of FIG. That is, this assumed fire source is a growth fire source (a fire source in which the heat generation rate Q _f [kW] increases in proportion to the square of the time t) at the beginning of the fire, but after the transition time t _c has elapsed, It is assumed that the heat source (heat generation rate Q _f is a constant value Q _c fire source regardless of time) is transferred.

Therefore, when the elapsed time t is defined starting from the occurrence of a fire, the simple prediction formula for the smoke layer lower end height is the transition time t _c for shifting from the growth source to the steady source, and the exhaust from the room. There are two cases depending on the magnitude relationship with the smoke start time t _sm when smoke starts.

FIG. 4A is an explanatory diagram when the smoke emission start time t _sm is equal to or longer than the transition time t _c (t _c ≦ t _sm : Case 1). Conversely, FIG. 4B shows that the transition time t _c is the smoke emission start time. It is explanatory drawing in the case of t _sm or more (t _sm ≦ t _c : Case 2).

Here, in each time range A, B, and C shown in these two figures, the time range in which the fire is affected by both the smoke emission effect and the fire expansion suppression phenomenon is the smoke emission start time in case 1 of FIG. 4A. The time range C after t _sm , that is, the time range C in which the elapsed time t is greater than the smoke start time t _sm (t _sm ≦ t), on the other hand, in case 2 of FIG. 4B, the transition time t _c A time range C later than that, that is, a time range C in which the elapsed time t is larger than the transition time t _c (t _c ≦ t). Therefore, the calculation target time range of the calculation method according to the present embodiment is the time range C (t _sm ≦ t) in the case 1 of FIG. 4A, and the time range C (t in the case 2 of FIG. 4B. _c ≦ t).

And the simple prediction formula of the smoke layer lower end height Z in the time range C (t _sm ≦ t) in case 1 is expressed by the following formula 2.
Here, H _c in the above equation 2 is the lower end height H _c of the smoke layer at the transition time t _c [s], and is represented by the following equation 3.
The meanings of the other parameters are as follows.
A _f : Floor area of the room [m ² ]
H _f : Ceiling height of the room [m]
α: Fire growth rate of the growth source [kW / s ² ]
Q _c : Heat generation rate of stationary fire source [kW]
C _m : Smoke generation coefficient related to smoke generation [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ]
C _sm : Smoke emission coefficient related to smoke emission from the room [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ]
t: Elapsed time since the occurrence of the fire [s]
t _c : Transition time for transition from a growth source to a steady source [s]
t _sm : Smoke start time [s], which is the time required from the start of a fire to the start of smoke
ρ _s : smoke layer density [kg / m ³ ]
Then, as long as the corresponding specific numerical values are substituted for these parameters A _f , H _f , α, Q _c , ρ _s , C _m , C _sm , t, t _c , t _sm , the case 1 The smoke layer lower end height Z can be easily obtained with respect to an arbitrary elapsed time t within the time range C (t _sm ≦ t).

On the other hand, the simple prediction formula in the time range C (t _c ≦ t) of case 2 in FIG. 4B is expressed by the following formula 4.
Here, H _c in the above equation 4 is the lower end height H _c of the smoke layer at the transition time t _c [s], and is represented by the following equation 5.
The meanings of the other parameters are as described above.

Then, if the corresponding specific numerical values are substituted for these parameters A _f , H _f , α, Q _c , ρ _s , C _m , C _sm , t, t _c , t _sm , the case of Case 2 The smoke layer lower end height Z can be easily obtained for an arbitrary elapsed time t within the time range C (t _c ≦ t).

Incidentally, as a reference, simple prediction formulas of time range A (t ≦ t _c ) and time range B (t _c ≦ t ≦ t _sm ) of case 1 shown in FIG. 7

Similarly, as a reference, simple prediction formulas of the time range A (t ≦ t _sm ) and the time range B (t _sm ≦ t ≦ t _c ) of Case 2 shown in FIG. The following formula 9 is obtained.

Then, the corresponding specific numerical values are substituted into the parameters A _f , H _f , α, Q _c , ρ _s , C _m , C _sm , t, t _c , t _sm in the above equations 6 to 9. As long as this is done, the smoke layer lower end height Z in the case 1 and the case 2 can be easily obtained with respect to an arbitrary elapsed time t within the time range A and the time range B.
Hereinafter, each parameter α, Q _c , ρ _s , C _m , C _sm , t _c , and t _sm will be described. A method for deriving Equations 2 and 4 according to this embodiment will be described later.

(1) Growth rate α of growth fire source
As described above, assuming that the fire source at the beginning of the fire is a growth fire source Q _f (heat generation rate) [kW] that increases in proportion to the square of the time t [s] as shown in the following formula 10. Yes.
The proportionality constant α [kW / s ² ] in the above equation 10 is the fire growth rate α. This fire growth rate α is calculated from, for example, the result of an assumed combustible material combustion experiment, or calculated by the following equation 11 based on the Evacuation Safety Verification Act (2000 Decree No. 1441). .
Α _f is a fire growth rate [kW / s ² ] due to combustion of combustible materials stored in the fire space, and is set according to combustible materials such as furniture in the fire space. On the other hand, α _m is the fire growth rate [kW / s ² ] due to combustion of the interior material of the fire space, and is set in consideration of the non-combustibility of the finishing material constituting the wall and ceiling of the fire space. The relationship between the various conditions related to the fire space and the specific values of the fire growth rates α _f and α _m are described in contrast to 2000 Decree No. 1441, and shall be set with reference to this. be able to.

(2) Heat generation rate Q _{c of} steady fire source
The heat generation rate Q _c [kW] of the steady fire source is the heat generation rate Q _sp [kW] when the sprinkler facility is operated, the heat generation rate Q _fuel [kW] when the combustion spreads over the entire combustible surface, or the ventilation-controlled fire Any minimum value of the heat generation rate Q _op [kW] may be used.
The heat generation rate Q _sp [kW] during the operation of the sprinkler equipment can be calculated from the fire source to the sprinkler head according to the literature (Takayoshi Tanaka “Revised Architecture Fire Safety Engineering Introduction”, Nippon Building Center, 2002, p174-175). Using the horizontal distance r [m], the operating temperature T _sp [K] of the sprinkler equipment, and the ceiling height H _f [m] of the fire space.

The heat generation rate Q _fuel when combustion spreads over the entire surface of the combustible material is obtained by multiplying the heat generation rate q ”[kW / m ² ] per unit area of the combustible material and the surface area A _fuel [m ² ] of the combustible material. And can be calculated by the following equation 13.

The heat generation rate q ”[kW / m ² ] per unit area of combustible materials is generally 130 to 400 [kW / m ² ], but the fire resistance verification method (Ministry of Construction 2000 1443) can be set to 48 [kW / m ² ] when calculated as the combustion type control factor χ = ∞, and is the surface area of the combustible material A _fuel calculated according to the actual situation? Alternatively, it is possible to use a calculation method defined in the Fire Resistance Performance Verification Act (Ministry of Construction 2000 Decree No. 1443).

The heat generation rate Q _op [kW] during a ventilation-controlled fire, according to the literature (Tanaka Yoshiyoshi, “Revised Architecture Fire Safety Engineering Introduction”, Nippon Building Center, 2002, p196), is the area of the opening of the fire room. Using A _op [m ² ] and the height H _op [m], it can be calculated by the following equation 14.
When the heat generation rate Q _c [kW] of the steady fire source is expressed by the following equation 15, the transition time t _c [s] can be calculated by the following equation 16.

(3) Transition time t _{c for} transition from a growth source to a steady source
The transition time t _c includes, for example, the time t _sp [s] required from the occurrence of the fire to the operation of the sprinkler equipment in the living room, or the entire surface of the combustible material related to the fire source from the occurrence of the fire. The time t _fuel [s] required for the combustion to expand is set.
And if these time _tsp or _tfuel is set, it will be a safe assumption. When the sprinkler equipment is installed or the amount of combustible material is small, the heat generation rate at the time when the sprinkler equipment is activated or the combustion spreads over the entire surface of the combustible material is the maximum value. Therefore, in the calculation, it is assumed that the rate of heat generation will be constant (when the fire spread stops) when the sprinkler facility is activated or when the combustion spreads over the entire combustible surface. It becomes.

(4) Smoke generation coefficient C _m
The smoke generation coefficient C _m is a coefficient when the surrounding air is entrained and expanded when a hot air stream containing combustion gas or soot generated from a fire rises. As the value, for example, as shown as a constant in “Introduction to Revised Architectural Fire Safety Engineering” of Non-Patent Document 3, 0.08 or 0.076 [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ] is used. However, there is a report that when the sprinkler equipment is activated, it will be 1.6 to 2.2 times the normal time (Reference: Yuta Kuwana et al .: Smoke properties in the compartment when the sprinkler equipment is activated-Fire plume measurement and consideration-, Japanese Architecture Summary of Academic Conference Academic Lecture (A-2), pp.245-246, 2007).

(5) Smoke start time t _sm
The smoke emission start time t _sm is the time [s] required from the occurrence of a fire until the smoke emission facility starts smoke emission. Therefore, the smoke start time t _sm is, for example, a value that is greater than or equal to the time t _detect [s] required from the occurrence of a fire until the fire detector detects the fire, or the evacuation start time t _start [s] or more Is set to the value of

(6) Smoke emission coefficient C _sm
Flue coefficient ^{_{C sm [kg / kJ 1/3 /}} m 5/3 / s 2/3] is flue gas per unit time and m _e [kg / s], fire source heat release rate Q _f [kW] Based on the smoke layer lower end height Z [m], the following equation 17 is calculated.

Here, since the heat source heating rate Q _f [kW] and smoke layer lower end height Z [m] generally change from moment to moment, the smoke emission coefficient C _sm [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ] also changes. However, except for the case where the amount of flue gas is very large compared to the legal amount of air flow, the flue gas coefficient C _sm is considered to gradually increase with the passage of time, so as to start flue gas as parameters m _e , Q _f and Z Smoke amount m _{e (sm)} [kg / s] at the time (smoke start time t _sm ), fire source heat generation rate Q _{f (sm)} [kW] at the start of smoke discharge, smoke at the time of smoke start If the lower layer height Z _(sm) [m] is used and the following equation 18 is used for calculation, the assumption on the safe side is assumed.
Note that a safer assumption can be made by calculating using the ceiling height H _f [m] of the fire space instead of the smoke layer lower end height Z _(sm) [m] at the start of smoke emission.

In addition, the smoke emission amount me _(sm) [kg / s] at the start of the smoke emission in the above equation 18 is, for example, the smoke emission air amount E stipulated in the Evacuation Safety Verification Act of 2000 Decree No. 1441. Using [m ³ / min], it can be calculated by the following equation 19. Here, ρ _s is the density of the smoke layer [kg / m ³ ], but if it is set to 1.0 [kg / m ³ ] considering that the start of smoke emission is the initial stage of fire Absent.

Further, the heat source heat generation rate Q _{f (sm)} [kW] at the start of smoke emission in the above equation 18 is calculated by the following equation 20.

Further, the smoke layer lower end height Z _(sm) [m] at the start of smoke emission in the above equation 18 is the case where the smoke emission start time t _sm [s] is equal to or longer than the transition time t _c [s], that is, the case described above. In the case of 1, it is calculated by the following equation 21,
On the other hand, when the smoke emission start time t _sm [s] is equal to or shorter than the transition time t _c [s], that is, in the case 2 described above, the calculation is performed by the following expression 22.
Here, A _f is the floor area [m ² ] of the fire space, H _f is the ceiling height [m] of the fire space, and C _m is the smoke generation coefficient [kg / kJ ^1/3 / m ^5/3 / s ^{2 / 3} ] (= 0.08 or 0.076 [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ]), α is the fire growth rate [kW / s ² ], ρ _s is the smoke layer density [kg / m ³ ]. Flue gas at the start by considering that the initial stage of fire, [rho no problem by setting the 1.0 kg / m ³ in the _s.
The above equation 21 is obtained by substituting the smoke start time t _sm which is the time at the start of smoke emission into the elapsed time t of the above equation 7, and the above equation 22 is the passage of the above equation 8. The smoke emission start time t _sm , which is the time at the start of smoke emission, is substituted for the time t (see FIGS. 4A and 4B).

(7) Smoke density ρ _s
If the density ρ _{s of the} smoke layer is set to 1.0 [kg / m ³ ], for example, a calculation result on the safe side can be obtained. Therefore, it may be calculated as 1.0 [kg / m ³ ]. However, since the smoke layer density ρ _s may become less than 1.0 after the smoke evacuation facility is activated, preferably, the smoke layer temperature T _s [K] is used to calculate the following equation 23. More accurate prediction is possible.
Note that the meaning of the operation symbol “min (,)” in Expression 23 is that the calculated value of 353 / T _s is compared with 1.0, and the smaller value is used as the smoke layer density ρ _s. is there. The former “353 / T _s ” is based on the physical principle of ρ _s × T _s = 353 (constant).

Here, an example of how to obtain the smoke layer temperature T _s [K] in Equation 23 will be described.
The amount of heat Q _f generated from the fire source at a certain time is used to warm the air amount m _p [kg / s] (initial temperature T _∞ ) entrained by the rising airflow over the fire source to the smoke layer temperature T _s Assuming that heat is distributed to the amount of heat and the amount of heat lost by heat transfer to the peripheral wall, that is, assuming that the energy conservation equation of the following equation 24 holds, the smoke layer temperature T _s [K] is transformed as the following equation 25: Is done.
Here, fire source heat generation rate in the Q _f is the elapsed time t [kW], c _p is the specific heat at constant pressure [kJ / kgK], smoke generation amount at the time of m _p is the elapsed time t [kg / s], A w is The ceiling and peripheral wall area [m ² ] of the part where the smoke layer contacts, h _k is the effective heat transfer coefficient [kW / m ² K] at the elapsed time t, and T _∞ is the ambient air temperature [K].

The smoke generation amount m _p [kg / s] in the above equation 25 is calculated by the following equation 26 assuming the smoke generation amount at the smoke layer lower end height (limit smoke layer height H _lim ) that hinders evacuation safety. This is a safe calculation. Further, the limit smoke layer height H _lim in the following formula 26 is generally set to 1.8 [m]. Here, as described above, C _m is the smoke generation coefficient (= 0.08 or 0.076) [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ], and Q _f is the time at the elapsed time t. It is the heat source heat generation rate [kW], and is calculated by the above-mentioned equation 1.

In addition, the heat transfer coefficient h _k [kW / m ² K] in the above equation 25 Can be calculated as an effective value according to the following equation 27 according to “Introduction to the revised version of architectural fire safety engineering” of Non-Patent Document 3. Here, lambda _c is a ceiling (wall) material thermal conductivity of [kW / mK], ρ _c is the density of the ceiling (wall) material ^{[kg / m 3], c} c is the specific heat of the ceiling (wall) material [kJ / kgK], t is the elapsed time [s]. In addition, since Equation 27 may take a very large value at the initial stage of the fire, it is preferable to set an arbitrary value of 0.015 to 0.023 [kW / m ² K] as the upper limit value.

By the way, the smoke layer density ρ _{s at the} transition time t _{c and} the smoke layer density ρ _{sm at} the smoke start time t _sm used for the calculation of the smoke exhaust coefficient C _sm are calculated using the formulas 23 to 27. It is also possible to calculate _s .
For example, when the smoke layer lower end height Hc of the transition time t _c [s] is obtained using the above-described formula 3 and formula 5, the smoke layer density ρ _s in the formula 3 and formula 5 is determined. Thus, the value obtained by the above equation 23 may be substituted. In this case, the transition time t _c is substituted for the elapsed time t of the parameter necessary for the calculation of Equation 23 described above. For example, with respect to the smoke layer temperature T _s according to Equation 23, the temperature T _s of the smoke layer in the transition time t _c is substituted or the like.
On the other hand, in the calculation of flue coefficient C _sm described above, when calculating the density [rho _s smoke layer of flue start time t _sm, to the elapsed time t parameters required for the calculation of Equation 23 above The smoke emission start time t _sm is substituted.

As mentioned above, although the calculation method of the smoke layer lower end height which concerns on this embodiment has been demonstrated, the effect of this calculation method is demonstrated here.
First, in this calculation method, the phenomenon that the expansion of the fire is suppressed from the middle of the elapsed time t due to the operation of the sprinkler facility, etc. is expressed in two formulas for calculating the heat generation rate Q _f before and after the transition time t _c. The simulation is performed by dividing the case (see Equation 1). Then, by incorporating this formula 1, the formula 2 is defined as a simple prediction formula of the smoke layer lower end height Z in the case 1 (t _c ≦ t _sm ), and the case 2 (t _sm The above formula 4 is defined as the simple prediction formula in the case of ≦ t _c ). Therefore, if it calculates based on Formula 2 and Formula 4, the calculation of the lower end height Z of the smoke layer which considered the suppression phenomenon of the said fire expansion can be performed with high precision.

Further, the expression 2 and the expression 4 or the expression 5 necessary for the calculation of the expression 4 has input parameters related to the flue gas such as the flue gas coefficient C _sm and the flue gas start time t _sm. The smoke layer lower end height can be calculated with high prediction accuracy in consideration of the smoke emission effect of the equipment.

Furthermore, this calculation method is applicable to the input parameters A _f , H _f , α, ρ _s , C _m , C _sm , t, t _c , and t _{sm in} the equations 2 and 4. As long as a specific numerical value is substituted, the smoke layer lower end height Z can be immediately calculated. Therefore, it is possible to easily obtain the smoke layer lower end height Z even if not an expert.

FIG. 5 is a graph for verifying the prediction accuracy improvement effect that can be achieved by Equation 2 of Case 1 (t _c ≦ t _sm ). The vertical axis represents the smoke layer lower end height Z [m], which is the calculation result, and the horizontal axis represents the elapsed time t [s] from the occurrence of the fire. For comparison, the graph also plots the calculation result by the above-mentioned evacuation safety verification method and the calculation result by the computer model for comparison. Here, the calculation results using the computer model can be found in the literature (Mamiko Kumeme, Tomoyoshi Tanaka: A method for evaluating evacuation safety based on the required amount of flue gas, The Architectural Institute of Japan Environmental Studies Vol.586, p1-8, 2004 In other words, it is a so-called so-called exact solution (the most accurate calculation result) calculated strictly in consideration of the smoke emission effect by the smoke emission facility.

In addition, as for the precondition of calculation in all graphs, the smoke generation coefficient C _m = 0.076 [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ], fire growth rate α = 0.0125 [kW / s ² ] , Floor area A _f = 3000 [m ² ], ceiling height H _f = 2.8 [m], mechanical smoke exhaust system (smoke flow rate W = 1000 [m ³ / min]) Regarding Equation 2, the transition time t _c is further set to 173 [seconds], the heat generation rate Q _c after the transition time t _{c has} elapsed is set to 3000 [kw], and the smoke emission start time t _sm is set to 329 [seconds]. ] Is set.

Further, as described above, since the time range to be calculated in Expression 2 is the time range C where t _sm ≦ t, the other time ranges A (t ≦ t _c ) and time ranges B (t _c ≦ t ≦ t) t _sm ) is calculated by the above-described Equation 6 and Equation 7, respectively.

Referring to FIG. 5, in the evacuation safety verification method, the calculation result of the computer model that is rigorously solved is greatly deviated over the entire range of the elapsed time t. According to, the calculation result close to the exact solution of the computer model is obtained, and it can be seen that the prediction accuracy is dramatically improved. Further, although it is predicted to be excessively safe in the evacuation safety verification method, according to the formula 2 according to the present embodiment, when the time range of the calculation target t _sm 329 seconds or later is seen, the lower end of the smoke layer The height Z is a level that is predicted to be slightly safer than the computer model. Therefore, it can be considered that if Eq. 2 is used, the evacuation safety performance of the building can be evaluated with peace of mind without excessively restricting the design conditions of the building.

  By the way, the calculation method of smoke layer lower end height Z by the above-mentioned formula 2 or formula 4 can be easily executed using a general data processor (equivalent to a calculation system) represented by a personal computer. Examples of the data processing device include a central processing unit (CPU: equivalent to a numerical operation processing unit), a data recording device such as a hard disk device, an output device such as a monitor, an input device such as a keyboard, and a CD-ROM drive device. A normal personal computer equipped with a data reader can be used.

The data recording apparatus stores in advance an arithmetic program for calculating the above-described Equation 2 or Equation 4, and the CPU reads and executes the arithmetic program. That is, specific numerical values input by the input device are input parameters A _f , H _f , α, ρ _s , C _m , C _sm , t, t _c , and t _sm in Expression 2 or 4. by substituting the calculation of Hc according to formula 3, or a smoke layer lower height Z calculated through the calculation of the H _c according to equation 5, to monitor displays the serving calculations smoke layer lower height Z.

  Here, general-purpose spreadsheet software such as “Microsoft Excel” (trademark) of US Microsoft Corporation can be used as the arithmetic program. For example, when the “Microsoft Excel” is started, a worksheet including a large number of cells arranged vertically and horizontally is displayed on the monitor, and the designer can change the formula 2 or the formula 4 to a predetermined cell (reference source Cell). At this time, the input parameters constituting the expression 2 are associated with a reference destination cell for inputting a specific numerical value of the input parameter so that the input parameter can be calculated in the predetermined cell (reference source cell). . Therefore, if a specific numerical value is input to the reference destination cell, the formula 2 or the formula 4 is automatically calculated based on the specific numerical value, and the smoke layer lower end height Z as a calculation result is set to each reference source cell. And is displayed on the monitor.

  Such a calculation program may be recorded in advance in a data recording device, or a calculation program recorded in a data recording medium such as a CD-ROM may be read by the data reading device. good. Furthermore, the personal computer may be connected to a telecommunication line such as the Internet and downloaded from a server computer connected to this line.

=== Evaluation Method for Evacuation Safety Performance of Buildings in Fire Using the Calculation Method of this Embodiment ===
FIG. 6 is a flowchart of a method for evaluating the evacuation safety performance at the time of fire using the above-described Formula 2 or Formula 4. In addition, this evaluation is suitably performed in the design stage of a building, the plan change of an existing building, or a use change stage.

In this evaluation method, until the occupant completes evacuation from the room where the fire occurred, the smoke generated by the fire is at a height that hinders evacuation safety (limit smoke layer height H _lim [m]). Safety is judged by whether or not it descends. Here, the smoke layer lower end height Z generally decreases gradually as time t elapses. Therefore, as shown in FIG. 7, safety is evaluated by comparing only the magnitude relationship between the smoke layer lower end height Z _escape and the limit smoke layer height H _{lim at} the time of evacuation completion (evacuation completion time t _escape [s]). it can. In addition, 1.8 [m] is normally used for the limit smoke layer height _Hlim . A method for calculating the evacuation completion time t _escape [s] will be described later.

Hereinafter, a specific procedure of this evacuation safety performance evaluation method will be described with reference to FIG.
First, in step S101, calculation conditions are acquired from a design drawing or the like of a building. That is, the floor area A _f of the living room (fire space), the ceiling height H _f , the fire growth rate α, the smoke generation coefficient C _m , the smoke emission conditions (the smoke emission method, the smoke outlet size, etc.) are acquired. As for the smoke generation coefficient C _m , 0.08 or 0.076 [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ] is registered in Equation 2 or Equation 4 in advance as a predetermined constant. Also good.

Next, in step S102, the transition time t _c is calculated. As described above, the transition time t _c is the time t _sp [s] required from the occurrence of the fire to the operation of the sprinkler equipment in the living room, or the combustibility related to the fire source from the occurrence of the fire. The time t _fuel [s] required for the combustion to spread over the entire object surface, or the time t _op [s] required for the fire to become a ventilation-controlled fire after the occurrence of the fire is set.

Next, in step S103, the smoke start time t _sm is calculated. As described above, the smoke start time t _sm is based on the time t _detect [s] when the fire detector detects a fire, the evacuation start time t _start [s] of the occupant, and the like. Or a value larger than these values is set.

Next, in step S104, the evacuation completion time t _escape is calculated. This evacuation completion time t _escape is the time [s] required for the occupant to complete evacuation after the occurrence of a fire. For example, the method specified in the Evacuation Safety Verification Act of 2000 Decree No. 1441 is used. The sum of the evacuation start time t _start [s], the walking time t _travel [s], and the door passage time t _queue [s] is calculated. Note that the order of these steps S101 to S104 may be changed.

Next, in step S105, the magnitude relationship between the transition time t _c and the smoke emission start time t _sm is compared. In case 1 where t _c ≦ t _{sm, the process} proceeds to step S106, and in case 2 where t _sm ≦ t _{c, the process} proceeds to step S107.

In step S106, the smoke layer lower end height Z _escape at the time of evacuation completion is calculated for case 1 (t _c ≦ t _sm ). This calculation is obtained in the above-described steps S101 to S103 and the like for each of the parameters α, A _f , H _f , C _m , t _c , t _sm , C _sm , and ρ _s of the above formulas 2 and 3. And the smoke _exhaustion coefficient C _sm and smoke layer density ρ _s calculated on the basis of the above parameters and the like, and the evacuation completion time t _escape obtained in step S104 to the elapsed time t of the equation 2 This is done by substituting. Note that the calculation of the smoke emission coefficient C _sm and the smoke layer density ρ _s may be calculated in advance before step S106.

On the other hand, when the process proceeds to step S107, the smoke layer lower end height Z _escape at the time of completion of evacuation is calculated for case 2 (t _sm ≦ t _c ). This calculation is obtained in the above-described steps S101 to S103 and the like for each of the parameters α, A _f , H _f , C _m , t _c , t _sm , C _sm , and ρ _s of the above-described equations 4 and 5. And the smoke emission coefficient C _sm and smoke layer density ρ _s calculated on the basis of the above parameters and the like, and the evacuation completion time t _escape obtained in step S104 to the elapsed time t of the equation 4 This is done by substituting. As in step S106 described above, the smoke emission coefficient C _sm and the smoke layer density ρ _s may be calculated in advance prior to step S107.

Then, in the last step S108, the smoke layer lower end height Z _escape calculated in step S106 or step S107 is compared with the predetermined limit smoke layer height H _lim . When the Z _escape is equal to or higher than the limit smoke layer height H _lim , it is determined that the building is safe and the evaluation of the evacuation safety performance is finished. On the other hand, the Z _escape is the limit smoke layer height If it is less than H _lim, it is determined that the building is dangerous, the design of the building is changed in step S109, and then the process returns to step S101. Under the new calculation condition based on the changed drawing, the above-described operation is performed. Steps S102 to S108 are repeated.

=== Regarding Derivation Methods of Equation 2 and Equation 4 According to the Calculation Method of the Present Embodiment ===
<<< basic equation >>>
Here, the derivation method of the above-mentioned Formula 2 and Formula 4 is demonstrated. First, as shown in FIG. 2, in a room having a fixed ceiling height and having no hindrance to the flow of smoke such as a hanging wall (regardless of the planar shape), the room is divided into a smoke layer and an air layer. Considering the state, the smoke layer mass conservation formula when the smoke exhaust system is operating is: smoke layer volume is V [m ³ ], smoke is generated m _p [kg / s], and effective smoke is m _{e When} expressed as [kg / s], it can be expressed as the following formula 31.
Here, the density ρ _s [kg / m ³ ] of the smoke layer changes depending on the temperature of the smoke layer, but in the following, Equation 31 is developed _assuming that ρ _s is constant.

The smoke layer volume V can be expressed by the following equation 32 using the fire room floor area A _f [m ³ ], the ceiling height H _f [m], and the smoke layer lower end height Z [m].
Therefore, Expression 31 can be transformed as Expression 33 below.

Here, as described in Non-Patent Document 3 “Introduction to Revised Architectural Fire Safety Engineering”, when the smoke generation amount m _p [kg / s] penetrating into the smoke layer is given by the following equation 34: By substituting the following equation 34 into the above equation 33, the following equation 35 is obtained.
C _m [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ] is the smoke generation coefficient described above.

Although the above equation 35 cannot be solved analytically, the equation 35 can be expressed as the following equation 36 when the smoke generation coefficient _Cm is apparently reduced after the operation of the smoke exhausting facility.
Here, C _sm [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ] is defined by the following equation 37, and the amount of smoke that is apparently reduced due to the effect of smoke emission. It is a coefficient.
Therefore, the following equation 38 is obtained by modifying the above equation 36.

<<< Assumed fire source >>>
As the assumed fire source, as described above, a complex fire source that grows in proportion to the square of time and has a constant heat generation rate at a certain time t _c is handled. Therefore, the heat generation rate Q _f of the assumed fire source is given by the following equation 39.
For this reason, different simple prediction formulas for the smoke layer lower end heights are given according to the magnitude relationship between the set transition time t _c [s] and the flue gas start time t _sm [s]. Therefore, hereinafter, the process of deriving the simple prediction formula will be described for each of the above-described case 1 (t _c ≦ t _sm ) and case 2 (t _sm ≦ t _c ).

Furthermore, the flue gas coefficient C _sm is Haikemuriryou m _e, varies with time with the variation of the heat generation rate Q _f and Kemuriso lower height Z, where flue gas coefficient C _sm is flue gas facilities Assuming that it is given to the safe side using the smoke emission amount m _e , the heat generation rate Q _f , and the smoke layer lower end height Z at the smoke emission start time (smoke emission start time t _sm ) at the start of Discuss.

<<< Case 1 (t _c ≦ t _sm ) >>
Case 1 is a case where smoke emission is started after the fire source shifts to a steady state. When the smoke layer lower end height is predicted using this prediction method, the case may be caused by the magnitude relationship of the elapsed time t, the fire source transition time t _c , and the smoke emission start time t _sm , which is the time for which the smoke layer lower end height is to be obtained. It is necessary to divide. Then, the relationship between the transition time t _c and the smoke emission start time t _sm is shown in a graph as shown in FIG. 4A. That is, a simple prediction formula is given for each of a time range A corresponding to t ≦ t _{c, a} time range B corresponding to t _c ≦ t ≦ t _sm, and a time range C corresponding to t _sm ≦ t.

(A) In the time range A (t ≦ t _c) simple prediction expression time in the range A (t ≦ t _c), heat release rate of the fire source can be represented by a first equation of the above equation 39. Since C _sm = 0 before the start of the smoke exhausting equipment, the following equation 40 is obtained by substituting the first equation of the above equation 39 into the aforementioned equation 38 and integrating.
Since (t ₀ , Z ₀ ) = (0, H _f ) at the time of fire occurrence, the above equation 40 can be written as the following equation 41.
Therefore, when the above equation 41 is transformed, the smoke layer lower end height Z at the elapsed time t can be written as the following equation 42.
That is, a simple prediction formula of the smoke layer lower end height Z at an arbitrary elapsed time t within the time range A (t ≦ t _c ) is given by the above formula 42.

(B) in a time range _{B (t c ≦ t ≦ t} sm) simple prediction expression time in the range _{B (t c ≦ t ≦ t} sm) is heat release rate of the fire source is represented by a second equation of the above equation 39 be able to. Since C _sm = 0 before the start of smoke emission before the start of the smoke emission facility, the following equation 43 is obtained by substituting the second equation of equation 39 into the aforementioned equation 38 and integrating.
Here, when placing the smoke layer lower height in the transition time _{t c} of the fire source and _{H c,} the transition time _{t c (t 0, Z 0} ) = (t c, H c) because it is, the above equation 43 Can be written as:
Therefore, when the above equation 44 is transformed, the smoke layer lower end height Z at the elapsed time t can be written as the following equation 45.
Further, the smoke layer lower end height H _c at the fire source transition time t _c can be written by the above equation 42 as the following equation 46.
Therefore, the above equation 45 can be written as the following equation 47 by substituting the above equation 46.
That is, a simple prediction formula of the smoke layer lower end height Z at an arbitrary elapsed time t within the time range B (t _c ≦ t ≦ t _sm ) is given by the above formula 47.

In the simple prediction equation Time range C (t _sm ≦ t) is in (c) a time range C (t _sm ≦ t), heat release rate of the fire source can be represented by a second equation of the above equation 39. Further, since C _sm ≠ 0 after the start of the smoke exhausting facility, the following equation 48 is obtained by substituting the second equation of equation 39 into the aforementioned equation 38 and integrating.
Further, since (t ₀ , Z ₀ ) = (t _sm , Z _sm ) in the above equation 48, the following equation 49 is obtained.
Further, the smoke layer lower end height Z _sm at the smoke start time t _sm can be written by the above equation 45 as the following equation 50.
Here, by substituting the above equation 50 into the above equation 49 and modifying it, the smoke layer lower end height Z at the elapsed time t can be written as the following equation 51, and Hc in the following equation 51 is represented by the above equation 46: Is obtained.
Therefore, a simple prediction formula of the smoke layer lower end height Z at an arbitrary elapsed time t within the time range C (t _sm ≦ t) is given by the above formula 51. And the said Formula 51 is Formula 2 mentioned above, ie, Formula 2 is derived | led-out with the above derivation process.

<<< Case 2 (t _sm ≦ t _c ) >>
Case 2 is a case where the fire source shifts to a steady state after activation of the smoke emission facility, that is, after the start of smoke emission. Similarly, in case 2, it is necessary to classify the cases according to the magnitude relationship among the elapsed time t, the transition time t _c , and the smoke discharge start time t _{sm which is} the time for which the smoke layer lower end height is desired to be obtained. Then, the relationship between the transition time t _c and the smoke emission start time t _sm is shown in a graph as shown in FIG. 4B. That is, simple prediction formulas are given for a time range A where t ≦ t _{sm, a} time range B where t _sm ≦ t ≦ t _c, and a time range C where t _c ≦ t.

In the simple prediction expression time range A (t ≦ t _sm) is in (a) the time range A (t ≦ t _sm), since the growth of fire source and the Muhai smoke condition, the smoke layer lower height, Z, described above It can be represented by Equation 42. That is, the simple prediction formula of the smoke layer lower end height Z at an arbitrary elapsed time t within the time range A (t ≦ t _sm ) is the same as the above formula 42.

(B) in the simple prediction expression time range _{B (t sm ≦ t ≦ t} c) in the time range _{B (t sm ≦ t ≦ t} c) is heat release rate of the fire source is represented by a first equation of the above equation 39 be able to. Since C _sm = 0 before the start of smoke emission before the start of the smoke emission facility, the following equation 52 is obtained by substituting the first equation of equation 39 into equation 38 described above and integrating.
Since (t ₀ , Z ₀ ) = (0, H _f ) at the time of the fire occurrence, the above equation 52 can be written as the following equation 53.
Further, the smoke layer lower end height Z _sm at the smoke start time t = t _{sm which} is the start time of the smoke exhaust system can be written by the above equation 53 as the following equation 54.

Further, in the time range B (t _sm ≦ t ≦ t _c ), the heat generation rate of the fire source can be expressed by the first equation of the aforementioned equation 39. Further, since C _sm ≠ 0 after the start of the smoke exhausting facility, the following equation 55 is obtained by substituting the first equation of equation 39 into the aforementioned equation 38 and integrating.
Further, since (t ₀ , Z ₀ ) = (t _sm , Z _sm ) in the above equation 55, the following equation 56 is obtained.
Here, by transforming the above equation 56, the smoke layer lower end height Z at the elapsed time t is given by the following equation 57, and by substituting the above equation 54 into Z _{sm of the} following equation 57, Equation 58 is obtained.
Therefore, the simple prediction formula of the smoke layer lower end height Z at an arbitrary elapsed time t within the time range B (t _sm ≦ t ≦ t _c ) is given by the above equation 58.

In the simple prediction equation Time range C (t _c ≦ t) is in (c) a time range C (t _c ≦ t), heat release rate of the fire source is represented by a second equation of the above equation 39, and flue gas Since C _sm ≠ 0 after the start-up of the equipment, the conditions are the same as in the above-described equation 48. Therefore, when the smoke layer lower end height at the fire source transition time t _c is set as H _c , (t ₀ , Z ₀ ) = (t _c , H _c ), and therefore, the following expression 59 is obtained.
If the above equation 59 is modified, the smoke layer lower end height Z at the elapsed time t can be written as the following equation 60.
Further, the smoke layer lower end height H _c at the fire source transition time t _c can be obtained by the following equation 61 obtained by substituting the t _c for the elapsed time t of the above equation 58.
Therefore, a simple prediction formula of the smoke layer lower end height Z at an arbitrary elapsed time t within the time range C (t _c ≦ t) is given by the above equation 60. And the said Formula 60 is Formula 4 mentioned above, ie, Formula 4 is derived | led-out with the above derivation process.

=== Other Embodiments ===
As mentioned above, although embodiment of this invention was described, this invention is not limited to this embodiment, The deformation | transformation as shown below is possible in the range which does not deviate from the summary.
In the above-described embodiment, the subject performing the evaluation method of the evacuation safety performance at the time of fire of the building is not particularly mentioned, but the data processing apparatus having the same configuration as described in the calculation method of the present embodiment is shown in FIG. The flow may be executed. Here, the data recording device of the data processing device stores in advance an arithmetic program for executing the flow of FIG. 6, and the central processing unit (CPU) reads and executes the arithmetic program. Needless to say.

It is a diagram showing a relationship between the heat release rate Q _f and time t of the fire source. It is a fire model figure in the room of the building provided with the smoke exhaust (smoke exhaust facility) 10 on the ceiling. It is explanatory drawing of the composite fire source which is an assumption fire source used by this embodiment. 4A is an explanatory diagram of case 1 (t _c ≦ t _sm ), and FIG. 4B is an explanatory diagram of case 2 (t _sm ≦ t _c ). It is a graph for verifying the prediction accuracy improvement effect which Formula 2 concerning the calculation method of this embodiment can show. It is a flowchart of the method of evaluating the evacuation safety performance at the time of a fire using Formula 2 or Formula 4 which concerns on the calculation method of this embodiment. It is explanatory drawing of smoke layer lower end height Z _escape at the time of evacuation completion, and limit smoke layer height _Hlim .

Explanation of symbols

    10 Smoke exhaust (smoke exhaust facility)

Claims (11)

When a fire occurs in a room of a building where smoke exhausting equipment is installed, a method for calculating a lower end height Z [m] of a smoke layer formed by the smoke of the fire,
The heating rate Q _f [kW] of the fire source in the living room is the fire growth rate α [kW / s ² ] of the fire, the transition time t _c [s], the heating rate Q _c [kW] after the transition, and Using the elapsed time t [s] from the occurrence of the fire,

Given by equation 1-1 above,
The smoke start time t _sm [s], which is the time required from the occurrence of a fire to the start of smoke exhaust, is equal to or longer than the transition time t _c [s], and the elapsed time t [s] is the smoke start time t _sm [s] ] In the above cases,
The lower end height H _c [m] of the smoke layer at the transition time t _c [s] is set as the smoke generation coefficient C _m [kg / kJ ^1/3 / m ^5/3 / s ^{2 / 3} ], the fire growth rate α [kW / s ² ], the transition time t _c [s], the density ρ _s [kg / m ³ ] of the smoke layer, the floor area A _f [m ² ] of the living room, And the ceiling height H _f [m] of the living room,

Calculated by the above equation 1-2,
The lower end height Z [m] of the smoke layer at the elapsed time t [s] is the heat generation rate Q _c [kW] after the transition, the density ρ _s [kg / m ³ ] of the smoke layer, and the floor area A _f [m ² ], the smoke generation coefficient C _m [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ], the smoke emission coefficient C _sm related to the emission of smoke from the room by the smoke removal facility [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ], transition time t _c [s], smoke emission start time t _sm [s], smoke layer lower end height at transition time t _c Using the length H _c [m] and the elapsed time t [s],

The calculation method of the lower end height of a smoke layer characterized by calculating by the above Formula 1-3. When a fire occurs in a room of a building where smoke exhausting equipment is installed, a method for calculating a lower end height Z [m] of a smoke layer formed by the smoke of the fire,
The heating rate Q _f [kW] of the fire source in the living room is the fire growth rate α [kW / s ² ] of the fire, the transition time t _c [s], the heating rate Q _c [kW] after the transition, and Using the elapsed time t [s] from the occurrence of the fire,

Given by equation 2-1 above,
The transition time t _c [s] is equal to or longer than the smoke start time t _sm [s], which is the time required from the occurrence of a fire to the start of smoke exhaust, and the elapsed time t [s] is the transition time t _c [s]. In the above case,
The smoke layer lower end height H _c [m] at the transition time t _c [s], the fire growth rate α [kW / s ² ], the smoke layer density ρ _s [kg / m ³ ], the living room Floor area A _f [m ² ], smoke generation coefficient C _m [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ] related to the generation of smoke due to fire, the transition time t _c [s], Smoke emission coefficient C _sm [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ], smoke emission start time t _sm [s], and Using the ceiling height H _f [m] of the living room,

Calculated by the above equation 2-2,
The lower end height Z [m] of the smoke layer at the elapsed time t [s] is the heat generation rate Q _c [kW] after the transition, the density ρ _s [kg / m ³ ] of the smoke layer, and the floor area A _f [m ² ], smoke generation coefficient C _m [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ], smoke emission coefficient C _sm [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ], the transition time t _c [s], and the lower end height H _c [m] of the smoke layer at the transition time t _c [s], and the elapsed time t [s],

The calculation method of the lower end height of a smoke layer characterized by calculating by the above Formula 2-3. It is a calculation method of the lower end height of the smoke layer according to claim 1 or 2,
The transition time t _c [s] is
The time t _sp [s] required from the occurrence of the fire to the operation of the sprinkler equipment in the living room, or the time t _fuel required from the occurrence of the fire until the combustion spreads over the entire surface of the combustible material associated with the fire source. [s], or the time t _op [s] required for the fire to become a ventilation-controlled fire after the occurrence of the fire. It is a calculation method of the lower end height of the smoke layer according to any one of claims 1 to 3,
The smoke start time t _sm [s] is
The time t _detect [s] required from the occurrence of the fire until the fire detector in the room detects the fire, or the time t _start [s] required for the occupant in the room to start evacuation from the occurrence of the fire s] A method for calculating the lower end height of the smoke layer, characterized by having a value equal to or greater than. A method for calculating the lower end height of a smoke layer according to any one of claims 1 to 4,
The smoke emission coefficient C _sm [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ] is
Flue gas volume m _e per unit time _[kg / s], heat release rate Q _f of fire source _[kW], with the lower end of the smoke layer height Z [m],

The calculation method of the lower end height of a smoke layer characterized by calculating by said Formula 5-1. A method for calculating the lower end height of a smoke layer according to any one of claims 1 to 5,
The density ρ _s [kg / m ³ ] of the smoke layer is obtained by using the temperature T _s [K] of the smoke layer at the elapsed time t [s],

The calculation method of the lower end height of a smoke layer characterized by calculating by the above Formula 6-1. A method for evaluating evacuation safety performance at the time of fire of a building based on the calculation method of the lower end height of the smoke layer according to any one of claims 1 to 6,
When the time from the occurrence of the fire until the occupant in the room completes evacuation is defined as t _escape , the time t _escape is substituted for the elapsed time t, so that the lower end of the smoke layer at the time of evacuation completion Calculating the height Z _escape ;
A step of comparing the calculated lower end height Z _escape of the smoke layer with a limit smoke layer height H _{lim for} evacuation safety, comprising the steps of: Evaluation method. A program for causing a computer to execute the calculation method according to any one of claims 1 to 6 . A calculation system for calculating the lower end height Z [m] of a smoke layer formed by smoke of a fire when a fire occurs in a building room where smoke exhausting equipment is installed,
It has a numerical operation processing unit that performs numerical operations,
The heating rate Q _f [kW] of the fire source in the living room is the fire growth rate α [kW / s ² ] of the fire, the transition time t _c [s], the heating rate Q _c [kW] after the transition, and Using the elapsed time t [s] from the occurrence of the fire,

Given by equation 9-1 above,
The smoke start time t _sm [s], which is the time required from the occurrence of a fire to the start of smoke emission, is equal to or longer than the transition time t _c [s], and the elapsed time t [s] from the occurrence of the fire is the smoke start time t _In case of _sm [s] or more,
The numerical operation processing unit
The lower end height H _c [m] of the smoke layer at the transition time t _c [s] is set as the smoke generation coefficient C _m [kg / kJ ^1/3 / m ^5/3 / s ^{2 / 3} ], the fire growth rate α [kW / s ² ], the transition time t _c [s], the density ρ _s [kg / m ³ ] of the smoke layer, the floor area A _f [m ² ] of the living room, And the ceiling height H _f [m] of the living room,

Calculated by the above equation 9-2,
The lower end height Z [m] of the smoke layer at the elapsed time t [s] is the heat generation rate Q _c [kW] after the transition, the density ρ _s [kg / m ³ ] of the smoke layer, and the floor area A _f [m ² ], the smoke generation coefficient C _m [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ], the smoke emission coefficient C _sm related to the emission of smoke from the room by the smoke removal facility [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ], transition time t _c [s], smoke start time t _sm [s], smoke layer at the transition time t _c [s] Using the lower end height H _c [m] and the elapsed time t [s],

The calculation system of the lower end height of a smoke layer characterized by calculating by said Formula 9-3. A calculation system for calculating the lower end height Z [m] of a smoke layer formed by smoke of a fire when a fire occurs in a building room where smoke exhausting equipment is installed,
It has a numerical operation processing unit that performs numerical operations,
The heating rate Q _f [kW] of the fire source in the living room is the fire growth rate α [kW / s ² ] of the fire, the transition time t _c [s], the heating rate Q _c [kW] after the transition, and Using the elapsed time t [s] from the occurrence of the fire,

Given by equation 10-1 above,
The transition time t _c [s] is equal to or longer than the smoke start time t _sm [s], which is the time required from the occurrence of a fire to the start of smoke exhaust, and the elapsed time t [s] is the transition time t _c [s]. In the above case,
The numerical operation processing unit
The smoke layer lower end height H _c [m] at the transition time t _c [s], the fire growth rate α [kW / s ² ], the smoke layer density ρ _s [kg / m ³ ], the living room Floor area A _f [m ² ], smoke generation coefficient C _m [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ] related to the generation of smoke due to fire, the transition time t _c [s], Smoke emission coefficient C _sm [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ], smoke emission start time t _sm [s], and Using the ceiling height H _f [m] of the living room,

Calculated by the above equation 10-2,
The lower end height Z [m] of the smoke layer at the elapsed time t [s] is the heat generation rate Q _c [kW] after the transition, the density ρ _s [kg / m ³ ] of the smoke layer, and the floor area A _f [m ² ], smoke generation coefficient C _m [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ], smoke emission coefficient C _sm [kg / kJ ^1/3 / m ^5/3 / s ^2/3 ], the transition time t _c [s], and the lower end height H _c [m] of the smoke layer at the transition time t _c [s], and the elapsed time t [s],

The calculation system of the lower end height of a smoke layer characterized by calculating by said Formula 10-3. A program for causing a computer to execute the evaluation method according to claim 7.