Early warning device and early warning method for sudden liquid entrainment of gas pipeline

Abstract

The invention discloses a gas pipeline liquid sudden increase entrainment early warning device which comprises a top pressure guide pipe, a bottom pressure guide pipe, a pressure difference transmitter, a data processing terminal and early warning equipment, the input end of the top pressure guide pipe is communicated with the top end of a gas pipeline, and the input end of the bottom pressure guide pipe is communicated with the bottom end of the gas pipeline; the output end of the top pressure guiding pipe and the output end of the bottom pressure guiding pipe are connected with a pressure difference transmitter. The pressure difference transmitter is used for monitoring parameters of fluid in the top pressure guiding pipe and the bottom pressure guiding pipe. The pressure difference transmitter is connected with the data processing terminal, and the data processing terminal is used for processing fluid parameters monitored by the pressure difference transmitter to obtain a pressure difference value and comparing the pressure difference value with a preset value; the early warning equipment is connected with the data processing terminal; and when the pressure difference value is greater than the preset value, the data processing terminal transmits a signal to the early warning equipment, and the early warning equipment gives an alarm. The problem that an existing early warning device cannot timely and accurately warn the liquid inclusion condition can be solved.

Description

Technical Field

[0001] The present invention relates to the technical field of pipeline defect monitoring simulation, and in particular to an early warning device and an early warning method for sudden increase and entrainment of liquid in a gas pipeline. Background Art

[0002] The production links of natural gas extraction, transportation, purification, and sales all involve the extensive use of gas pipelines, which require gas transportation. Although a small amount of liquid will inevitably be mixed in the gas pipeline, the liquid can generally be discharged through technical means.

[0003] In each production link, there is a risk that a large amount of liquid may be carried into the gas pipeline due to unconventional operations upstream. If the liquid is not removed in advance in time, the liquid will be carried into the production equipment of downstream users, which will seriously affect the normal production of downstream users and even cause safety hazards.

[0004] In order to remove liquid inclusions in advance, a timely and effective early warning device is needed. The existing early warning device cannot timely and accurately warn of the situation of large amounts of liquid inclusions. Summary of the invention

[0005] The purpose of the present invention is to provide an early warning device for sudden increase of liquid entrainment in a gas pipeline, so as to solve the problem that the existing early warning device cannot timely and accurately warn of liquid entrainment.

[0006] The present invention is achieved through the following technical solutions:

[0007] 1. An early warning device for sudden increase and entrainment of liquid in a gas pipeline, comprising: a top pressure-guiding pipe and a bottom pressure-guiding pipe, wherein the input end of the top pressure-guiding pipe is connected to the top end of the gas pipeline, and the input end of the bottom pressure-guiding pipe is connected to the bottom end of the gas pipeline; a differential pressure transmitter, wherein the output end of the top pressure-guiding pipe and the output end of the bottom pressure-guiding pipe are respectively connected to the differential pressure transmitter, and the connection between the bottom pressure-guiding pipe and the differential pressure transmitter is set at a height lower than the setting height of the bottom end of the gas pipeline, and the differential pressure transmitter is used to monitor the parameters of the fluid in the top pressure-guiding pipe and the bottom pressure-guiding pipe; a data processing terminal, wherein the differential pressure transmitter is connected to the data processing terminal, and the data processing terminal is used to process the parameters of the fluid monitored by the differential pressure transmitter, obtain a pressure differential value, and compare the pressure differential value with a preset value; an early warning device, wherein the early warning device is connected to the data processing terminal; when the pressure differential value is greater than the preset value, the data processing terminal transmits a signal to the early warning device, and the early warning device alarms.

[0008] Optionally, the differential pressure transmitter is detachably connected to the top pressure-guiding pipe and the bottom pressure-guiding pipe.

[0009] Optionally, the detachable connection is a threaded connection or a flange connection.

[0010] Optionally, the top pressure-guiding pipe and the bottom pressure-guiding pipe are provided with a top valve and a bottom valve respectively.

[0011] Optionally, the differential pressure transmitter is connected to the data processing terminal via a cable, or the differential pressure transmitter is connected to the data processing terminal via a network signal.

[0012] Optionally, the data processing terminal is a server or a PLC.

[0013] A method for early warning of sudden increase of liquid entrainment in a gas pipeline, using any of the above-mentioned early warning devices for sudden increase of liquid entrainment in a gas pipeline, comprises the following steps:

[0014] Connecting the input end of the top pressure-guiding pipe and the input end of the bottom pressure-guiding pipe to the top and bottom of the gas pipeline respectively;

[0015] Determine a calculation formula for the pressure difference value, and input the calculation formula into the data processing terminal;

[0016] Setting the preset value at the data processing terminal according to the fluid conditions in the gas pipeline;

[0017] When the early warning device sounds an alarm, the top pressure pipe or the bottom pressure pipe is separated from the differential pressure transmitter, and the accumulated liquid and dirt in the separated top pressure pipe or the bottom pressure pipe are flushed to the outside by using the pressure difference between the fluid in the gas pipeline and the outside;

[0018] After flushing is completed, the separated top pressure-guiding pipe or the bottom pressure-guiding pipe is reconnected to the differential pressure transmitter.

[0019] Optionally, under normal operating conditions, the calculation formula is:

[0020] Under normal working conditions, the calculation formula is:

[0021] ΔP=ρ1×H1×g-ρ1×H2×g=0;

[0022] in:

[0023] ΔP is the pressure difference value;

[0024] ρ1 is the density of the fluid in the gas pipeline under normal working conditions;

[0025] H1 is the height of the fluid in the bottom pressure-guiding pipe (11);

[0026] H2 is the height of the fluid in the top pressure-inducing pipe (10);

[0027] G is the acceleration due to gravity;

[0028] Under abnormal working conditions, the calculation formula is:

[0029] ΔP=R×Δρ×ΔH;

[0030] in:

[0031] ΔP is the pressure difference value;

[0032] R is an empirical constant;

[0033] Δρ is the density of the gas-liquid mixed fluid in the gas pipeline under abnormal conditions;

[0034] ΔH is the liquid accumulation height of the fluid in the gas pipeline under normal and abnormal operating conditions.

[0035] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0036] The early warning device for sudden increase and entrainment of liquid in a gas pipeline provided by the present embodiment is provided with a top pressure-guiding pipe and a bottom pressure-guiding pipe, so that the two are respectively connected to the top and bottom ends of the vertically arranged gas pipeline to be tested, and the fluid in the two ends of the gas pipeline is respectively drained into the differential pressure transmitter, and the connection height of the bottom pressure-guiding pipe and the differential pressure transmitter is set lower than the setting height of the bottom end of the gas pipeline, and a pressure difference is formed between the two connecting ends of the differential pressure transmitter by utilizing the difference in fluid density at the top and bottom ends of the gas pipeline and the principle of communicating vessels, and a detection film is provided in the differential pressure transmitter, and the fluid at the two ends of the gas pipeline is respectively drained to the two ends of the detection film, and the film is forced to deform by the pressure difference; on this basis, by providing a data processing terminal, the deformation of the detection film of the differential pressure transmitter generates a corresponding electrical signal, and a pressure difference value is obtained, which is transmitted to the data processing terminal, and the data processing terminal processes the fluid parameters by a specific formula, and provides an accurate alarm by comparing the pressure difference value with a preset value. Node; on this basis, by setting up an early warning device, when the pressure difference value is greater than the preset value, the early warning device will give an alarm in time, so that the problem of a large amount of liquid inclusion exceeding the threshold value can be timely and accurately known, and the maintenance personnel can be timely guided to eliminate the liquid inclusion in the gas pipeline in time; and, by setting the setting height of the connection between the bottom pressure pipe and the pressure differential transmitter lower than the setting height of the bottom end of the gas pipeline, it is convenient for the abnormal working condition gas-liquid mixed fluid to suddenly gather in large quantities at the connection between the bottom pressure pipe and the pressure differential transmitter, the normal working condition fluid gas inside the top pressure pipe can be affected by gravity and discharged into the gas pipeline, ensuring that the top pressure pipe and the bottom pressure pipe measured by the differential pressure transmitter are respectively the normal working condition fluid and the abnormal working condition fluid, avoiding mixing of the two, thereby avoiding measurement errors; through the mutual cooperation of the above-mentioned features, the early warning device for sudden increase of liquid entrainment in the gas pipeline can effectively solve the problem that the existing early warning device cannot timely and accurately warn of liquid inclusion. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of this application, and do not constitute a limitation of the embodiments of the present invention. In the drawings:

[0038] Figure 1 A schematic diagram of an early warning device for sudden increase of liquid entrainment in a gas pipeline provided by an embodiment of the present invention.

[0039] Marks and corresponding parts names in the attached drawings:

[0040] 1-gas transmission pipeline; 10-top pressure pipe; 101-top valve; 11-bottom pressure pipe; 111-bottom valve; 20-differential pressure transmitter; 30-data processing terminal; 40-early warning equipment. DETAILED DESCRIPTION

[0041] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments and drawings. The exemplary embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention.

[0042] First of all, it should be explained that under normal operating conditions, a small amount of liquid is entrained in the gas phase fluid in the gas pipeline 1. Under the action of gravity, the liquid slowly gathers to the bottom of the gas pipeline 1, forming effusion and dirt, causing the fluid density at the bottom of the gas pipeline 1 to be greater than the fluid density at the top, causing the pressure difference value to slowly increase; under abnormal operating conditions, the fluid inside the gas pipeline 1 suddenly entrains a large amount of liquid, and quickly changes from the gas phase to a gas-liquid mixed state, which will cause the fluid density at the bottom of the gas pipeline 1 to suddenly increase sharply, thereby causing the pressure difference value to increase sharply; therefore, the pressure difference value can accurately and effectively characterize the degree of liquid inclusion.

[0043] Please refer to Figure 1The embodiment of the present invention provides an early warning device for sudden increase of liquid entrainment in a gas pipeline, comprising: a top pressure-guiding pipe 10 and a bottom pressure-guiding pipe 11, wherein the input end of the top pressure-guiding pipe 10 is connected to the top of the gas pipeline 1, and the input end of the bottom pressure-guiding pipe 11 is connected to the bottom of the gas pipeline 1; the second includes a differential pressure transmitter 20, wherein the output end of the top pressure-guiding pipe 10 and the output end of the bottom pressure-guiding pipe 11 are respectively connected to the differential pressure transmitter 20, and the connection between the bottom pressure-guiding pipe 11 and the differential pressure transmitter 20 is set at a height lower than the setting height of the bottom end of the gas pipeline 1, and the differential pressure transmitter 20 is used to monitor the parameters of the fluid in the top pressure-conducting pipe 10 and the bottom pressure-conducting pipe 11; the third includes a data processing terminal 30, the differential pressure transmitter 20 is connected to the data processing terminal 30, and the data processing terminal is used to process the parameters of the fluid monitored by the differential pressure transmitter 20, obtain the differential pressure value, and compare the differential pressure value with a preset value; the fourth includes an early warning device 40, and the early warning device 40 is connected to the data processing terminal 30; when the differential pressure value is greater than the preset value, the data processing terminal transmits a signal to the early warning device 40, and the early warning device 40 alarms.

[0044] The early warning device for sudden increase and entrainment of liquid in the gas pipeline provided in the present embodiment is provided with a top pressure-guiding pipe 10 and a bottom pressure-guiding pipe 11, so that the two are respectively connected to the top and bottom ends of the vertically arranged gas pipeline 1 to be tested, and the fluid in the two ends of the gas pipeline 1 is respectively drained into the differential pressure transmitter 20, and the connection height of the bottom pressure-guiding pipe 11 and the differential pressure transmitter 20 is set lower than the setting height of the bottom end of the gas pipeline 1. By utilizing the difference in fluid density at the top and bottom ends of the gas pipeline 1 and the principle of communicating vessels, a pressure difference is formed between the two connecting ends of the differential pressure transmitter 20. A detection film is provided in the differential pressure transmitter 20, and the fluid at the two ends of the gas pipeline 1 is respectively drained to the two ends of the detection film, and the film is forced to deform by the pressure difference. On this basis, by providing a data processing terminal 30, the deformation of the detection film of the differential pressure transmitter 20 generates a corresponding electrical signal, and a pressure difference value is obtained, which is transmitted to the data processing terminal 30. The data processing terminal processes the fluid parameters through a specific formula, and provides an accurate warning by comparing the pressure difference value with a preset value. Alarm node; on this basis, by setting up an early warning device 40, when the pressure difference value is greater than the preset value, the early warning device 40 will give an alarm in time, so that the problem of a large amount of liquid inclusion exceeding the threshold value can be timely and accurately known, and the maintenance personnel can be timely guided to eliminate the liquid inclusion in the gas pipeline 1 in time; and, by setting the connection height of the bottom pressure-conducting pipe 11 and the pressure differential transmitter 20 to be lower than the connection height of the bottom end of the gas pipeline 1, it is convenient for the abnormal working condition gas-liquid mixed fluid to suddenly gather in large quantities at the connection between the bottom pressure-conducting pipe 11 and the pressure differential transmitter 20, the normal working condition fluid gas inside the top pressure-conducting pipe 10 can be affected by the gravity factor and discharged into the gas pipeline 1, ensuring that the internal fluids of the top pressure-conducting pipe 10 and the bottom pressure-conducting pipe 11 measured by the differential pressure transmitter 20 are respectively the normal working condition fluid and the abnormal working condition fluid, avoiding the mixing of the two, thereby avoiding measurement errors; through the mutual cooperation of the above-mentioned features, the early warning device for sudden increase of liquid entrainment in the gas pipeline can effectively solve the problem that the existing early warning device cannot timely and accurately warn of liquid inclusion.

[0045] It should be noted that no isolation fluid needs to be added to the differential pressure transmitter 20 , but the differential pressure (density difference) is combined with the principle of the communicating vessel to force the internal detection film to deform, so as to represent the differential pressure value.

[0046] It should be noted that the data processing terminal 30 may be any related product in the prior art, and only needs to be able to receive data signals and process, calculate and compare the data signals.

[0047] It should be noted that the above-mentioned warning device 40 can adopt any related product in the existing technology, and it only needs to be able to receive signals and perform physical representations based on the signals, such as flashing lights, making sounds, visual displays, digital displays, etc.

[0048] In order for maintenance personnel to promptly handle the accumulated liquid and dirt in the top pressure-guiding pipe 10 or the bottom pressure-guiding pipe 11 , the differential pressure transmitter 20 is detachably connected to the top pressure-guiding pipe 10 and the bottom pressure-guiding pipe 11 .

[0049] Preferably, the detachable connection is a threaded connection or a flange connection.

[0050] In other embodiments, a centrally placed drain valve and drain pipe design may also be used to discharge the accumulated liquid and dirt inside the pipe without disassembly.

[0051] In order to facilitate the sewage discharge operation to be carried out more smoothly, the top pressure-guiding pipe 10 and the bottom pressure-guiding pipe 11 are respectively provided with a top valve 101 and a bottom valve 111.

[0052] By providing the top valve 101 and the bottom valve 111 , sewage discharge, maintenance or debugging are not restricted by whether there is fluid passing through the gas pipeline 1 .

[0053] It should be noted that the differential pressure transmitter 20 is connected to the data processing terminal 30 via a cable, or the differential pressure transmitter 20 is connected to the data processing terminal 30 via a network signal.

[0054] Preferably, the data processing terminal 30 is a server or a PLC.

[0055] The present invention also provides an early warning method for sudden increase of liquid entrainment in a gas pipeline, which is performed using any of the early warning devices for sudden increase of liquid entrainment in a gas pipeline 1, and comprises the following steps:

[0056] S1, connecting the input end of the top pressure-guiding pipe 10 and the input end of the bottom pressure-guiding pipe 11 to the top and bottom ends of the gas pipeline 1 respectively;

[0057] S2, determining a calculation formula for the pressure difference value, and inputting the calculation formula into the data processing terminal 30;

[0058] S3, setting the preset value at the data processing terminal according to the fluid conditions in the gas pipeline 1;

[0059] S4. When the early warning device 40 sounds an alarm, the top pressure pipe 10 or the bottom pressure pipe 11 is separated from the differential pressure transmitter 20, and the accumulated liquid and dirt in the separated top pressure pipe 10 or the bottom pressure pipe 11 are flushed to the outside by using the pressure difference between the fluid in the gas pipeline 1 and the outside;

[0060] S5. After flushing is completed, the separated top pressure-guiding pipe 10 or the bottom pressure-guiding pipe 11 is reconnected to the differential pressure transmitter 20.

[0061] Conventional use of differential pressure transmitters requires filling with isolation fluid. This method uses differential pressure transmitters to measure differential pressure values ​​without filling with isolation fluid. The principle of differential pressure is formed by the different fluid densities in the gas pipeline under normal and abnormal conditions. Based on the measured values ​​of the differential pressure transmitter, the relationship between the fluid density and the height of the accumulated liquid in the pipeline under abnormal conditions is calculated to warn of abnormal conditions.

[0062] ρ1 is the density of the gas phase fluid in the gas pipeline under normal working conditions, ρ2 is the density of the liquid phase fluid in the gas-liquid mixture that may be entrained in the gas pipeline under abnormal working conditions; H1 is the height of the fluid in the bottom pressure pipe 11, and H2 is the height of the fluid in the top pressure pipe 10

[0063] Under normal working conditions, the fluid density in the top and bottom pressure pipes is ρ1, and the fluid height in the top and bottom pressure pipes is 0; under abnormal working conditions, due to the effect of gravity, the height of the gas-liquid mixture increases from 0, and the fluid in the bottom pressure pipe gradually changes from the gas phase fluid in normal working conditions to a gas-liquid mixture. The density of the gas-liquid mixture is Δρ. The density of the gas-liquid mixture is between the meteorological fluid ρ1 in normal working conditions and the full liquid phase fluid ρ2 in abnormal working conditions. The fluid density of the top pressure pipe is ρ1, and the height H1 of the fluid in the bottom pressure pipe 11 begins to increase. When the gas-liquid mixture does not fill the gas transmission pipeline in large quantities, the height H2 of the fluid in the top pressure pipe 10 is 0 under normal conditions.

[0064] In daily management, as gravity acts as an influence, trace amounts of liquid substances carried in the gas pipeline will gradually settle in the bottom pressure pipe, and the values ​​of H1 and H2 will slowly rise under normal working conditions. According to user requirements, a maintenance value a is set. When the measured value ΔΡ≥a, the top and bottom pressure pipes are drained to keep H1 and H2 both 0 when normal.

[0065] The main characteristics of this method are to calculate the empirical constant R according to the medium, pipe diameter, pressure, etc. of the user's gas pipeline, and to use the formula to infer the relationship between the fluid density and the liquid accumulation height in the gas pipeline according to the measured value ΔΡ, and to infer the liquid phase entrainment degree of the fluid in the gas pipeline. According to user needs, the warning value b is determined, and a warning is issued when ΔΡ≥b.

[0066] Under normal working conditions, the calculation formula is:

[0067] ΔP=ρ1×H1×g-ρ1×H2×g=0;

[0068] in:

[0069] ΔP is the pressure difference; ρ1 is the density of the fluid in the gas pipeline 1 under normal working conditions; H1 is the height of the fluid in the bottom pressure pipe 11; H2 is the height of the fluid in the top pressure pipe 10; G is the acceleration of gravity;

[0070] Under abnormal working conditions, the calculation formula is:

[0071] ΔP=R×Δρ×ΔH;

[0072] in:

[0073] ΔP is the pressure difference value; R is an empirical constant; Δρ is the density of the gas-liquid mixed fluid in the gas pipeline 1 under abnormal working conditions; ΔH is the liquid accumulation height of the fluid in the gas pipeline 1 under normal working conditions and abnormal working conditions.

[0074] It should be noted that the preset value can be set according to actual user needs, and different preset values ​​can be set for normal operating conditions and abnormal operating conditions respectively, and displayed separately at the early warning device 40.

[0075] It should be noted that the R value is determined based on the differential pressure gauge specifications, pipe diameter, fluid density, fluid flow, pipe pressure and other parameters, combined with experience and specific experimental requirements.

[0076] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. An early warning device for sudden increase of liquid entrainment in a gas pipeline, characterized in that: include: A top pressure-guiding pipe (10) and a bottom pressure-guiding pipe (11), wherein the input end of the top pressure-guiding pipe (10) is connected to the top end of the gas pipeline, and the input end of the bottom pressure-guiding pipe (11) is connected to the bottom end of the gas pipeline; A differential pressure transmitter (20), the output end of the top pressure-guiding pipe (10) and the output end of the bottom pressure-guiding pipe (11) are respectively connected to the differential pressure transmitter (20), the connection between the bottom pressure-guiding pipe (11) and the differential pressure transmitter (20) is arranged at a height lower than the bottom end of the gas pipeline, and the differential pressure transmitter (20) is used to monitor the parameters of the fluid in the top pressure-guiding pipe (10) and the bottom pressure-guiding pipe (11); a data processing terminal (30), the differential pressure transmitter (20) being connected to the data processing terminal (30), the data processing terminal being used to process the parameters of the fluid monitored by the differential pressure transmitter (20), obtain a differential pressure value, and compare the differential pressure value with a preset value; an early warning device (40), the early warning device (40) being connected to the data processing terminal (30); When the pressure difference value is greater than the preset value, the data processing terminal transmits a signal to the early warning device (40), and the early warning device (40) sounds an alarm.

2. The early warning device for sudden increase of liquid entrainment in a gas pipeline according to claim 1, characterized in that: The differential pressure transmitter (20) is detachably connected to the top pressure-guiding pipe (10) and the bottom pressure-guiding pipe (11).

3. The early warning device for sudden increase of liquid entrainment in a gas pipeline according to claim 2, characterized in that: The detachable connection is a threaded connection or a flange connection.

4. The early warning device for sudden increase of liquid entrainment in a gas pipeline according to claim 1, characterized in that: The top pressure-guiding pipe (10) and the bottom pressure-guiding pipe (11) are respectively provided with a top valve (101) and a bottom valve (111).

5. The early warning device for sudden increase of liquid entrainment in a gas pipeline according to claim 1, characterized in that: The differential pressure transmitter (20) is connected to the data processing terminal (30) via a cable, or the differential pressure transmitter (20) is connected to the data processing terminal (30) via a network signal.

6. The early warning device for sudden increase of liquid entrainment in a gas pipeline according to claim 1, characterized in that: The data processing terminal (30) is a server or a PLC.

7. An early warning method for sudden increase of liquid entrainment in a gas pipeline, characterized in that: The method is carried out using the early warning device for sudden increase of liquid entrainment in a gas pipeline as claimed in any one of claims 1 to 6, comprising the following steps: The input end of the top pressure-guiding pipe (10) and the input end of the bottom pressure-guiding pipe (11) are connected to the top end and the bottom end of the gas transmission pipeline respectively; Determining a calculation formula for the pressure difference value, and inputting the calculation formula into the data processing terminal (30); Setting the preset value at the data processing terminal according to the fluid conditions in the gas pipeline; When the early warning device (40) sounds an alarm, the top pressure-guiding pipe (10) or the bottom pressure-guiding pipe (11) is separated from the differential pressure transmitter (20), and the accumulated liquid and dirt in the separated top pressure-guiding pipe (10) or the bottom pressure-guiding pipe (11) are flushed to the outside by using the pressure difference between the fluid in the gas pipeline and the outside; After flushing is completed, the separated top pressure-guiding pipe (10) or the bottom pressure-guiding pipe (11) is reconnected to the differential pressure transmitter (20).

8. The early warning method for sudden increase of liquid entrainment in a gas pipeline according to claim 7, characterized in that: Under normal working conditions, the calculation formula is: ΔP=ρ1×H1×g-ρ1×H2×g=0; in: ΔP is the pressure difference value; ρ1 is the density of the fluid in the gas pipeline under normal working conditions; H1 is the height of the fluid in the bottom pressure-guiding pipe (11); H2 is the height of the fluid in the top pressure-inducing pipe (10); G is the acceleration due to gravity; Under abnormal working conditions, the calculation formula is: ΔP=R×Δρ×ΔH; in: ΔP is the pressure difference value; R is an empirical constant; Δρ is the density of the gas-liquid mixed fluid in the gas pipeline under abnormal conditions; ΔH is the liquid accumulation height of the fluid in the gas pipeline under normal and abnormal operating conditions.

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