A centralized smoke exhaust and air supply system for buildings

Abstract

The present invention relates to a centralized building smoke exhaust and air supply system, characterized by comprising indoor range hoods, a public smoke exhaust duct, a public air supply duct, and an air supply system. The indoor range hoods are all DC variable frequency range hoods and operate in a constant air volume control mode. The indoor control box and air supply system are configured such that when the indoor range hood in a resident's kitchen is turned on, the corresponding indoor control box obtains the actual exhaust air volume Q of the indoor range hood and transmits it in real time to the air supply system. The air supply system controls the output air supply volume based on the sum of the actual exhaust air volumes of all turned-on indoor range hoods and simultaneously transmits a control instruction to the indoor control box in the corresponding resident's kitchen, causing it to control the opening angle of the corresponding air supply electric valve so that the air intake volume entering the kitchen is the same as the exhaust volume of the indoor range hood. Compared with the existing technology, the present invention can accurately control the air supply volume entering the user's kitchen, thereby ensuring that the indoor temperature is not affected.

Description

Technical Field

[0001] The invention relates to a centralized smoke exhaust and air supply system for a building. Background Art

[0002] Currently, there are two scenarios for kitchen air supply. One is that in the cold northern regions, doors and windows are closed in winter. When the range hood is running in the kitchen, there will be negative pressure inside the kitchen, resulting in poor exhaust effect of the range hood, so air supply is needed; the other is for a constant temperature indoor environment. When the range hood is running, the air flow in the room and living room is sucked into the range hood, which will quickly disrupt the indoor temperature balance. Therefore, active air supply is also required near the range hood.

[0003] For residential buildings, especially high-rise buildings, the current common solution is split-type air supply, that is, an air supply electric valve is installed on the kitchen ceiling of each residential user. One end of the air supply electric valve is connected to the outside, and the other end is connected to the inside of the kitchen. When the range hood is turned on, the air supply electric valve is opened. When the range hood is turned off, the air supply electric valve is closed to balance the pressure inside the kitchen. Some patents also mention the technical solution of centralized air supply, such as the Chinese utility model patent with publication number CN215001761U, which proposes an air supply system for the kitchen, which includes an air supply power component, an air duct, a pressure detection component and an air supply electric valve component. One end of the air supply power component is connected to the outside world, and the other end is connected to one end of the air supply electric valve component through the air duct. The other end of the air supply electric valve component is connected to the kitchen, and the pressure detection component is connected to the air supply electric valve component. When the above-mentioned air supply system is in use, the air supply electric valve assembly obtains the working status of the range hood. When the range hood is in working state, the pressure detection assembly obtains the pressure difference inside and outside the kitchen. Then the air supply electric valve assembly controls the air supply power assembly and its own working status according to the pressure difference.

[0004] Split-type supply air systems can address the first scenario, but for the second, split-type supply air motorized valves cannot prevent the constant-temperature indoor air from being drawn into the range hood. For example, if the range hood is on and the kitchen door is also open, air will be drawn into the kitchen from the living room or other rooms rather than through the supply air motorized valve. Furthermore, split-type supply air systems require drilling holes in the user's home wall and installing rain shields over the corresponding outdoor air inlets, which can negatively impact the exterior aesthetics and limit the supply air volume. Centralized supply air systems, which operate in conjunction with the range hood, can ensure adequate kitchen air supply. However, accurately controlling the supply air volume is challenging; excessive or insufficient supply air volume can disrupt indoor temperature conditions. Supply air volume is adjusted by adjusting the angle of the electric supply air motorized valve and the power of the outdoor unit. Under normal flue conditions, exhaust resistance is generally higher on lower floors and lower on higher floors, resulting in lower exhaust air volume on lower floors and higher exhaust air volume on higher floors. The supply air volume requirement should be smaller on lower floors and larger on higher floors. This presents a problem: due to the lower supply air volume and proximity to the public supply air duct, the electric supply air valve's opening angle is relatively small. This presents two issues: first, the small angle of the electric supply air valve can create noticeable aerodynamic noise when air flows through it; second, the small angle of the electric supply air valve requires very high angle adjustment precision, as even a 1° difference can significantly affect the supply air volume. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a building centralized smoke exhaust and air supply system that can accurately control the amount of supply air entering the user's kitchen to ensure that the indoor temperature is not affected.

[0006] The technical solution adopted by the present invention to solve the above technical problems is: a centralized smoke exhaust and air supply system for a building, characterized in that it includes: an indoor range hood arranged inside the kitchen of each household in the building, a public smoke exhaust duct arranged inside the building, a public air supply duct arranged inside the building, and an air supply system, wherein the public smoke exhaust duct and the public air supply duct are arranged independently of each other, the air outlet of the air supply system is connected to the inlet of the public air supply duct, and an air supply port is provided inside the kitchen of each household in the building, and the air supply port is directly connected to the public air supply duct or is connected to the public air supply duct through the indoor air supply duct. An electric air supply valve with an adjustable opening angle is provided at the air supply inlet or at the inlet or outlet of the indoor air supply duct; the air outlet of the indoor range hood inside each resident's kitchen in the building is connected to the public exhaust duct through an indoor smoke exhaust pipe; in addition, an indoor control box is also provided inside each resident's kitchen in the building, and the indoor range hoods and electric air supply valves inside different resident's kitchens are all communicatively connected to the indoor control box inside the corresponding resident's kitchen, and the indoor control boxes inside all resident's kitchens are all communicatively connected to the air supply system, and the indoor control boxes inside all resident's kitchens are also communicatively connected to the outdoor auxiliary smoke exhaust system;

[0007] All indoor range hoods are DC variable frequency range hoods, and all indoor range hoods are operated in a constant air volume control mode, that is, all indoor range hoods are pre-set with the functional relationship between the fan speed and exhaust volume under different operating gears: Q = A + B*n + C*n 2 , where A, B, and C are preset constants, and n is the fan speed of the indoor range hood. When the indoor range hood in a household's kitchen is turned on, the actual exhaust volume Q of the indoor range hood is calculated based on the operating gear selected by the user and the current fan operating speed n. Then, the real-time operating gear of the indoor range hood is adjusted based on the actual exhaust volume Q and the target exhaust volume range. If the actual exhaust volume Q is greater than the maximum value of the target exhaust volume range, the operating gear of the indoor range hood is reduced. Conversely, if the actual exhaust volume Q is less than the minimum value of the target exhaust volume range, the operating gear of the indoor range hood is increased. If the actual exhaust volume Q is within the target exhaust volume range, the operating gear of the indoor range hood is maintained unchanged.

[0008] The indoor control box and the air supply system are configured as follows: when the indoor range hood inside a certain household's kitchen is turned on, the indoor control box inside the corresponding household's kitchen obtains the actual exhaust volume Q of the indoor range hood and sends it to the air supply system in real time; the air supply system controls the output air supply volume according to the sum of the actual exhaust volumes of all turned-on indoor range hoods, and at the same time sends a control instruction to the indoor control box inside the corresponding household's kitchen; the indoor control box inside the corresponding household's kitchen controls the opening angle of the corresponding air supply electric valve, so that the air intake volume entering the corresponding household's kitchen is the same as the exhaust volume of the indoor range hood inside the corresponding household's kitchen.

[0009] As an improvement, the air supply ports inside the households on each floor are connected to the public air supply duct through the indoor air supply duct; the public air supply duct is L in length and L in width respectively. x , L y a rectangular parallelepiped pipe; a pressure sensor is provided at the inlet of the common air supply duct, and the pressure sensor is in communication with the air supply system; when the indoor range hood in a certain household's kitchen is turned on, the indoor control box in the corresponding household's kitchen obtains the exhaust volume of the indoor range hood and sends it to the air supply system in real time, and at the same time, the indoor control box in the corresponding household's kitchen controls the air supply electric valve in the household from a closed state to an open state, and adjusts the opening angle of the air supply electric valve in the household to 90°. The air supply system sets an initial pressure value at the inlet of the common air supply duct according to the start-up rate of the indoor range hood, and assigns the initial pressure value to P0, and then executes the following control steps:

[0010] Step 1: Select N sampling points from bottom to top inside the public air supply duct, and record the pressure values at the sections where these N sampling points are located as P1, P2, ... P n-1 , P n , ... P N The first sampling point and the second sampling point are located at the upper and lower sides of the first-floor household air supply inlet or the indoor air supply duct inlet, respectively. The n-1th sampling point and the nth sampling point are located at the upper and lower sides of the n-floor household air supply inlet or the indoor air supply duct inlet, respectively. The N-1th sampling point and the Nth sampling point are located at the upper and lower sides of the N-floor household air supply inlet or the indoor air supply duct inlet, respectively. N is the total number of floors of the building. The pressure value at the cross section of each sampling point in the public air supply duct is then calculated using the following formula:

[0011] P n-1 =P n +△P n1 +△P yn

[0012] In the above formula, P n-1 Indicates the pressure value at the cross section where the n-1th sampling point is located, P n-1 Indicates the pressure value at the cross section where the nth sampling point is located, △P n1 Indicates the pressure value consumed by the fluid flowing from sampling point n-1 to sampling point n, △P n1 The calculation formula is:

[0013] △P n1 =f(V n / V n内 )·V n内 ·V n内 / (L x·L y )

[0014] In the above formula, V n 、V n内 are the air flow velocity at sampling point n in the public air supply duct and the gas flow velocity in the indoor air supply duct on the nth floor, respectively. The function f(V n / V n内 ) is about the variable V n / V n内 A cubic polynomial function of x , L y are the length and width of the inner section of the public air supply duct respectively;

[0015] f(V n / V n内 )=K1+A1·(V n / V n内 )+B1·(V n / V n内 ) 2 +C1·(V n / V n内 ) 3 , where K1, A1, B1, and C1 are pre-

[0016] Let constant be;

[0017] △P yn is the resistance loss along the public air supply duct:

[0018] △P yn =λ1·ρ·Q n 2 ·h*(L x +L y ) / [4·(L x ·L y ) 3 ]

[0019] In the above formula, λ1 is the resistance coefficient along the public air supply duct, which is a preset value, ρ is the air density, Q n is the exhaust volume of the range hood in the kitchen on the nth floor, h is the floor height, L x , L y are the length and width of the inner section of the public air supply duct respectively;

[0020] Through iterative calculation, using P0=P1+△P 11 +△P y1 , calculate P1, P2...P respectively N ;

[0021] Step 2: Calculate the internal pressure value of the indoor air supply duct in the kitchen of each floor using the following formula:

[0022] P n内 =P n-1 -△P n2

[0023] In the above formula, n-1 Indicates the pressure value at the cross section where the n-1th sampling point is located, P n内 is the pressure value in the indoor air supply duct on the nth floor, △P n2 Indicates the total pressure difference between the section where the n-1th sampling point is located in the public air supply duct and the indoor air supply duct on the nth floor:

[0024] △P n2 =F(V n / V n内 )·V n内 ·V n内

[0025] F(V n / V n内 ) is about the variable V n / V n内 A cubic polynomial function of :

[0026] F(V n / V n内 )=K2+A2·(V n / V n内 )+B2·(V n / V n内 ) 2 +C2·(V n / V n内 ) 3 , where K2, A2, B2, and C2 are preset constants;

[0027] Step 3: Calculate the static pressure value in the kitchen of each floor using the following formula:

[0028] P n厨房 =P n内 -P n动 -△P F -△P g

[0029] P n厨房 P represents the static pressure value in the kitchen of the nth floor resident. n动 =0.5·ρ·V n内 ·V n内 , ρ is the air density, △P F Indicates the pressure loss consumed by the fluid passing through the air supply electric valve, △P F =k1e k2 · (90-θ) ·(ρ·V n内 2 / 2), k1 and k2 are constants, θ is the opening angle of the electric air supply valve on the nth floor, and the initial value of θ is equal to 90°; △P g Indicates the resistance loss that the airflow needs to overcome from the outlet of the electric air supply valve to the kitchen, △P g =k·Q n 2 , k is the resistance coefficient of the indoor air supply pipe and air supply port, which is a preset constant; Q n is the exhaust volume of the range hood in the kitchen on the nth floor;

[0030] Step 4, judge |P n厨房 | Is it less than or equal to 3Pa? If P n厨房 If the opening angle θ of the electric valve for supplying air on the nth floor is less than -3Pa, determine whether it is less than 90°. If not, return to step 1 directly. If so, increase the opening angle of the electric valve for supplying air on the nth floor by 0.2°, and then return to step 1. If P n厨房 If it is greater than 3Pa, reduce the opening angle of the electric air supply valve on the nth floor by 0.2°, and then return to step 1; if |P n厨房 | Less than or equal to 3Pa, go to step 5;

[0031] Step 5. Determine whether the number of supply air electric valves on all household floors whose final opening angle is equal to 90° is greater than 1. If not, reduce the value of P0 by 2 units and then return to step 1. If so, the calculation is completed, and the supply air system sends the final calculated opening angle of the supply air electric valve in each household on each floor to the indoor control box inside the kitchen on the nth floor. At the same time, the supply air volume that the supply air system needs to deliver is adjusted according to the final calculated P0, and the pressure data fed back by the pressure sensor at the inlet of the public supply air duct is used to make the pressure value at the inlet of the public supply air duct obtain the final calculated P0 value.

[0032] The air supply vents can be arranged on the ceiling of each household's kitchen, or on a wall or a cabinet.

[0033] The air supply system is preferably installed in the basement of the building, which can make good use of the characteristics of the basement being warm in winter and cool in summer. It also solves the problem of outdoor rainwater being easily sucked into the kitchen.

[0034] The air supply system includes an air supply fan, an air supply electronic control system, an air supply box and a purification filter, wherein the air supply fan is arranged in the air supply box, and the air supply box is provided with an air inlet and an air outlet, and the purification filter is arranged at the air inlet. The air supply electronic control system is electrically connected to the air supply fan and can control the air volume of the air supply fan, and the air outlet of the air supply box is connected to the inlet of the public air supply duct.

[0035] The roof is also provided with an outdoor auxiliary smoke exhaust system, and the outlet at the top of the public smoke exhaust duct is communicated with the inlet of the outdoor auxiliary smoke exhaust system.

[0036] Smoke exhaust electric valves are installed inside or at the exits of the indoor smoke exhaust ducts of residents on all floors. The indoor smoke exhaust electric valves of residents on each floor are communicated with the indoor electric control boxes on the corresponding floors.

[0037] Compared with the existing technology, the advantages of the present invention are as follows: from the perspective of the overall system architecture, by adding a supply air system and balancing the supply air, the supply air volume of the supply air system is determined according to the exhaust volume of the indoor range hood. The two are equal, which can achieve undisturbed indoor temperature. In addition, the range hoods with DC frequency conversion are used indoors and adopt a constant air volume control method. The air volume can be adjusted by adjusting the rotation speed of the range hoods on each floor, achieving balanced air volume on each floor. At the same time, the exhaust volume can be very accurately converted based on the rotation speed, and then the supply air volume can be determined. This method can effectively solve the problems of small exhaust volume and inaccurate exhaust volume acquisition. By controlling the exhaust volume balance of the entire exhaust duct system, the rated pressure requirement of the outdoor supply air host and the adjustment accuracy requirement of the electric valve can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 This is a structural diagram of a centralized smoke exhaust and air supply system for a building in an embodiment of the present invention.

[0039] Figure 2 This is a schematic diagram of the arrangement structure of the upper and lower sampling points in the public air supply duct corresponding to the nth floor and the indoor air supply duct on the nth floor in an embodiment of the present invention.

[0040] Figure 3 This is a flow chart of the operation control when the indoor range hood adopts constant air volume control in an embodiment of the present invention.

[0041] Figure 4 This is a flow chart of the operation control of the air supply system in an embodiment of the present invention. DETAILED DESCRIPTION

[0042] The present invention will be described in further detail below with reference to the accompanying drawings and embodiments.

[0043] like Figure 1The centralized smoke exhaust and air supply system of the building shown in the figure includes indoor range hoods 11, ... 1N, which are installed in the kitchens of each resident in the building, a public smoke exhaust duct 2 installed in the building, a public air supply duct 3 installed in the building, an air supply system 4, and an outdoor auxiliary smoke exhaust system 21 installed on the top of the building; wherein the air supply system 4 is installed in the basement 10 of the building, and the air supply system 4 includes an air supply fan 41, an air supply electronic control system 4 2. Supplementary air box 43 and purification filter 44, wherein the supplementary air fan 41 is arranged in the supplementary air box 43, the supplementary air box 43 is provided with an air inlet and an air outlet, the purification filter 44 is arranged at the air inlet, the supplementary air electric control system 42 is electrically connected to the supplementary air fan 41 and can control the air volume of the supplementary air fan, the air outlet of the supplementary air box 43 is connected to the inlet of the public supplementary air duct 3; the public exhaust duct 2 and the public supplementary air duct 3 are independently arranged, and the public supplementary air duct is L in length and L in width respectively. x , L y Rectangular pipe; the air outlets of the indoor range hoods 11, ... 1N inside the kitchens of each household in the building are connected to the public exhaust duct 2 through the indoor exhaust pipes 51, ... 5N; the outlets of the indoor exhaust pipes 51, ... 5N inside the residents on each floor are provided with exhaust electric valves 101, ... 10N; the kitchens of each household in the building are provided with air supply ports 71, ... 7N, which are arranged on the ceilings of the kitchens of each household, and the air supply ports are connected to the public air supply duct 3 through indoor air supply ducts 91, ... 9N; the entrances of the indoor air supply ducts 91, ... 9N are provided with air supply electric valves 81, ... 8N with adjustable opening angles; at the same time, the kitchens of each household in the building are provided with air supply ports 71, ... 7N, which are arranged on the ceilings of the kitchens of each household, and the air supply ports are connected to the public air supply duct 3 through indoor air supply ducts 91, ... 9N; the entrances of the indoor air supply ducts 91, ... 9N are provided with air supply electric valves 81, ... 8N with adjustable opening angles Indoor control boxes 61, ...6N are also provided. The indoor range hoods 11, ...1N inside different residents' kitchens are respectively communicated with the indoor control boxes 61, ...6N inside the corresponding residents' kitchens. The indoor control boxes 61, ...6N inside all residents' kitchens are communicated with the air supply electric control system 42. The indoor control boxes 61, ...6N inside all residents' kitchens are communicated with the air supply electric control system 42 and are also communicated with the outdoor auxiliary smoke exhaust system 21. In addition, the air supply electric valves 81, ...8N and the smoke exhaust electric valves 101, ...10N in the users' rooms on each floor are communicated with the indoor control boxes 61, ...6N on the corresponding floors.

[0044] In this embodiment, all indoor range hoods 11, ... 1N are DC variable frequency range hoods, and all indoor range hoods 11, ... 1N are operated in a constant air volume control mode, that is, all indoor range hoods are pre-set with a functional relationship between the fan speed and exhaust volume at different operating gears: Q = A + B*n + C*n 2, where A, B, and C are preset constants, and n is the fan speed of the indoor range hood. When the indoor range hood in a household's kitchen is turned on, the actual exhaust volume Q of the indoor range hood is calculated based on the operating gear selected by the user and the current fan operating speed n. Then, the real-time operating gear of the indoor range hood is adjusted according to the actual exhaust volume Q and the target exhaust volume range. If the actual exhaust volume Q is greater than the maximum value of the target exhaust volume range, the operating gear of the indoor range hood is reduced. Conversely, if the actual exhaust volume Q is greater than the maximum value of the target exhaust volume range, the operating gear of the indoor range hood is reduced. If the actual exhaust volume Q is less than the minimum value of the target exhaust volume range, the operating gear of the indoor range hood is increased; if the actual exhaust volume Q is within the target exhaust volume range, the operating gear of the indoor range hood is maintained unchanged; in addition, the indoor control box on the powered-on floor also sends the location information and actual exhaust volume of the indoor range hoods on the corresponding floor to the outdoor auxiliary smoke exhaust system. The outdoor auxiliary smoke exhaust system controls the operating speed of the fans in the outdoor auxiliary smoke exhaust system based on the power-on rate of the indoor range hoods and the actual exhaust volume of all indoor range hoods;

[0045] The indoor control boxes 61, ... 6N and the air supply electric control system 42 are configured as follows: when the indoor range hood inside a certain household's kitchen is turned on, the indoor control box inside the corresponding household's kitchen obtains the actual exhaust volume Q of the indoor range hood and sends it to the air supply system 42 in real time; the air supply electric control system 42 controls the air supply volume output by the air supply fan 41 according to the sum of the actual exhaust volumes of all turned-on indoor range hoods, and at the same time sends a control instruction to the indoor control box inside the corresponding household's kitchen; the indoor control box inside the corresponding household's kitchen controls the opening angle of the corresponding air supply electric valve, so that the air intake volume entering the corresponding household's kitchen is the same as the exhaust volume of the indoor range hood inside the corresponding household's kitchen.

[0046] In this embodiment, a pressure sensor 31 is provided at the entrance of the common air supply duct, and the pressure sensor 31 is communicatively connected to the air supply electronic control system 42 of the air supply system. When the indoor range hood inside a certain household's kitchen is turned on, the indoor control box inside the corresponding household's kitchen obtains the actual exhaust volume of the indoor range hood and sends it to the air supply system in real time. At the same time, the indoor control box inside the corresponding household's kitchen controls the air supply electric valve in the household from a closed state to an open state, and adjusts the opening angle of the air supply electric valve in the household to 90°. At the same time, the indoor range hood automatically obtains the current fan speed value, and calculates the actual exhaust volume Q based on the speed value. The electronic control system of the indoor range hood determines whether the current actual exhaust volume Q is within the target air volume range Q0±△Q under the corresponding operating gear. If it is too large, the input operating gear is reduced. If it is too small, the input operating gear is increased until the actual exhaust volume of the range hood is stable. Figure 3As shown, the indoor range hood sends the current actual exhaust volume to the indoor control box, and the indoor control box then sends the startup floor information and the actual exhaust volume information to the supply air system and the outdoor auxiliary smoke exhaust system; the outdoor auxiliary smoke exhaust system adjusts the operating speed of the outdoor auxiliary smoke exhaust system according to the startup rate of the indoor range hood and the total exhaust volume; the supply air system sets the initial pressure value at the inlet of the public supply air duct according to the startup rate of the indoor range hood, and assigns the initial pressure value to P0, and then executes the following control steps, Figure 4 As shown:

[0047] Step 1: Select N sampling points from bottom to top inside the public air supply duct, and record the pressure values at the sections where these N sampling points are located as P1, P2, ... P n-1 , P n , ... P N The first sampling point and the second sampling point are located at the upper and lower sides of the first-floor household air supply inlet or the indoor air supply duct inlet, respectively. The n-1th sampling point and the nth sampling point are located at the upper and lower sides of the n-floor household air supply inlet or the indoor air supply duct inlet, respectively. The N-1th sampling point and the Nth sampling point are located at the upper and lower sides of the N-floor household air supply inlet or the indoor air supply duct inlet, respectively. N is the total number of floors of the building. The pressure value at the cross section of each sampling point in the public air supply duct is then calculated using the following formula:

[0048] P n-1 =P n +△P n1 +△P yn

[0049] In the above formula, P n-1 Indicates the pressure value at the cross section where the n-1th sampling point is located, P n-1 Indicates the pressure value at the cross section where the nth sampling point is located, Figure 2 As shown, △P n1 Indicates the pressure value consumed by the fluid flowing from sampling point n-1 to sampling point n, △P n1 The calculation formula is:

[0050] △P n1 =f(V n / V n内 )·V n内 ·V n内 / (L x ·L y )

[0051] In the above formula, V n 、V n内 are the air flow velocity at sampling point n in the public air supply duct and the gas flow velocity in the indoor air supply duct on the nth floor, respectively. The function f(Vn / V n内 ) is about the variable V n / V n内 A cubic polynomial function of x , L y are the length and width of the inner section of the public air supply duct respectively;

[0052] f(V n / V n内 )=K1+A1·(V n / V n内 )+B1·(V n / V n内 ) 2 +C1·(V n / V n内 ) 3 , where K1, A1, B1, and C1 are preset constants;

[0053] △P yn is the resistance loss along the public air supply duct:

[0054] △P yn =λ1·ρ·Q n 2 ·h*(L x +L y ) / [4·(L x ·L y ) 3 ]

[0055] In the above formula, λ1 is the resistance coefficient along the public air supply duct, which is a preset value, ρ is the air density, Q n is the exhaust volume of the range hood in the kitchen on the nth floor, h is the floor height, L x , L y are the length and width of the inner section of the public air supply duct respectively;

[0056] Through iterative calculation, using P0=P1+△P 11 +△P y1 , calculate P1, P2...P respectively N ;

[0057] Step 2: Calculate the internal pressure value of the indoor air supply duct in the kitchen of each floor using the following formula:

[0058] P n内 =P n-1 -△P n2

[0059] In the above formula, n-1 Indicates the pressure value at the cross section where the n-1th sampling point is located, P n内is the pressure value in the indoor air supply duct on the nth floor, △P n2 Indicates the total pressure difference between the section where the n-1th sampling point is located in the public air supply duct and the indoor air supply duct on the nth floor:

[0060] △P n2 =F(V n / V n内 )·V n内 ·V n内

[0061] F(V n / V n内 ) is about the variable V n / V n内 A cubic polynomial function of :

[0062] F(V n / V n内 )=K2+A2·(V n / V n内 )+B2·(V n / V n内 ) 2 +C2·(V n / V n内 ) 3 , where K2, A2, B2, and C2 are preset constants;

[0063] Step 3: Calculate the static pressure value in the kitchen of each floor using the following formula:

[0064] P n厨房 =P n内 -P n动 -△P F -△P g

[0065] P n厨房 P represents the static pressure value in the kitchen of the nth floor resident. n动 =0.5·ρ·V n内 ·V n内 , ρ is the air density, △P F Indicates the pressure loss consumed by the fluid passing through the air supply electric valve, △P F =k1e k2 · (90-θ) ·(ρ·V n内 2 / 2), k1 and k2 are constants, θ is the opening angle of the electric valve for supplying air on the nth floor, and the initial value of θ is 90°; △P g Indicates the resistance loss that the airflow needs to overcome from the outlet of the electric air supply valve to the kitchen, △P g =k·Q n 2, k is the resistance coefficient of the indoor air supply pipe and air supply port, which is a preset constant; Q n is the exhaust volume of the range hood in the kitchen on the nth floor;

[0066] Step 4, judge |P n厨房 | Is it less than or equal to 3Pa? If P n厨房 If the opening angle θ of the electric valve for supplying air on the nth floor is less than -3Pa, determine whether it is less than 90°. If not, return to step 1 directly. If so, increase the opening angle of the electric valve for supplying air on the nth floor by 0.2°, and then return to step 1. If P n厨房 If it is greater than 3Pa, reduce the opening angle of the electric air supply valve on the nth floor by 0.2°, and then return to step 1; if |P n厨房 | Less than or equal to 3Pa, go to step 5;

[0067] Step 5. Determine whether the number of supply air electric valves on all household floors whose final opening angle is equal to 90° is greater than 1. If not, reduce the value of P0 by 2 units and then return to step 1. If so, the calculation is completed, and the supply air system sends the final calculated opening angle of the supply air electric valve in each household on each floor to the indoor control box inside the kitchen on the nth floor. At the same time, the supply air volume that the supply air system needs to deliver is adjusted according to the final calculated P0, and the pressure data fed back by the pressure sensor at the inlet of the public supply air duct is used to make the pressure value at the inlet of the public supply air duct obtain the final calculated P0 value.

[0068] Below, take a building with 30 floors as an example. The public smoke exhaust duct is a rectangular duct with an internal length and width of 500mm and 400mm respectively, and the public supply air duct is a rectangular duct with an internal length and width of 350mm and 300mm respectively. The floor height is 3m. For example, if there are currently 9 households cooking, namely on the 1st, 4th, 6th, 11th, 15th, 19th, 23rd, 26th, and 30th floors, two conditions are selected for comparison: one is to install a conventional range hood (maximum air volume 18m3 / min, maximum static pressure 400Pa) indoors, and the other is to install the DC variable frequency range hood of this embodiment and operate it in constant air volume control mode, and install an outdoor auxiliary smoke exhaust system on the roof. It can be seen from the two tables below that the DC variable frequency range hood using the constant air volume control method in this embodiment has many advantages in terms of both smoke exhaust effect and air supply control: 1. The exhaust volume on low floors can be greatly improved; 2. The angle adjustment of the electric air supply valve on low floors is increased from more than 50 degrees to more than 66 degrees, which greatly reduces the angle control accuracy requirements of the electric air supply valve, and the startup noise of the air flow through the electric air supply valve will also be greatly reduced; 3. Under the same common air supply duct size, the DC variable frequency range hood using the constant air volume control method in this embodiment can actually reduce the inlet static pressure value P0 value when the total air supply volume is greatly increased, which can also further reduce the performance requirements of the fan in the air supply system.

[0069]

[0070]

[0071]

Claims

1. A centralized smoke exhaust and air supply system for a building, characterized by: The utility model comprises an indoor range hood arranged inside the kitchen of each household in the building, a public smoke exhaust duct arranged inside the building, a public air supply duct arranged inside the building, and an air supply system. An outdoor auxiliary smoke exhaust system is also provided on the roof, and the outlet at the top of the public smoke exhaust duct is connected with the inlet of the outdoor auxiliary smoke exhaust system; wherein the public smoke exhaust duct and the public air supply duct are arranged independently of each other, and the air outlet of the air supply system is connected with the inlet of the public air supply duct. An air supply port is provided inside the kitchen of each household in the building, and the air supply port is connected with the public air supply duct directly or through the indoor air supply duct. An electric air supply valve with an adjustable opening angle is provided at the air supply inlet or at the inlet or outlet of the indoor air supply duct; the air outlet of the indoor range hood inside each resident's kitchen in the building is connected to the public exhaust duct through an indoor smoke exhaust pipe; in addition, an indoor control box is also provided inside each resident's kitchen in the building, and the indoor range hoods and electric air supply valves inside different resident's kitchens are all communicatively connected to the indoor control box inside the corresponding resident's kitchen, and the indoor control boxes inside all resident's kitchens are all communicatively connected to the air supply system, and the indoor control boxes inside all resident's kitchens are also communicatively connected to the outdoor auxiliary smoke exhaust system; All indoor range hoods are DC variable frequency range hoods, and all indoor range hoods are operated in a constant air volume control mode, that is, all indoor range hoods are pre-set with the functional relationship between the fan speed and exhaust volume under different operating gears: Q = A + B*n + C*n 2 , where A, B, and C are preset constants, and n is the fan speed of the indoor range hood. When the indoor range hood in a household's kitchen is turned on, the actual exhaust volume Q of the indoor range hood is calculated based on the operating gear selected by the user and the current fan operating speed n. The real-time operating gear of the indoor range hood is then adjusted based on the actual exhaust volume Q and the target exhaust volume range. If the actual exhaust volume Q is greater than the maximum value of the target exhaust volume range, the operating gear of the indoor range hood is reduced. On the contrary, if the actual exhaust volume Q is less than the minimum value of the target exhaust volume range, the operating gear of the indoor range hood is increased; If the actual exhaust volume Q is within the target exhaust volume range, the operating gear of the indoor range hood is maintained unchanged; The indoor control box and the air supply system are configured as follows: when the indoor range hood inside a certain household's kitchen is turned on, the indoor control box inside the corresponding household's kitchen obtains the actual exhaust volume Q of the indoor range hood and sends it to the air supply system in real time; the air supply system controls the output air supply volume according to the sum of the actual exhaust volumes of all turned-on indoor range hoods, and at the same time sends a control instruction to the indoor control box inside the corresponding household's kitchen; the indoor control box inside the corresponding household's kitchen controls the opening angle of the corresponding air supply electric valve, so that the air intake volume entering the corresponding household's kitchen is the same as the exhaust volume of the indoor range hood inside the corresponding household's kitchen.

2. The centralized smoke exhaust and air supply system for buildings according to claim 1 is characterized in that: The air supply inlets inside the households on each floor are connected to the public air supply duct through the indoor air supply duct; the public air supply duct is L in length and L in width respectively. x , L y a rectangular parallelepiped pipe; a pressure sensor is provided at the inlet of the common air supply duct, and the pressure sensor is in communication with the air supply system; when the indoor range hood in a certain household's kitchen is turned on, the indoor control box in the corresponding household's kitchen obtains the exhaust volume of the indoor range hood and sends it to the air supply system in real time, and at the same time, the indoor control box in the corresponding household's kitchen controls the air supply electric valve in the household from a closed state to an open state, and adjusts the opening angle of the air supply electric valve in the household to 90°. The air supply system sets an initial pressure value at the inlet of the common air supply duct according to the start-up rate of the indoor range hood, and assigns the initial pressure value to P0, and then executes the following control steps: Step 1: Select N sampling points from bottom to top inside the public air supply duct, and record the pressure values at the sections where these N sampling points are located as P1, P2, ... P n-1 , P n , ... P N The first sampling point and the second sampling point are located at the upper and lower sides of the first-floor household air supply inlet or the indoor air supply duct inlet, respectively. The n-1th sampling point and the nth sampling point are located at the upper and lower sides of the n-floor household air supply inlet or the indoor air supply duct inlet, respectively. The N-1th sampling point and the Nth sampling point are located at the upper and lower sides of the N-floor household air supply inlet or the indoor air supply duct inlet, respectively. N is the total number of floors of the building. The pressure value at the cross section of each sampling point in the public air supply duct is then calculated using the following formula: P n-1 =P n +△P n1 +△P yn In the above formula, P n-1 Indicates the pressure value at the cross section where the n-1th sampling point is located, P n-1 Indicates the pressure value at the cross section where the nth sampling point is located, △P n1 Indicates the pressure value consumed by the fluid flowing from sampling point n-1 to sampling point n, △P n1 The calculation formula is: △P n1 =f(V n / V n内 )·V n内 ·V n内 / (L x ·L y ) In the above formula, V n 、V n内 are the air flow velocity at sampling point n in the public air supply duct and the gas flow velocity in the indoor air supply duct on the nth floor, respectively. The function f(V n / V n内 ) is about the variable V n / V n内 A cubic polynomial function of L x , L y are the length and width of the inner section of the public air supply duct respectively; f(V n / V n内 )=K1+A1·(V n / V n内 )+B1·(V n / V n内 ) 2 +C1·(V n / V n内 ) 3 , where K1, A1, B1, and C1 are pre- Let constant be; △P yn is the resistance loss along the public air supply duct: △P yn =λ1·ρ·Q n 2 ·h*(L x +L y ) / [4·(L x ·L y ) 3 ] In the above formula, λ1 is the resistance coefficient along the public air supply duct, which is a preset value, ρ is the air density, Q n is the exhaust volume of the range hood in the kitchen on the nth floor, h is the floor height, L x , L y are the length and width of the inner section of the public air supply duct respectively; Through iterative calculation, using P0=P1+△P 11 +△P y1 , calculate P1, P2...P respectively N ; Step 2: Calculate the internal pressure value of the indoor air supply duct in the kitchen of each floor using the following formula: P n内 =P n-1 -△P n2 In the above formula, n-1 Indicates the pressure value at the cross section where the n-1th sampling point is located, P n内 is the pressure value in the indoor air supply duct on the nth floor, △P n2 Indicates the total pressure difference between the section where the n-1th sampling point is located in the public air supply duct and the indoor air supply duct on the nth floor: △P n2 =F(V n / V n内 )·V n内 ·V n内 F(V n / V n内 ) is about the variable V n / V n内 A cubic polynomial function of : F(V n / V n内 )=K2+A2·(V n / V n内 )+B2·(V n / V n内 ) 2 +C2·(V n / V n内 ) 3 , where K2, A2, B2, and C2 are Preset constants; Step 3: Calculate the static pressure value in the kitchen of each floor using the following formula: P n厨房 =P n内 -P n动 -△P F -△P g P n厨房 P represents the static pressure value in the kitchen of the nth floor resident. n动 =0.5·ρ·V n内 ·V n内 , ρ is the air density, △P F Indicates the pressure loss consumed by the fluid passing through the air supply electric valve, △P F =k1e k2 · (90-θ) ·(ρ·V n内 2 / 2), k1 and k2 are constants, θ is the opening angle of the electric valve for supplying air on the nth floor, and the initial value of θ is 90°; △P g Indicates the resistance loss that the airflow needs to overcome from the outlet of the electric air supply valve to the kitchen, △P g =k·Q n 2 , k is the resistance coefficient of the indoor air supply pipe and air supply port, which is a preset constant; Q n is the exhaust volume of the range hood in the kitchen on the nth floor; Step 4, judge |P n厨房 | Is it less than or equal to 3Pa? If P n厨房 If the opening angle θ of the electric valve for supplying air on the nth floor is less than -3Pa, determine whether it is less than 90°. If not, return to step 1 directly. If so, increase the opening angle of the electric valve for supplying air on the nth floor by 0.2°, and then return to step 1. If P n厨房 If it is greater than 3Pa, reduce the opening angle of the electric air supply valve on the nth floor by 0.2°, and then return to step 1; if |P n厨房 | Less than or equal to 3Pa, go to step 5; Step 5: Determine whether the number of air supply electric valves with a final opening angle of 90° on all residential floors is greater than 1. If not, reduce the value of P0 by 2 units and return to step 1. If so, the calculation is completed, and the air supply system sends the final calculated opening angle of the air supply electric valve in each floor to the indoor control box inside the kitchen on the nth floor; at the same time, the air supply system adjusts the amount of air supply that needs to be delivered according to the final calculated P0, and uses the pressure data fed back by the pressure sensor at the inlet of the public air supply duct to make the pressure value at the inlet of the public air supply duct obtain the final calculated P0 value.

3. The centralized smoke exhaust and air supply system for buildings according to claim 1 is characterized in that: The air supply vents are arranged on the ceiling, wall or cabinet of each household's kitchen.

4. The centralized smoke exhaust and air supply system for buildings according to claim 1 is characterized in that: The air supply system is arranged in the basement of the building.

5. The centralized smoke exhaust and air supply system for buildings according to claim 4 is characterized in that: The air supply system includes an air supply fan, an air supply electronic control system, an air supply box and a purification filter, wherein the air supply fan is arranged in the air supply box, and the air supply box is provided with an air inlet and an air outlet, and the purification filter is arranged at the air inlet. The air supply electronic control system is electrically connected to the air supply fan and can control the air volume of the air supply fan, and the air outlet of the air supply box is connected to the inlet of the public air supply duct.

6. The centralized smoke exhaust and air supply system for buildings according to claim 1 is characterized in that: Smoke exhaust electric valves are installed inside or at the exits of the indoor smoke exhaust ducts of residents on all floors. The indoor smoke exhaust electric valves of residents on each floor are communicated with the indoor electric control boxes on the corresponding floors.

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