Method for calculating most unfavorable end of air conditioner pipeline

Abstract

The invention relates to the technical field of calculation methods for the most disadvantageous end of an air conditioner pipeline, and discloses a method for calculating the most disadvantageous end of the air conditioner pipeline, and the method comprises the following steps: S1, erecting a temperature control module at the air outlet end of each pipeline according to the collection condition; wherein the temperature control module comprises a temperature sensor and a pipeline valve; s2, uploading temperature information collected by the temperature control module to an internet management platform during calculation; s3, comparing the temperature information of each pipeline by using the Internet management platform; s4, analyzing the comparison data by using the Internet management platform and taking out an average value; and S5, sending the data information to a control module through the Internet management platform, and controlling each pipeline to be cut off through the control module. The method for calculating the most disadvantageous end of the air conditioner pipeline has the advantages of being convenient to calculate the most disadvantageous end of the air conditioner pipeline and the like, and solves the problem that a resistance calculation method under insufficient development flow still lacks at the present stage.

Description

Technical Field

[0001] The invention relates to the technical field of methods for calculating the most disadvantageous end of an air-conditioning pipeline, and in particular to a method for calculating the most disadvantageous end of an air-conditioning pipeline. Background Art

[0002] The most unfavorable end of the air-conditioning duct is the end where the cooling or heating effect of the air-conditioning duct is the worst in traditional terms. For decades, traditional research on duct resistance has mostly been based on the premise of fully developed flow. However, in the field of ventilation and air-conditioning ducts, the resistance changes caused by non-fully developed flow are significant. In the traditional research of predecessors, due to the need to simplify the research, it is often assumed that the distance between the local fittings of the pipeline is "far enough", so far that the flow fields in the fittings do not interfere with each other, that is, it is assumed that the inlet of the local fittings is "fully developed flow". We can temporarily call the local fittings at this time "single local fittings" (also known as local fittings under "non-coupling conditions" and "non-composite conditions"). Under this condition, the flow field changes inside the local fittings and the resistance problems caused by them are only affected by the deformation of the local fittings themselves; and the flow state in the straight pipe section is fully developed flow. However, in the field of construction, the actual distance between the local fittings is "close enough", so close that the flow fields between adjacent local fittings affect each other, that is, the boundary conditions at the inlet and outlet of the pipeline are "non-fully developed flow";

[0003] Due to the dynamic nature of central air-conditioning water systems, both designers and integrated controllers are striving to accurately determine the location of the most unfavorable pressure point during central air-conditioning design and system integration control. In order to ensure the normal operation of the terminal with the largest demand pressure difference under rated flow, a series of methods have been developed, such as fuzzy control, adaptive control, and adding pressure sensors to each floor. These methods have solved the problem of automatic adaptation of the computer room under constant changes in terminal demand to a certain extent, but the above technologies have not achieved truly precise control.

[0004] In real projects, due to the limitations of building structures, adjacent influences are actually ubiquitous in the construction field. However, at present, there is still a lack of resistance calculation methods for non-fully developed flows. Therefore, a method for calculating the most unfavorable end of air-conditioning pipes is proposed to solve the above-mentioned problems. Summary of the invention

[0005] 1. Technical issues to be resolved

[0006] In view of the shortcomings of the prior art, the present invention provides a method for calculating the most unfavorable end of an air-conditioning duct, which has the advantages of being easy to calculate the most unfavorable end of an air-conditioning duct, and solves the problem that a method for calculating resistance under non-fully developed flow is still missing at this stage.

[0007] (II) Technical solution

[0008] The technical solution of the present invention to solve the above technical problem is as follows: A method for calculating the most unfavorable end of an air conditioning pipeline comprises the following steps:

[0009] Step S1, installing a temperature control module at the air outlet of each pipeline according to the collected situation;

[0010] The temperature control module includes a temperature sensor and a pipeline valve;

[0011] Step S2: Upload the temperature information collected by the temperature control module to the Internet management platform during calculation;

[0012] Step S3: using the Internet management platform to compare the temperature information of each pipeline;

[0013] Step S4: Analyze the comparison data using the Internet management platform to obtain the average value;

[0014] Step S5, sending the data information to the control module through the Internet management platform, and controlling each pipeline to be cut off through the control module;

[0015] Step S6, using the resistance calculation model to obtain the resistance value of each pipeline, and obtaining the resistance value of each pipeline itself according to the pressure drop method;

[0016] The pressure drop method is to obtain the pressure values ​​on the inlet and outlet surfaces of the local component through the results of the software Fluent simulation, and then make the difference to get the pressure drop;

[0017] Step S7: construct a pipeline temperature difference model by combining the difference between the average temperature difference and the temperature information of each pipeline and the resistance value of each pipeline itself, so as to obtain the most unfavorable end of the air-conditioning pipeline.

[0018] The beneficial effects of the present invention are:

[0019] The method for calculating the most disadvantageous end of the air-conditioning pipeline has the advantage of being easy to calculate the most disadvantageous end of the air-conditioning pipeline.

[0020] Based on the above technical solution, the present invention can also be improved as follows.

[0021] Furthermore, the air-conditioning pipeline is a central air-conditioning pipeline, and the central air-conditioning includes a main unit, a refrigerant pipe, a branch pipe, an indoor unit, a water tank, circulating water and a filter, etc., wherein the main unit is composed of a compressor, an evaporator, a refrigerant, etc.

[0022] Furthermore, the central air-conditioning duct is a stainless steel square tube, and the outer side of the central air-conditioning duct is wrapped with a heat insulation layer.

[0023] The beneficial effect of adopting the above further solution is that the heat insulation layer can isolate the heat exchange inside and outside the pipeline to the maximum extent, retaining the cooling or heating effect of the air conditioner.

[0024] Furthermore, the Internet management platform includes an unfavorable pipeline calculation module, a cutoff position selection module and a resistance calculation module.

[0025] The beneficial effect of adopting the above further scheme is that the unfavorable pipeline calculation module is used to calculate the lowest pressure point in the air-conditioning pipeline through the Internet management platform, the cut-off position selection module is used to calculate the branch that needs to be cut off in the air-conditioning pipeline through the Internet management platform, and the resistance calculation module is used to build a pipeline temperature difference model on the Internet management platform in combination with the unfavorable pipeline calculation module. The unfavorable pipeline is a loop with the largest total resistance value in the ventilation and air-conditioning pipeline system.

[0026] Furthermore, the pipeline temperature difference model is fitted by a double Gaussian curve and an exponential function.

[0027] The beneficial effect of adopting the above further scheme is that in the double Gaussian curve, y0 represents the resistance coefficient at 1 to 2 hydraulic radii downstream of the fitting; xc represents the cutoff distance at 1 to 2 hydraulic radii downstream of the fitting; H represents the steepness of the peak; w1 represents a constant that does not change with speed. In the exponential curve, y0 represents the resistance value when the cutoff distance is zero, and A represents the steepness of the curve.

[0028] Furthermore, the control module has a communication function, and determines whether the connection of the pipeline is open through the valve opening and closing signals of the Internet management platform, thereby adjusting the resistance of the branch pipeline.

[0029] Furthermore, through the pipeline temperature difference model, on the basis of determining the most unfavorable end, the pressure required for normal operation of the determined most unfavorable end is sent to the central air-conditioning room, and the output flow and pressure of the refrigeration pump are adjusted to ensure the normal operation of the equipment in the branch pipeline at the most unfavorable end.

[0030] Furthermore, the Internet management platform includes a cloud database, a local database, a comparison module and an analysis module.

[0031] The beneficial effect of adopting the above further scheme is that the cloud database is used to store past pipeline test data, the local database is used to store current integrated test data, the comparison module is used to compare the cloud data with the local data, the comparison module is also used to compare the temperature resistance data of each pipeline horizontally, the analysis module is used to analyze the difference of each pipeline data horizontally and calculate the intermediate value, and the analysis module also always compares and analyzes the cloud data with the local data, calculates the difference value for correction. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 The unfavorable end calculation model of the air conditioning system of the present invention;

[0033] Figure 2 It is a schematic diagram of the system flow of the present invention. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] In the embodiment, Figure 1-2 A method for calculating the most unfavorable end of an air conditioning duct is provided, and the invention comprises the following steps:

[0036] Step S1, installing a temperature control module at the air outlet of each pipeline according to the collected situation;

[0037] The temperature control module includes a temperature sensor and a pipeline valve;

[0038] Step S2: Upload the temperature information collected by the temperature control module to the Internet management platform during calculation;

[0039] Step S3: using the Internet management platform to compare the temperature information of each pipeline;

[0040] Step S4: Analyze the comparison data using the Internet management platform to obtain the average value;

[0041] Step S5, sending the data information to the control module through the Internet management platform, and controlling each pipeline to be cut off through the control module;

[0042] Step S6, using the resistance calculation model to obtain the resistance value of each pipeline, and obtaining the resistance value of each pipeline itself according to the pressure drop method;

[0043] Step S7, constructing a pipeline temperature difference model by combining the difference between the average temperature difference and the temperature information of each pipeline and the resistance value of each pipeline itself, thereby obtaining the most unfavorable end of the air conditioning pipeline;

[0044] The air conditioning pipeline is the central air conditioning pipeline. The central air conditioning includes the main unit, refrigerant pipes, branch pipes, indoor unit, water tank, circulating water and filter, etc. The main unit is composed of compressor, evaporator, refrigerant, etc.

[0045] The central air conditioning pipe is a stainless steel square pipe, and the outside of the central air conditioning pipe is wrapped with a heat insulation layer;

[0046] The thermal insulation layer can isolate the heat exchange inside and outside the pipe to the maximum extent, retaining the cooling or heating effect of the air conditioner;

[0047] The Internet management platform includes an unfavorable pipeline calculation module, a cutoff position selection module, and a resistance calculation module;

[0048] The unfavorable pipeline calculation module is used to calculate the lowest pressure point in the air-conditioning pipeline through the Internet management platform. The cut-off position selection module is used to calculate the branch that needs to be cut off in the air-conditioning pipeline through the Internet management platform. The resistance calculation module is used to build a pipeline temperature difference model on the Internet management platform in combination with the unfavorable pipeline calculation module. The unfavorable pipeline is a loop with the largest total resistance value in the ventilation and air-conditioning pipeline system.

[0049] The pipeline temperature difference model is fitted by double Gaussian curve and exponential function;

[0050] In the double Gaussian curve, y0 represents the resistance coefficient at 1 to 2 hydraulic radii downstream of the fitting; xc represents the cutoff distance at 1 to 2 hydraulic radii downstream of the fitting; H represents the steepness of the peak; w1 represents a constant that does not change with speed; in the exponential curve, y0 represents the resistance value when the cutoff distance is zero, and A represents the steepness of the curve;

[0051] The control module has a communication function, and determines whether the connection of the pipeline is open through the valve opening and closing signals of the Internet management platform, thereby adjusting the resistance of the branch pipeline;

[0052] Through the pipeline temperature difference model, on the basis of determining the most unfavorable end, the pressure required for normal operation of the most unfavorable end is sent to the central air-conditioning room, and the output flow and pressure of the refrigeration pump are adjusted to ensure the normal operation of the equipment in the branch pipeline at the most unfavorable end;

[0053] The Internet management platform includes a cloud database, a local database, a comparison module, and an analysis module;

[0054] The cloud database is used to store past pipeline test data, the local database is used to store current integrated test data, the comparison module is used to compare cloud data with local data, and the comparison module is also used to compare the temperature resistance data of each pipeline horizontally. The analysis module is used to analyze the differences in the data of each pipeline horizontally and calculate the intermediate value. The analysis module also always compares and analyzes the cloud data with the local data, calculates the difference value for correction.

[0055] Working principle:

[0056] Step 1: Install pipeline valves at the air outlet of each pipeline according to the collection situation, and electrically connect the valves to the temperature sensors;

[0057] Step 2: During calculation, the temperature information collected by the temperature sensor is uploaded to the Internet management platform and the local database in the Internet management platform is used. The data information is retrieved through the comparison module for horizontal comparison to obtain the intermediate value. The intermediate value is compared with the local data and the cloud data through the analysis module to obtain the difference value. The control module is then controlled by the Internet management platform to open or close the valve for interception and test the resistance value.

[0058] Step 3: Use the resistance calculation model to obtain the resistance value of each pipeline, and use the pressure drop method to obtain the resistance value of each pipeline itself. Combine the difference between the average temperature difference and the temperature information of each pipeline and the resistance value of each pipeline itself to build a pipeline temperature difference model, so as to obtain the most unfavorable end of the air-conditioning pipeline.

[0059] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0060] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for calculating the most unfavorable end of an air-conditioning pipeline, characterized in that, it includes the following steps: Step S1: Install temperature control modules at the air outlet ends of each pipeline according to the collection situation; wherein the temperature control module includes a temperature sensor and a pipeline valve; Step S2: When calculating, upload the temperature information collected by the temperature control module to the Internet management platform; Step S3: Use the Internet management platform to compare the temperature information of each pipeline; Step S4: Use the Internet management platform to analyze the comparison data and take the average value; Step S5: Send the data information to the control module through the Internet management platform, and control each pipeline to be truncated through the control module; Step S6: Obtain the resistance value of each pipeline using the resistance calculation model, and obtain the resistance value of each pipeline itself according to the pressure drop method; Step S7: Combine the average temperature difference, the difference in the temperature information of each pipeline, and the resistance value of each pipeline itself to construct a pipeline temperature difference model, so as to obtain the most unfavorable end of the air-conditioning pipeline.

2. A method for calculating the most unfavorable end of an air-conditioning pipeline according to claim 1, characterized in that: The air-conditioning pipeline is a central air-conditioning pipeline, and the central air-conditioning includes a host, a refrigerant pipe, a branch pipe, an indoor unit, a water tank, circulating water, a filter, etc., wherein the host is composed of a compressor, an evaporator, a refrigerant, etc.

3. A method for calculating the most unfavorable end of an air-conditioning pipeline according to claim 1, characterized in that: The central air-conditioning pipeline is a stainless steel square pipe, and the outside of the central air-conditioning pipeline is wrapped with a heat insulation layer.

4. A method for calculating the most unfavorable end of an air-conditioning pipeline according to claim 1, characterized in that: The Internet management platform includes an unfavorable pipeline calculation module, a truncation position selection module, and a resistance calculation module.

5. A method for calculating the most unfavorable end of an air-conditioning pipeline according to claim 1, characterized in that: The pipeline temperature difference model is fitted with a double Gaussian curve and an exponential function.

6. A method for calculating the most unfavorable end of an air-conditioning pipeline according to claim 1, characterized in that: The control module has a communication function, and judges whether the connection of the pipeline is opened through the valve opening and closing signals of the Internet management platform, so as to adjust the resistance of the branch pipeline.

7. A method for calculating the most unfavorable end of an air-conditioning pipeline according to claim 1, characterized in that: Through the pipeline temperature difference model, on the basis of determining the most unfavorable end, send the pressure required for the normal operation of the determined most unfavorable end to the central air-conditioning machine room, and adjust the output flow and pressure of the chilled water pump to ensure the normal operation of the equipment on the most unfavorable end branch pipeline.

8. A method for calculating the most unfavorable end of an air-conditioning pipeline according to claim 1, characterized in that: The Internet management platform includes a cloud database, a local database, a comparison module, and an analysis module.

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