Water Transmission Pipeline Research Articles

Field study on proactive pipe condition assessment using hydroacoustic noise

Condition assessment of water transmission pipelines is of important necessity for prioritizing rehabilitation and preventing catastrophic pipe failure. Hydraulic transient analysis has been investigated for three decades for this purpose and applied to many field studies. However, the significant pipe vibrations caused by the transient generation process and the limited energy and bandwidth of conventional discrete transient pressure waves (e.g., step and pulse waves) limit the accuracy and resolution of the analysis. This paper reports a pilot field study of noninvasive and nondestructive pipe condition assessment using small amplitude and persistent hydroacoustic noise instead of conventional large and discrete hydraulic transient waves. By opening a discharge valve installed at an existing access point, such as an air valve, on the field pipe, hydroacoustic noise was generated at the valve due to the turbulence of the discharge. The hydroacoustic noise was measured by pressure transducers at this access point as well as some other access points along the field pipe. A signal deconvolution process was then applied to the measured hydraulic pressures to transfer them to a compositional impulse response function (IRF), which is composed of IRFs of different pipe sections. A mathematical model was derived to interpret the anomaly-induced spikes on the deconvolution trace. A time-shifting process on the compositional IRFs was proposed to find the locations with pipe condition changes from a specific direction of the pipe. The field study has shown that small-amplitude persistent hydroacoustic noise can replace conventional large hydraulic transient waves for pipe condition assessment.

Signals denoising of leakage pressure in water supply pipelines using an improved wavelet filter algorithm

Abstract Accurate identification of leakage pressure signal is crucial for leakage detection and location of water supply pipelines. However, there is a lot of noise signals in the negative pressure waves generated during leakage accidents, making it difficult to identify leakage signals, and thus seriously affecting the accuracy of leakage detection. Therefore, in this study, we carried out leakage test of water transmission pipeline on our self-built test platform for transient flow with long-distance water transmission pipeline (pipeline length is 160 m, and diameter is 100 mm), and obtained the transient leakage pressure signals under various flow rates (15–55 m3/h). An improved wavelet filtering algorithm was proposed to filter the leakage pressure signal by optimizing the calculation of decomposition layers and the threshold processing strategy, and then compared with the traditional wavelet filtering method. The results show that the improved algorithm can denoise the leakage signals effectively, and the signal-to-noise ratio (SNR), mean square error (MSE) and mean absolute percentage error (MAPE) are all superior to those of the traditional wavelet algorithm. The results can provide support for leakage detection and location of water supply pipeline systems.

Earthquake damage mitigation methods for buried pipelines under compressive loads: A case study of the Thames water pipeline

Promoting tensile failure by providing a proper orientation angle between the pipe axis and the fault line is the main seismic design philosophy for buried steel pipelines. However, most of the severe damage and failures experienced by pipelines are mainly due to negative crossing angle and thus compressive loads acting along the pipeline. This paper investigates different earthquake damage mitigation methods such as Carbon Fiber Reinforced Polymer (CFRP) wrapped pipes, Steel Pipes for Fault Crossing (SPF), and corrugated pipes for buried steel pipelines which are mainly subjected to compressive loads. Therefore, the Thames water transmission pipeline, which is a well-known case study, that suffered major and minor damage due to compressive forces in the 1999 Kocaeli earthquake, is considered to simulate and compare the earthquake damage mitigation capabilities of these countermeasures. The numerical studies are performed by using a three-dimensional nonlinear finite element model. The results show that the use of CFRP composites in buried pipelines, regardless of their thickness, wrapping length, or layer orientation, does not have the expected damage reduction effect, but does increase the effective length between major wrinkles or change the type of pipe failure. On the other hand, SPFs and corrugated pipes are more effective in earthquake damage reduction due to their high axial and rotational capabilities.

The performance of transmission pipelines on February 6th, 2023 Kahramanmaras earthquake: a series of case studies

AbstractThe Mw 7.8 earthquake that struck Kahramanmaras on February 6, 2023, caused significant damage to hydrocarbon and water transmission lines due to permanent ground deformations. Explosions occurred in the Kahramanmaras–Gaziantep Natural Gas transmission pipeline causing disruption of gas in the cities of Gaziantep and Hatay Fault Displacement Hazard. Water transmission pipelines were also damaged due to extreme fault offsets. This paper presents the findings from the earthquake affected zones. Particular attention was given to the performance of the 2600 mm diameter Duzbag–Gaziantep water transmission pipeline due to three reported challenges: (#1) The behavior of the pipe in the Duzbag tunnel, (#2) The pipe bend behavior at the fault crossing, and (#3) The pull-out of the pipe at valve room. Based on field observations, extreme damage forms at pipes were presented. A three-dimensional nonlinear numerical analysis was performed to simulate the observed damage of the reoriented water pipe at the fault crossing for Case #2. The nonlinear finite element model was able to capture the complex nature of the post-yield behavior of steel pipe as well as the damage locations along the pipe and their sequence of occurrences. As a mitigation measure for new pipes, the need for using flexible connections at critical crossings was highlighted. For existing pipes, the importance of developing secondary (by-pass) lines was emphasized.

Rehabilitation challenges for the onshore coal seam gas sector in Australia

The development of conventional oil and gas reserves followed by valorisation of coal seam gas (CSG) reserves in Queensland has seen the installation of over 16,000 wells. These wells are accompanied by thousands of kilometres of gathering lines, compression and water treatment facilities and transmission pipelines. The major rehabilitation challenges for the industry result less from technical challenges but rather from the sheer scale of the task. At present, the CSG industry continues to grow, and few of the CSG wells (other than exploration and appraisal wells) have yet reached the end of their life. The US experience presents a cautionary tale for adequate financial provisioning to mitigate the risks of orphaned wells. Secondly, the rehabilitation of multiple small parcels of land such as drill pads presents logistical challenges. Strategies to aggregate parcels for relinquishment will be required if the industry is to avoid thousands of individual land parcel evaluations at the time of relinquishment. These two rehabilitation challenges will be explored, risks for the industry and community assessed, and a call made for industry and government to work collaboratively to ensure an orderly and responsible rehabilitation program becomes an integral part of ongoing operations.

Simulation of water hammer in long distance water transmission pipeline based on Flowmaster

Long distance water transportation projects are widely used in balancing water resources and other fields. However, the opening and closing of valves often causes significant pressure changes in the pipeline, whether it is positive or negative pressure, which can cause damage to the pipeline, thereby affecting the actual water transportation project. Therefore, based on the method of characteristics, this paper studies the influence of pipeline diameter, length, friction coefficient and valve closing time on the transient flow in the pipeline. The results indicated that the pressure pulsation inside the pipe is mainly concentrated at 0.4hz and its harmonics. In addition, the frequency with high amplitude mainly ranges from 2.5s to 10s, and the closer it is to the valve, the higher the amplitude at the node.

Mechanical Excitation of Large-scale Sprinkler Based on PWM Technology

In order to improve the life of a variable displacement sprinkler irrigation machine, this paper establishes a finite element analysis model to analyze its mechanical excitation law. First of all, in the process of model selection, this paper selects the first span of variable sprinkler as the mechanical excitation analysis model based on the actual operation. Then, in the analysis and setting, the terrain difference is ignored, and the pressure values on the main water transmission pipeline of the first span are equal. Finally, the simulation experiment shows that the amplitude of mechanical excitation is positively correlated with the frequency and amplitude of pressure pulsation, and it is mainly when the valve is closed that caused by the pressure pulsation. It provides research support and direction reference for further weakening mechanical excitation.

Study on the factors influencing air valve protection against water hammer with column separation and rejoinder

Abstract Air valves are used to suppress negative water pressures in water transmission pipelines. They also play a key role during the water filling and drainage stages in pipeline systems. However, systematic guidelines for the selection of air valve parameters are lacking. In practical engineering applications, the selection is mainly based on personal experience. If the selected parameters are not appropriate, negative pressures can occur in a pipeline due to insufficient air inflow or destructive water hammer pressures with column separation and rejoinder, which are caused by rapid air discharge. Given the subjectivity of the selection of air valve parameters in engineering applications, this paper introduces the structure and working principle of two different types of air valves. Combined with engineering examples, the one-dimensional transient flow elastic model and the characteristic method are used to conduct numerical simulations in MATLAB to investigate the influences of the air valve type, the inlet and outlet orifice diameters, and the inflow and outflow discharge coefficients on protection against water hammer with column separation and rejoinder. The inflow and outflow coefficients of the anti-slam air valve have a slight influence on preventing water hammers with column separation and rejoinder. The research results provide a theoretical basis for the rational selection of air valves in practical engineering applications.

Allocation and Utilization of Coal Mine Water for Ecological Protection of Lakes in Semi-Arid Area of China

In the background of water ecological protection, how to utilize the superfluous coal mine water efficiently has become an urgent problem, especially in northwest China, where the fragile ecological environment needs to be protected but lacks water. To solve this problem, this study proposes a new procedure for the allocation and utilization of mine water aimed at the ecological protection of lakes in an arid and semi-arid area. Based on the water balance method, the ecological water supplement of regional lakes is first estimated according to their different protection goals. Next, a trend analysis of water demand and supply is carried out, and the mine water inflow and available quantity are calculated. Meanwhile, the water resource allocation plan is evaluated systematically. In this study, the procedure is applied to the mine water and lakes in Wushen Banner, Inner Mongolia Autonomous Region of China. The results show that: (1) the lakes can be divided into three classifications according to their ecological protection goals, (2) the available amount of mine water will reach 57.17–81.97 million m3 in 2030, and there are about 46.7 million m3 of water that can be adjusted to reach the optimal utilization in 2020, and (3) the mine water after advanced treatment could meet the requirement of lakes. Finally, it outputs the water supplement path and the water quantity, as well as the water transmission pipelines to each lake, which makes up a new water resources allocation plan and a utilization mode of regional mine water. This utilization mode can provide solutions and ideas for improving the ecological environment of regional lakes and promote the construction of regional ecological safety barriers. Moreover, it can be very helpful for optimizing the allocation of regional water resources, and for improving the reasonable utilization of coal mine water.

Thermoeconomic and environmental evaluation of a combined heat, power, and distilled water system of a small residential building with water demand strategy

The most important challenges facing humans are global warming and lack to freshwater. Large-scale desalination has always been of interest, but producing freshwater using heat recovery in small-scale combined heat and power systems has not yet been sufficiently discussed. The small scale desalination is highly required, because it can use small scale recoverable waste heat from the micro/small scale power generators. Decentralized small scale desalination systems are more feasible and reliable than centralized big desalination systems for the time of crises such earthquake, war and terrorist attacks, and water loss reduction due to water transmission pipelines. In this research, a cycle is designed for simultaneous production of power, heat and freshwater in small scale for residential buildings. The power generator is a micro gas turbine by Capstone Company. The cycle feasibility is studied by energy, exergy, economic, and environmental criteria, and the design of the desalination is presented in details. The sizing of the system’s components is done according to the following water demand strategy. Evaluations show that the proposed system is feasible from thermodynamics, economic, and environmental viewpoints. The simulation is done by code generation in MATLAB software. The footprint area to install the small scale multi-stage flash desalination is 0.25 m2. The net present value is 25 million United States dollar with payback period of less than 2 years. It also reduces carbon dioxide about 39 tons/year.

Modeling spherical turbines for in-pipe energy conversion

In-pipe hydrokinetic systems employing spherical turbines that operate in confined flows with high blockage ratio are a relatively new technology. The number of modeling and computational studies analyzing the performance of spherical turbines operating in confined area is quite limited. The main objective of this study is to model a novel in-pipe cross-flow turbine and perform numerical analyses. Accordingly, a five bladed spherical rotor was designed and numerical simulations were conducted for various inlet velocities (0.8–6.5 m/s), tip speed ratios (0.6–5.2) and blockage conditions (0.59–0.83). The relationships between geometric, dynamic parameters and power performance were discussed. The findings showed that increasing blockage ratio significantly improved the power performance by shifting the CP-λ curve to the right-upward direction. The output power was maximized by a factor of 2.5 where the pipe diameter is reduced from 1.3 to 1.1 times the turbine diameter. A linearly increasing relationship was achieved between power coefficient and blockage where the angle was proportional with λ. Optimum λ was obtained around 4.2 at high blockage where it was mostly between 1.5 and 2 in free flow turbines. This research is expected to contribute to spherical turbine studies for optimal power generation and energy efficiency in water transmission pipelines.

상수도관로 비파괴 진단을 위한 정책제안

Nondestructive diagnostic technology can be used to check for abnormalities such as metal loss, deformation, and cracks in water pipelines. However, new standards and guidelines for water pipeline maintenance must be revised or established in order to apply new technologies such as nondestructive diagnosis to the field. Herein, policies and guidelines are proposed for the diagnosis of water pipelines using nondestructive technology. Amendments are proposed to allow accurate and reliable nondestructive diagnostic technology to be applied to pipeline maintenance by reviewing the diagnostic standards and laws for water pipelines. The design standards for water conveyance, water transmission, and water distribution pipelines have been revised in order to use advanced technologies such as nondestructive technology to identify abnormalities while minimizing the impact on facilities when inspecting and diagnosing water pipelines. In addition, a revision of the detailed guidelines of the Ministry of Land, Infrastructure, and Transport according to the KS and ASTM standard is required to allow for the use of nondestructive equipment when inspecting welds. Nondestructive diagnostic guidelines that summarize the characteristics and performance of nondestructive diagnostic equipment, diagnostic procedures, and verification processes are also proposed to help managers understand the technology and easily apply it in the field when diagnosing water pipelines.

Seismic Resilience Assessment of Tehran's Southern Water Transmission Pipeline Using GIS-based Analyses

Seismic Resilience Assessment of Tehran's Southern Water Transmission Pipeline Using GIS-based Analyses

Seismic Response of a Water Transmission Pipeline Across a Fault Zone Adopting a Large-Scale Vibration Table Test

The seismic response is generally amplified significantly near the fault zone due to the influence of discontinuous interfaces and weak-broken geotechnical structures, which imposes a severe geologic hazard risk on the engineering crossing the fault. The Hanjiang to Weihe River Project (phase II) crosses many high seismic intensity regions and intersects with eight large-scale regional active faults. Seismic fortification of the pipelines across the fault zone is significant for the design and construction of the project. A large-scale vibration table test was adopted to investigate the seismic response and fault influences. The responses of accelerations, dynamic stresses, strains, and water pressures were obtained. The results show that the dynamic responses were amplified significantly by the fault zone and the hanging wall. The influence range of fault on acceleration response is approximately four times the fault width. The acceleration amplification ratio in the fault zone generally exceeds 1.35, even reaching 1.8, and the hanging wall amplification ratio is approximately 1.2. The dynamic soil pressure primarily depends on the acceleration distribution and is apparently influenced by pipeline location and model inhomogeneity. The pipeline is bent slightly along the axial direction, accompanied by expansion and shrinkage in the radial direction. The maximum tensile and compressive strains appear at the lower and upper pipeline boundaries near the middle section, respectively. Massive y-direction cracks developed in the soil, accompanied by slight seismic subsidence. The research findings could provide reasonable parameters for the seismic design and construction of the project.

Numerical modeling of water hammer in long water transmission pipeline

In the present study, a water transmission pipeline under steady conditions is modeled followed by examining the transient flow created by the failure of pumps in the pipeline. This pipeline is 31 km from the water transmission pipeline of Kerman, Iran. The software analysis results were compared with those of a numerical model for a laboratory test to validate transient flow modeling. While transient flows are created by pump failure, various areas of the water transmission pipelines will be affected by the transient waves produced. Long water transmission pipelines, usually large in diameter and flow rate, will pose problems in the negative pressure phase. The negative pressure causes threatening problems like water column separation and cavitation. The results indicated that using equipment like air valves when the pumps fail alone does not have the appropriate efficiency in eliminating the hazards in the water transmission pipelines. More examination showed that installing equipment like water flow feed and hydropneumatic tanks along the pipeline length in the right places prevents the negative pressure created and the pipeline risk significantly reduces.

Feasibility of hydropower generation on existing Legedadi water supply scheme, Addis Ababa-Ethiopia

Hydropower can be harnessed by installing in-pipe turbines with the reduced cost compared with hydropower dam construction. Legedadi Water Supply Scheme is found in Addis Ababa and is fed by gravity. This research assesses the hydropower potential of the existing large water transmission pipelines in line with their financial viability. The research required the collection of data from pipe flow (for 29 years from the system record) and pipe layout drawings believed to be useful for estimating the power. The available pipe layout drawing was processed to prepare a profile view with the help of AutoCAD CIVIL 3D. From the profile view, the gross heads and length of the pipelines were obtained. The exploitable power and financial viability of the projects were estimated by RET Screen software. The raw water main (DN1200) was discovered to have a head of 12.46 m and to convey up to 1.47 m3/s at 90% exceedance over a length of 550 m. The two treated water mains have a head of 19.15 m with a flow of 1.14 m3/s at 90 % exceedance via DN1200 and 0.29 m3/s at 90% exceedance via DN900 over a length of 18.4 km. The most suitable sites for the installation of turbines were at the inlet of the treatment plant and the Kotebe Terminal Reservoir. The Toshiba Hydro-eKIDS turbine was selected since it might work efficiently with large flow variation.The annual energy output from the raw water main to be obtained was 1,208 Mwh,with an estimated cost of $461,000 and an annual savings or revenue of $75,946. For the treated water mains, 1,193 Mwh (DN1200) and 344 Mwh (DN900) could be extracted with an estimated cost of 414,500$ (DN1200) and 135,900$ (DN900). The annual revenue for treated water mains is 75,068$ (DN1200) and that for DN900 is 18,842$.

Zhoushan City Mainland Water Diversion Phase III Project Key Technologies of Cross-sea Pipeline Laying Construction

This paper introduces the cross-sea water transmission pipeline project from Zhenhai to Mamu section of Zhoushan Continental Water Diversion Project Phase III, and summarizes the towing method of the nearshore section of the pipeline laying, the S-Lay, Post-trenching technology and concrete chain row installation construction techniques. Through the summary of the paper, it is expected to provide help for the construction of the sea bottom pipeline for island water supply in the future.

Feasibility of Mini Hydropower in Water Transmission Pipelines

Feasibility of Mini Hydropower in Water Transmission Pipelines

Valve Location Method for Evaluating Drain Efficiency in Water Transmission Pipelines

Water transmission pipelines, which transport bulk water into storage facilities, usually have a tree-type configuration with large dimensions; thus, the breakage of a pipeline may cause a catastrophic service interruption to customers. Although drain efficiency is closely related to the number of washout and control valves and their locations, there is no useful guideline. This paper proposes a valve locating method by introducing numerical analyses to enumerate drainage time and zone. A time integration method, combined with the Newton–Raphson algorithm, is suggested to resolve drainage time, while considering the friction loss in gravitational flow. A drain direction matrix, which shows drain direction and coverage, is derived using a network searching algorithm. Furthermore, a feasible practical approach is presented by introducing a critical horizontal slope, a major washout valve, drainage indices, and control valve embedment. The developed method is first applied to simple pipes to validate the drainage time module. Subsequently, the model is expanded to the CY transmission line, which is one of the BR water supply systems in South Korea currently in operation. The results reveal that three drain valve locations have been neglected, and the addition of control valves guarantees consistent drain time below the operational criteria.

Recovering energy by hydro-turbines application in water transmission pipelines: A case study west of Saudi Arabia

Pressurized water transmission lines reserve amounts of energy that are dissipated by pressure control devices. The dissipated energy may be recovered by installing hydro-turbines at high pressure points and benefit from power production and decreasing CO2 emissions. In this work, an existing transmission water pipe was simulated under several velocity scenarios, and results indicated that an extensive amount of energy can be recovered by installing Pelton turbines. The approach began by identifying the location of the residual pressure in the system and quantifying the amount of power to be harvested. Afterwards, the pipeline was redesigned by changing the allowed velocity from 1 to 2.5 m/s consecutively. Moreover, the best fitting turbine was selected at each of the residual pressure locations and outputted the potential amount of power to be produced. Finally, a financial and environmental evaluation of the presented solution was conducted. Based on this methodology, the total system cost was reduced by 2.74% because of adopting the maximum allowable velocity of 2 m/s. System optimization allowed for the installation of hydro-power plants with total capacity of 5,751 kW and energy payback period of 9.46 years. Moreover, a reduction in carbon footprint was estimated by 35,295t of CO2 per year.