A digital commissioning method for a ventilation system combined with a BIM model

Abstract

The present invention relates to the field of digital commissioning technology, and discloses a digital commissioning method for a ventilation system combined with a BIM model, including the following steps: Step 1: Design link; Step 2: Construction link; Step 3: Draw the pressure drop curve of the air volume regulating valve; Step 4: Commissioning review. This digital commissioning method for the ventilation system combined with the BIM model improves the adjustment efficiency by about 25% in the initial commissioning link of the ventilation system before project completion, and at the same time improves the accuracy of system commissioning. Compared with manual repetitive work, this patent utilizes the characteristic of the large computing power of the computer to avoid manual repetition in the commissioning process and increase work efficiency. By using computer modeling, collecting and processing the data of the ventilation system, and the operation of the data model can have a preliminary deduction of the operation state of the ventilation system, which can provide a reference basis for the operation state monitoring of the ventilation system.

Description

Technical Field

[0001] The present invention relates to the technical field of digital commissioning, and particularly to a digital commissioning method for a ventilation system combined with a BIM model. Background Art

[0002] Ventilation is a building environment control technology that controls the spread and harm of air pollutants by means of dilution through ventilation or ventilation removal, etc., to ensure the indoor and outdoor air environmental quality. The ventilation system is a set of devices that realizes this function, including air inlets, air outlets, air supply ducts, fans, cooling and heating, filters, control systems, and other auxiliary equipment.

[0003] As a system for air flow, the ventilation system is indispensable for building construction. Especially in high-rise buildings, in order to ensure the normal air flow inside the building and keep the indoor air environment clean, the ventilation system itself is used in cooperation with a series of mechanical and electrical systems and related equipment. Its hardware essence is mechanical equipment and electromechanical equipment;

[0004] During the construction process of a building project, in order to ensure that the work of each mechanical and electrical system of the building is in the best state and meets the usage requirements of the owner, the mechanical and electrical construction unit needs to conduct system commissioning before project delivery, which is also one of the necessary contents in the project completion acceptance report. Currently, this part of the work is still mainly achieved by the experience of on-site technical personnel through repeated commissioning. This method has the following three problems:

[0005] First, the repeated workload is time-consuming and laborious;

[0006] Second, the accuracy of the commissioning result data is not high, and it is difficult to support projects with high system operation requirements (such as negative pressure rooms, rooms with noise control requirements, etc.);

[0007] Third, there are certain safety hazards. For example, during the commissioning measurement process, personnel need to climb up and down, which has labor risks;

[0008] Therefore, a digital commissioning method for a ventilation system combined with a BIM model is proposed to solve the above-mentioned problems. Summary of the Invention

[0009] (1) Technical Problems to be Solved

[0010] Aiming at the deficiencies of the prior art, the present invention provides a digital commissioning method for a ventilation system combined with a BIM model, which solves the problems of many inconveniences existing in the existing manual commissioning.

[0011] (2) Technical Solutions

[0012] The technical solution of the present invention to solve the above technical problems is as follows: A digital commissioning method for a ventilation system combined with a BIM model, comprising the following steps:

[0013] Step 1: Design stage, design according to the project to be constructed, perform 3D modeling through Revit software, determine relevant data, perform hydraulic balance calculations, and add air volume regulating valves to the official website of the system.

[0014] Step 2: Construction stage, the construction unit performs construction operations, adjusts the ventilation system pipe network and even the duct size according to the actual construction environment on site, and records the actual data.

[0015] Step 3: Calculate the pressure loss through a formula, record the numerical value, draw the pressure drop curve of the air volume regulating valve, and input the drawn curve into the MagiCAD software.

[0016] Step 4: Debug and review the actual data and design parameters through the debugging process.

[0017] The beneficial effects of the present invention are:

[0018] 1), In the initial commissioning stage of the ventilation system before project completion, the digital commissioning method for the ventilation system combined with the BIM model improves the adjustment efficiency by about 25%, improves the accuracy of system commissioning, and compared with manual repetitive work, this patent utilizes the characteristic of large computing power of the computer to avoid manual repetition in the commissioning process and increase work efficiency.

[0019] 2), The digital commissioning method for the ventilation system combined with the BIM model collects and processes the data of the ventilation system by using computer modeling, and the operation of the data model can preliminarily deduce the operation state of the ventilation system, providing a reference basis for the operation state monitoring of the ventilation system in the project use and operation and maintenance stage, and also providing relatively detailed data reference for other projects with high precision requirements for other parameters.

[0020] On the basis of the above technical solution, the present invention can also be improved as follows.

[0021] Further, the relevant data includes but is not limited to the air volume of the unit, the total / static pressure value of the unit, the designed air volume of the air outlet, the roughness of the air duct of the ventilation system, and the pipe size.

[0022] A. Further, the pressure loss of the air duct:

[0023] ΔP = ΔP m +ΔP j

[0024] B. Frictional pressure loss along the duct: The frictional loss ΔP along the duct m (Pa) is calculated as follows: a )

[0025] ΔP m = Δp m l

[0026] where Δp m --- Frictional resistance per unit duct length, Pa / m; a / m;

[0027] l --- Duct length, m;

[0028] The frictional resistance per unit duct length Δp m is calculated as follows:

[0029]

[0030] where λ --- Friction resistance coefficient;

[0031] ρ --- Air density, kg / m 3 ;

[0032] d e --- Equivalent diameter of the duct, m;

[0033] C. Local pressure loss of the duct, the pressure loss ΔP i (Pa) is calculated as follows:

[0034]

[0035] where --- Local resistance coefficient;

[0036] V --- Air velocity at the location where the local pressure loss in the duct occurs, m / s;

[0037] ρ --- Air density, kg / m 3 .

[0038] Furthermore, the debugging process is as follows:

[0039] a) Preparation stage: Perform calculation and analysis through MagiCAD software. This calculation and analysis is based on the pressure reduction curve graph to obtain the corresponding valve opening values at different pressures;

[0040] b) Model stage: Revise and update the Revit model of the project according to the actual on-site construction situation;

[0041] c) Data confirmation stage: Confirm the duct materials used on-site to determine the duct roughness; confirm the designed air volume of the air outlets on-site; confirm the unit parameters on-site and assign them to the model using MagiCAD software;

[0042] d) Simulation operation analysis stage: Through the simulation operation analysis of MagiCAD, obtain the opening values of different valves, assign them to the model, and mark them on the drawings;

[0043] e) On-site commissioning guidance stage: Use the valve opening marked on the drawings to guide the on-site ventilation system commissioning work and record the results;

[0044] f) Data provision for the system operation monitoring platform: Import the model containing the actual air volume of the air outlets, the static pressure at the outlet of the air outlets, and the pressure loss data of the air valves into the system operation monitoring platform. These data are the benchmark values during the normal operation of the system; Set a deviation threshold. When the data monitored by the on-site IoT devices exceeds the deviation, an alarm prompt can be given on the system operation monitoring platform. Description of the Drawings

[0045] Figure 1 It is a schematic diagram of the process of the present invention;

[0046] Figure 2 It is a pressure drop curve diagram of the present invention. Detailed Embodiment

[0047] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0048] In the embodiment:

[0049] Refer to Figure 1-2 , a digital commissioning method for a ventilation system combined with a BIM model. The present invention includes the following steps:

[0050] Step 1: Design link. Design according to the project to be constructed, perform three-dimensional modeling through Revit software, determine relevant data, perform hydraulic balance calculations, and add air volume regulating valves to the official website of the system;

[0051] The ultimate goal of this step is to obtain a reference for the unit selection scheme of the ventilation system. Therefore, only the maximum value of the pressure loss of the valve is considered in this environment, and the adjustment ability of the valve itself is not considered;

[0052] Step 2: Construction stage. The construction unit conducts construction operations, adjusts the ventilation system pipeline network and even the duct size according to the actual on-site construction environment, and records the actual data;

[0053] This step will be adjusted according to the actual on-site construction conditions, plan changes and space management requirements. Since the ventilation system units finally installed in the project are specified or directly purchased by the Party A, there will be significant differences between the parameters of the actual units and the reference data for unit selection by the design institute. Therefore, it is necessary for the construction unit to control the air volume regulating valve on-site to ensure that the design conditions of the room are met;

[0054] Step 3: Calculate the pressure loss through a formula (the most intuitive feedback of pressure loss presented to engineers is the valve adjustment value). While recording the numerical value, draw the pressure drop curve of the air volume regulating valve, and input the drawn curve into the MagiCAD software. Through this pressure drop curve graph, calculation and analysis can be carried out in the MagiCAD software to obtain the corresponding valve opening values under different pressure losses;

[0055] When the designed air volume of the air outlet, the roughness of the ventilation system ducts, the pipe size and length are fixed, the frictional pressure loss and the local pressure loss formed by pipe fittings are determined. Only through the control of the air volume regulating valve can the hydraulic balance of the pipeline network be achieved, and the problem of excessive or insufficient air volume at some air outlets caused by hydraulic imbalance be avoided. That is, the pressure loss from the unit to different air outlets, after deducting the frictional pressure loss and the local pressure loss formed by pipe fittings, the remaining difference part will be reflected in the air volume regulating valve;

[0056] Step 4: Conduct debugging and verification on the actual data and design parameters through the debugging process;

[0057] In the construction stage of the actual project, the known conditions are the air volume of the unit, the total pressure / static pressure value of the unit, the designed air volume of the air outlet, the roughness of the ventilation system ducts, the pipe size and length;

[0058] What needs to be obtained as unknown data is the pressure loss of the air volume regulating valve when the air outlet reaches the designed air volume; and the most intuitive feedback of pressure loss presented to the project site engineers is the valve adjustment value, which is also the core data focused on by digital debugging technology;

[0059] Digital debugging technology aims to guide the project site engineers to precisely control the air volume regulating valve through the given specific valve adjustment value, while achieving the designed air volume of the air outlet, improving the debugging efficiency of the project site engineers and the accuracy of debugging;

[0060] Moreover, the technology of the present invention is based on computer digital operations. Therefore, in actual use, it can make full use of the advantages of strong computer computing power, avoid manual repetitive labor, reduce the work cost, and improve the debugging efficiency by about 25% during the initial commissioning of the ventilation system before the project is completed and delivered. At the same time, it improves the debugging accuracy, and avoids the need for personnel to climb up and down during the debugging process, effectively reducing the labor risk of the debugging personnel;

[0061] This patent can perform advance deduction by means of modeling. After the debugging is completed, the debugging data can still be used, providing a reference basis for monitoring the operation status of the ventilation system during the operation and maintenance stage of the project. Moreover, this model can provide effective data reference for the construction of other projects. When the number of project debugging is large enough, it can even directly perform the debugging operation;

[0062] Compared with the single manual debugging method, this patent replaces manual repetitive debugging, converts the original empirical debugging operation into visible data, not only enables a more intuitive understanding of the data during debugging, but also can collect the data for subsequent use. Moreover, this way of standardizing the debugging data is more accurate and replicable than empiricism. Manual debugging based on experience will vary according to factors such as the experience of the workers, their physical condition, and even the equipment model, with low accuracy.

[0063] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the presence of additional identical elements in the process, method, article or device comprising the element.

[0064] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A digital commissioning method for a ventilation system combined with a BIM model, characterized in that, it includes the following steps: Step 1: Design stage, design according to the project to be constructed, perform 3D modeling through Revit software, determine relevant data, perform hydraulic balance calculations, and add air volume regulating valves to the official website of the system; Step 2: Construction stage, the construction unit performs construction operations, adjusts the ventilation system pipe network and even the duct size according to the actual construction environment on site, and records the actual data; Step 3: Calculate the pressure loss through a formula, record the numerical value, draw the pressure drop curve of the air volume regulating valve, and input the drawn curve into the MagiCAD software; Step 4: Debug and review the actual data and design parameters through the debugging process; The formula is as follows: A. Pressure loss of the air duct: ΔP = ΔP m +ΔP j B. Frictional pressure loss along the air duct: The frictional loss ΔP along the air duct m (P a ) is calculated according to the following formula: ΔP m = Δp m l where Δp m --- frictional resistance along the unit pipe length, P a / m; l---Length of the air duct, m; Frictional resistance Δp per unit pipe length m , is calculated by the following formula: Where λ---Friction resistance coefficient; ρ---Air density, kg / m 3 ; d e --- Equivalent diameter of air duct, m; C. Local pressure loss of the air duct, pressure loss ΔP i (Pa), and is calculated according to the following formula: where --- local resistance coefficient; V---Air velocity at the location where the local pressure loss occurs in the air duct, m / s; ρ---Air density, kg / m 3 .

2. A digital commissioning method for a ventilation system combined with a BIM model according to claim 1, characterized in that: The relevant data includes but is not limited to the air volume of the unit, the total / static pressure value of the unit, the designed air volume of the air outlet, the roughness of the air duct of the ventilation system, and the pipe size.

3. A digital commissioning method for a ventilation system combined with a BIM model according to claim 1, characterized in that: The debugging process is as follows: a) Preparation stage: Perform calculation and analysis through MagiCAD software, which is based on the pressure reduction curve graph, so as to obtain the corresponding valve opening values under different pressures; b) Model stage: Modify and update the Revit model of the project according to the actual construction situation on site; c) Data confirmation stage: Confirm the air duct material used on site to determine the air duct roughness; confirm the designed air volume of the air outlets on site; confirm the unit parameters on site and assign them to the model using MagiCAD software; d) Simulation operation analysis stage: Through the simulation operation analysis of MagiCAD, obtain the opening values of different valves, assign them to the model, and mark them on the drawings; e) On-site debugging guidance stage: Use the valve opening marked on the drawings to guide the on-site ventilation system debugging work and record the results; f) Data provision for the system operation monitoring platform: Import the model containing the actual air volume of the air outlet, the residual pressure at the air outlet, and the air valve pressure loss data into the system operation monitoring platform, and these data are the reference values when the system operates normally; Given a deviation threshold, when the data monitored by the on-site IoT device exceeds the deviation, an alarm prompt can be given on the system operation monitoring platform.

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