bluuebunny/crossref_metadata_2025 huggingface dataset:
1825-Lb-Pressure Topping Unit With Special Reference to Forced-Circulation Boiler
Authors: Clark F. S. , Rosencrants F. H. , Armacost W. H.
Published: December 2022

Because of current War Department regulations, the name and location of the power company whose additional facilities are discussed in this paper cannot be divulged at the present time. Originally the power station, established in 1923, incorporated turbine-generator capacity in two units of 75,000 kw, supplied by 375-psi, 750 F steam at the throttles by five boilers having a continuous steam-generating capacity of about 1,000,000 lb per hr. Early in 1940, economic and engineering studies were undertaken by Stone & Webster Engineering Corporation, leading to improvements in the economy of the station and additional generating capacity. The result is the installation of a 25,000-kw superposed turbine generator with one boiler having a continuous steam-generating capacity of 650,000 lb per hr at 1825 psi and 960 F at the superheater outlet. This forced-circulation boiler is the first of its type ever installed in this country and is 85 per cent greater in capacity than any of similar type installed in European plants. The authors discuss comprehensively the details of this boiler and its operation.
Experimental Investigation of Tube Expanding
Authors: Grimison E. D. , Lee G. H.
Published: December 2022

This paper gives results of an experimental investigation to determine (a) the fundamentals involved in tube expanding; (b) the various practical methods of measuring the degree of expansion; (c) the optimum degree of expanding; and (d) the ultimate strengths of expanded joints under various conditions of service. Characteristic relationships of seat pressure on tube to degree of expanding are given, which clearly show the optimum degrees of expanding. An explanation for the existence of the optimum is developed. Determinations of structural strengths of joints under instantaneous loading to failure are reported, as well as the results of repeated smaller loadings through 1000 cycles. The joint was not injured by these repeated applications of loads. The investigation has derived information which has led to a more positive procedure for rolling-in tubes.
Overfire Air Jets
Authors: Engdahl R. B. , Holton W. C.
Published: December 2022

For many years overfire air jets have demonstrated their effectiveness for smoke abatement as well as for increasing the ratings of existing furnaces. Except for the chain-grate stoker on which fan-driven overfire air jets have become standard equipment, jets in this country have been actuated mainly by high-velocity steam from nozzles. Their wide use has been due largely to a minimum of engineering and auxiliaries, and in spite of demonstrably poor efficiency and high steam consumption. Because of uncertainty as to the effects of variables involved in a steam jet, there has been reason to believe that among the available types, there are some which might compare favorably in economy with fan-driven jets. To determine the relative performances of steam jets and fan-driven overfire jets, the authors undertook a laboratory study of the problem at Battelle for Bituminous Coal Research, Inc. The results are given in this paper, as well as a comparison with the meager information which had been made available from earlier investigations.
Lignite—Influence of Storage Conditions Upon Size Degradation, Size Stability, and Friability
Authors: Eckhardt C. J. , Yates C. W.
Published: December 2022

This paper is presented for the purpose of focusing attention on the little known possibilities of lignite as a direct source of potential energy for power-generating and industrial purposes, for the manufacture of gaseous fuels, and for the manufacture of liquid fuels. More than 18 per cent of the nation’s reserve of mineral fuels consists of lignite, but only an insignificant fraction of this low-rank solid fuel is being utilized. Test data are presented to dispel misconceptions concerning the characteristics of lignite which today stand in the way of its more extended use. The most serious of these relates to its tendency to undergo size-reduction processes while in storage and being handled. Nevertheless, it has been demonstrated that it is possible to store this fuel with complete satisfaction, the conclusions reached from the tests described giving factual support to the possibilities in this direction. Size stability, or measure of the ability of lignite to withstand a reduction in size of particles when being handled, and friability tests are also reported.
Investigation of Large Diesel-Engine Wristpins, Pistons, and Crankcase Explosions
Authors: Faast F. E.
Published: December 2022

The causes of crankcase explosions in large Diesel engines have been somewhat obscure, although it has been suspected that wristpins might be the principal source. This paper contains the results of a research undertaken to solve certain wristpin and piston difficulties in large marine Diesels which had experienced disastrous explosions of this nature. Experiments were carried out on slotted-end wristpins having 0.001 in. clearance in the piston bosses, for the purpose of studying the effects of different equivalent amounts of wristpin and boss interference on (a) piston deflections; (b) strained shape of the boss; (c) holding power in boss. The possibility is demonstrated that large wristpin deflections in fixed-end wristpins can cause excessive bearing pressures and temperatures, rupture of oil film, large skirt deflections, all of which constitute explosion hazards and may cause rupture of the piston skirt. It is suggested that these and other difficulties noted in the paper could be eliminated by the use of full-floating wristpins with suitable piston skirts.
A Novel Iterative Field Search Approach to Minimum Zone Circle for Roundness Error Estimation
Authors: Singh Deep , Arunachalam N.
Published: December 2022

Roundness is one of the common attributes in the manufacturing industry. Roundness is the most prominent of the extant fundamental forms, as the majority of the fabricated components are round or cylindrical. The examination of roundness error associated with such features is critical since inadequate evaluation might result in the rejection of excellent parts. The performance of any equipment depends on the mating parts. Out-of-roundness components cause the inefficiency of such equipment’s system performance. As a result, roundness error assessment is critical for macro-sized specimens as well as for micro- and nano-sized components. The present article proposes a novel approach to Minimum Zone Circle (MZC) to evaluate the roundness error. An iterative field search methodology is used in the suggested approach. The proposed methodology evaluates the roundness error based on the generated discretized points within the search space and continues the same by decreasing the search space with an increase in the number of iterations to attain the Minimum Zone Error (MZE). The proposed algorithm has been tested with ten CMM (coordinate measuring machine) datasets and ten form datasets available in the literature studies and found to be excellent in comparison to the existing techniques. Further, the proposed methodology was also implemented to estimate the MZE of centerless ground specimens at multiple cross sections, and the roundness error obtained was lesser as compared to the LSC, MCC, and MIC. The number of generated discretized points is flexible and can be varied to reduce the number of iterations and computations. The recommended method is quite effective in assessing the roundness error when compared to the existing techniques. It also works well on data that was both evenly and unevenly spaced. The results suggest that altering the search field area for higher computing efficiency is straightforward, resilient, and versatile.
Additive Manufacturing of a High Temperature, Ni-Based Superalloy Compact Heat Exchanger: A Study on the Role of Select Key Printing Parameters
Authors: Battaglia Fabio , Zhang Xiang , Arie Martinus A. , Shooshtari Amir , Sarmiento Andres Paul , Ohadi Michael
Published: December 2022

Compared to state-of-the-art heat exchangers, manifold-microchannel heat exchangers have shown superior heat removal density (kW/kg) at moderate pressure drops. However, manifold-microchannel heat exchangers made of Ni-based superalloys or other tough-to-machine materials can be a challenge to fabricate using conventional fabrication methods. This is mainly because of the inherently complex manifold microchannel geometry, as well as the required small feature sizes (e.g., fin thickness) that should be comparable, or smaller than state-of-the-art high-performance metallic-based heat exchangers (∼150 μm or smaller). In this study, a direct metal laser sintering (DMLS) additive manufacturing technique was used to fabricate the compact high-temperature manifold-microchannel heat exchanger reported here. The additively manufactured manifold-microchannel heat exchanger was fabricated as a single object, which significantly simplifies the fabrication process. In this work, three different additive manufacturing machines were used to study the effect of laser power, powder size, and layer thickness on the fin and channel sizes of the fabricated microchannel heat exchangers. To evaluate the minimum wall thickness for holding the required design pressures, pressure containment tests were performed. As a result, a wall thickness of 0.3 mm was shown to withstand 340 kPa and be leakage-free. A detailed analysis of different printing orientations and their effect on the manifold-microchannel heat exchanger's design was also performed. Finally, a 76 × 76 × 76 mm3 manifold microchannel heat exchanger was successfully fabricated with a fin thickness of 0.13 mm out of maraging steel. A second unit with dimensions of 94 × 87.6 × 94.4 mm3 was successfully fabricated with a fin thickness of 0.22 mm out of Inconel 718. Details of the fabrication process and key take-away results are discussed in this paper.
Research on the Buckling Load of Clamped Spherical Caps Under External Pressure: Analyzed by the Fourier Series Model With Initial Geometric Imperfections
Authors: Zheng Sanlong , Zhang Yiqi , Xu Jiawei , Chen Bingbing , Wang Pengfei , Liu Yang
Published: December 2022

The knockdown factor (KDF), which characterizes the difference between the actual buckling pressure and the classical theoretical pressure of clamped spherical caps under external pressure, is highly discrete. The mechanism that causes this discreteness is still not understood and has not been reproduced in numerical simulation. By scanning six clamped spherical caps, the geometric characteristics of the shells were analyzed, and a geometric model was established based on the Fourier series. The geometric model was simulated by the geometric and material double nonlinear buckling analysis method. The results were compared with the experimental data from this study and other references. 720 sets of clamped spherical caps under external pressure were simulated using the proposed Fourier series model and simulation method. The influence of the yield strength, geometrical parameter λ, dimensionless parameters radius-thickness ratio R/t, and the imperfection-thickness ratio e/t on KDF were studied, and the highly discrete characteristics of KDF were reproduced. The results showed that the proposed method has a better predictive effect on KDF, which is significantly improved over the “Eigemode imperfections” method. KDF is not only related to λ and e/t, but is also affected by the yield strength and R/t. The lower envelopes of KDF were obtained when e/t was less than 1.0 and 2.0. The NASA SP-8032 curve corresponds to the lower envelope of KDF when e/t is less than 8.0, and the curve is below the lower envelope of KDF when e/t is less than 1.0 and 2.0. As stipulated in the pressure vessel standard, the KDF obtained by NASA SP-8032 will be conservative for design conditions with e/t less than 1.0 or 2.0, and appropriate adjustment should be considered.
Experimental Research of the Entire Wave System Inside a Wave Rotor Refrigerator and the Impact of Pressure Ratios on the Equipment Performance
Authors: Zhao Yiming , Ji Yawen , Hu Dapeng , Wang Jingxian
Published: December 2022

The wave rotor refrigerator (WRR) is an efficient refrigeration technology. For the purpose of investigating the gas wave characteristics inside the rotor channels of WRR device, the performance and pressure monitoring experiments were conducted at various pressure ratios in this study, and the main findings are as follows: the computation method can produce an accurate design of pressure ports though the post-wave gas pressure of numerical computation has a certain difference with the experiment because of the actual gap leakage and friction loss. The deviation of working pressure ratio from the design values results in the reversed/reflected compression waves or worsens gas leakage, which lowers the equipment performance. When the expansion ratio α is constant, the efficiency reduction ratio does not exceed 11.9% as the relative variation rate of the compression ratio is less than 150%; When the compression ratio β is constant, the efficiency is relatively lowered by a proportion less than 16.4% as the relative increasing ratio of α is less than 63%. This study improves the mechanism of WRR and demonstrates the strong ability of WRR to resist fluctuations in working conditions.
Model Reference Control-Based Steering Feel Improvement for Electric Power-Assisted Steering System
Authors: Li Yijun , Shim Taehyun , Wang Dexin , Offerle Timothy
Published: December 2022

Drivers are sensitive to steering feel of a vehicle and significant tuning efforts are placed to set the desired steering feel. This paper discusses a closed-loop torque overlay control system to improve the steering feel of an electric power-assisted steering (EPAS) system. This system has reference model, rack force estimator, and tracking controller. A target steering feel is generated from a reference model in which it uses an estimate of rack force determined from a Kalman filter-based rack force estimator to reflect the actual vehicle operating conditions. A sliding mode controller is designed for tracking the target steering feel. The performance of the proposed control system is evaluated through simulation and a hardware-in-the-loop test. The simulation and experimental results show that the EPAS system with the proposed control method can successfully improve the steering feel under various operation conditions.
Single Phase CFD Method Validation Based on PIV Experimental Data
Authors: Zhao Jiayin , Ren Bing , Gan Fujun , Yang Ping , Qiu Yifan
Published: December 2022

The present paper aims to verify the existing CFD method and determine the optimal combination of the models and parameters. Single phase 5 × 5 bundle flow field is analyzed and validated based on the Particle image velocimetry (PIV) experimental data. By comparing the fluid velocity distributions at different sections and positions downstream of the grid, the effects of different grid basic sizes, mesh refinement in grid area and turbulence model on the calculation results are investigated. The results show that, when the mesh is refined to a certain extent, the change of calculation results tends to be stable, and the basic size of 0.4mm is used for subsequent calculation. Mesh refinement in grid area only has a certain influence on the flow calculation at zone near grid (1 Dh). In the 4 ∼ 20 Dh downstream of the grid, the simulated values under different turbulence models are different, the simulated values for standard quadratic k-ε (SKE) and realizable k-ε (RKE) are larger, while the improved quadratic k-ε is better for simulating the velocity analysis. All three turbulence models overestimate velocity at other zones. The results provide references to the establishment of a systematic and reliable high-precision numerical method for simulating the flow and heat transfer performance in the fuel rod bundle.
Numerical Research on Coupling Heat Transfer Characteristics of PRHR HX Primary and Secondary Sides
Authors: Liu Jingwen , Zhang Yuhao , Fu Jingpin , Lu Daogang
Published: December 2022

Passive residual heat removal heat exchanger (PRHR HX) in AP1000 is important for the safety of reactor and core as the main heat transfer device for cooling the primary circuit coolant during the residual heat removal. This C-type heat exchanger is vital in ensuring the safety of the reactor in accident conditions. Theoretical calculation methods and research for the coupling heat transfer of the primary and secondary sides of a new C-type heat exchanger with double natural circulation are limited. In this paper, the heat transfer characteristics of the passive residual heat removal tubes are studied from three aspects: theoretical calculation, experiment and numerical simulation. Theoretical calculations used multiple heat transfer calculation models to obtain the heat transfer characteristics such as temperature distribution in the tube. Scaling experiments with primary and secondary side coupling of PRHR HX were carried out and experimental data was obtained. Numerical model of C-tubes was simplified and established based on the experimental device, and coupling heat transfer process inside and outside the C-tube was simulated by FLUENT. The comparisons mentioned above present the coupling heat transfer characteristics in double natural circulation on the primary and secondary sides of PRHR HX. Its outlet temperature decreases obviously compared with inlet temperature, with an average heat transfer coefficient of 1000–2000 W/m2·K. It indicates that the new C-type heat exchanger has a strong ability for heat transfer and most of the coolant heat can be taken away during the operation. This also further validates the accuracy of theoretical calculation.
Analysis of Flow Noise and Vibration Performance for Heat Supply Network Bleed Valve
Authors: Lu Jibing , Shen Mengling , Xing Cangmei , Wen Caizhang , Wu Zeyu
Published: December 2022

The heat supply network bleed valve is located in the steam pipe of the steam turbine heater. When conveying the steam medium of high temperature and high pressure, it impacts the valve disc and pipe wall, resulting in flow-induced vibration and noise of the pipe, resulting in excessive pipeline vibration, which is not conducive to the normal operation of the heat supply network and stable steam supply. In this paper, by using large eddy simulation turbulence theory to study bleed valve disc under different rotation angle operating characteristics, pipe flow field regularity of distribution, and the pressure pulsation of measuring points, the Q criterion is applied to analyze the locomotion mechanism of vortex structure in the downstream flow field of the valve disc, the use of common noise prediction method to calculate the noise of the heat supply network structure features, analysis of the inherent law of flow-induced vibration. It is found that with the increase of the rotation angle of the valve disc, there is an obvious negative pressure center area at the back of the valve disc, and the vortex is formed under the action of the adverse pressure gradient. The decrease in vortex size makes the flow efficiency at the back of the valve increase significantly. Large eddy simulation results show that the fluid generates a double vortex structure similar to the dean vortex behind the valve, and is eventually broken and separated due to the dissipation of viscous turbulent kinetic energy. The smaller the rotation angle is, the more seriously the dissipation vortex blocks the flow area near the pipe wall. The noise characteristics of the flow field in the heat supply network present a dipole state and the overall broadband characteristics. The energy of the flow field is concentrated in the low and middle frequency, and there is a peak of noise SPL. Simulation results showed that when the valve disc rotation angle is less than 30°, the vortex structure will seriously block the pipeline flow area, accounting for more than 90%, and the pipeline flow efficiency will decrease significantly with strong pulsation and noise. The fundamental frequency of the noise in the heat supply network shows a frequency doubling relationship with the natural frequency of the structure, and the rotation angle of the valve disc is negative correlation significantly with the magnitude and position of the fundamental frequency of the noise. Both of them can induce the flow-induced vibration and noise of the heat supply network, which complies with the field measurement data.
Numerical Simulations of CHF in a Single Rod Channel Using OpenFOAM
Authors: Zheng Pengde , Liu Chang , Li Zhenzhong , Chen Deqi , Wu Haochuang
Published: December 2022

This study aims to develop an experimental verification calculation model based on the open source CFD platform OpenFOAM to simulate boiling flow in single rod channel. Two-fluid model coupled with improved RPI wall boiling model (i.e. CHF model) was employed to investigate the departure from nuclear boiling (DNB) phenomena in a single rod under extremely high heat flux. The corrected wall heat flux partitioning model was implemented in the OpenFOAM to simulate two-phase boiling. A good agreement between the predicted CHF and experimental results was observed. On this basis, the effects of coolant mass flow and inlet subcooling on CHF were numerically studied. The results shown that two-fluid model coupled with CHF model was qualified to predict CHF accurately. This work can be referred when one predicts CHF in complicated geometry by CFD methodology.
Experimental Study on Condensation Heat Transfer Characteristics of Vertical Surface Chromium-Plated Tube With Condensate Gas
Authors: Hou Xiaofan , Yao Shiwei , Jiu Jinrong , Wang Qianglong , Chen Hanying
Published: December 2022

An experimental research on the condensation heat transfer characteristic of surface chromium-plated tube was put forwards with non condensation gas. The experimental result suggests that the factors of pressure, air mass fraction and wall subcooling affect the condensation heat transfer process of surface chromium-plated tube, which is similar to that of stainless steel tube. In addition, by comparing with the stainless steel tube, the chromium-plated tube condensation heat transfer capacity changes more obviously with the variation of air mass fraction. That is to say, under the low air mass fraction condition, due to the existence of non condensation gas layer, the difference between those two tube-types is little; but under the high air mass fraction condition, the condensation heat transfer capacity of surface chromium-plated tube is higher than stainless steel tubes lightly. At last, by fitting the experimental data, the empirical formula of condensation heat transfer of surface chrome-plated tube under the condition of non condensing gas is obtained. The deviation is less than 20%.
Numerical Simulation Analysis of the Air Temperature Measurement Scheme for Big Space in Containment
Authors: Fan Tiexin , Zeng Xianbin , Niu Qi , Tu Bin , Huang Dongshan , Liu Zhengjie
Published: December 2022

During the design phase of a nuclear power plant (NPP), the average temperature of air in the containment was used as an input parameter for the analysis of the Loss of Coolant Accident (LOCA) and Main Steam Line Break (MSLB). Considering the complicated air temperature field distribution in the containment, it is uncertain that if the measurement results of these thermometers in the big space above the main operation platform (MOP) of the Reactor Building (RB) are representative in normal operation. Here we show a method of analysis: based on the Computational Fluid Dynamics (CFD) software, the Three-Dimensional model of the space above the MOP in the RB was established using Computer Aided Design (CAD) software Solidworks, according to the structures, heat dissipation of components, and ventilation in it. The model was meshed using the ANSYS ICEM meshing technology. The numerical simulations and finite element analysis were finally finished using ANSYS CFX software. Then the characteristics of air temperature field and velocity field were obtained. Our results demonstrate the feasibility of the air temperature measurement scheme in the space of this analog, and provide theoretical basis for the correction of the average measured value by comparing the simulation results of the temperature field.
Numerical Investigation Into the Water-LBE Interaction by a 3D CFD Code
Authors: Chen Meilan , Du Haoming , Li Changying
Published: December 2022

During the potential Steam Generator Tube Rupture (SGTR) accident in lead-bismuth eutectic alloy (LBE) reactors, certain amounts of high pressure water are injected into the primary loop which is with high temperature. Water and liquid metal reacts strongly when they come into react and the flash evaporation of water may occur, which often induced high pressures. In the present study, a 3D CFD code is applied to investigate the key phenomena of SGTR and the flash evaporation in LBE-water interaction. The experiment of LIFUS test is firstly simulated and validated against the code. The VOF model is applied to simulate the multiphase flow, while the flash process is simulated with an evaporation-condensation model. The calculated results of pressure and temperature agreed in a good trend with the experimental data. Then more investigation is performed to study the consequences of the interaction with variation of mass flow rates, mass of injected water and temperatures of LBE and water. The investigation shows that the mass of water injected and the temperature difference between LBE and water has an effect on the peak pressure while the flow rate has an effect on the pressure rise rate during the rapid pressure rise phase in LBE-water interactions.
A Case Study Applying Gouge Classification to Mechanical Damage Defects
Authors: Romney Matt , Burden Dane
Published: December 2022

Mechanical damage is a leading cause of serious pipeline incidents worldwide. Anomalies caused by it, including those associated with third-party damage, are challenging to detect, classify and size. In particular, in-line inspection (ILI) systems have had difficulty inspecting dent regions for coincidental gouging and distinguishing gouging from corrosion. This is a problem as gouging, which occurs when the pipeline is damaged by mechanical or forceful removal of metal from a local area on the pipe surface, tends to be more susceptible to cracking.

Key to achieving proper mechanical damage assessment is a comprehensive inspection of the pipeline using multiple technologies plus the implementation of advanced data analysis algorithms, including machine learning techniques.

Using the T.D. Williamson (TDW) Multiple Dataset (MDS) platform to provide comprehensive pipeline assessment along with the recent development of advanced machine learning models has resulted in the first gouge classifier backed by an industry compliant performance specification.

Through this innovative development, the pipeline industry has access to accurate classification of dents with coincident gouging. Once accurately classified, validation of depth sizing performance for metal loss, both gouges and non-gouges, located coincident with a dent is achieved.

This paper will outline the history of the gouge classifier development, recent improvements and enhancements made to the classifier, and an overview of the classifier performance when applied to a recent ILI project. Classifier model performance metrics, specifically precision and recall, will be reviewed. Post-classification metal loss depth sizing accuracy of gouge and corrosion features will also be presented. Finally, an overview of the operational benefits of the enhanced gouge classifier results will be provided.
Fracture Toughness Evaluation of Pre-1980’s Electric Resistance Welded Pipeline Seam Welds
Authors: Bagnoli Kenneth , Neeraj Thirumalai , Pioszak Greger , Holloman Ryan , Thorwald Gregory , Hay Clifford
Published: December 2022

In the 1950’s and 1960’s, economic expansion in Europe and North America led to significant growth in transmission pipeline capacity. Thus, many pipelines in operation today were constructed prior to 1980 and result in an aging pipeline infrastructure. An important mechanical integrity threat affecting oil and gas pipelines is the potential for fast fracture of longitudinal seam welds. A major factor affecting fast fracture resistance involves the welding practices used prior to 1980. The most common method was low-frequency electric resistance welding (LF-ERW). Imperfections were more prevalent using LF-ERW compared with modern high-frequency electric resistance welding (HF-ERW), employed for the last 40 years. Another important factor is the steel quality produced during this era. High tramp element levels, particularly sulfur, led to lower and more variable fracture toughness than steels produced after about 1980. To effectively manage the risk of fast fracture a strong statistical understanding of quasi-static fracture toughness in pipeline steels is important but has been lacking. To advance integrity management of existing pipeline systems, the fracture toughness of vintage pipeline materials has been characterized by conducting 550 fracture toughness tests, collecting data from literature sources (25) [1] [2], and test results supplied from a secondary pipeline operator (45), for a total dataset of 620. The testing program included a wide range of manufacturers and fabrication years based on sampling over 30 individual pipelines. The results suggest that it is possible to treat pre-1980 pipeline steels/welds as a single cohort. This is valuable since toughness data for individual pipelines are often insufficient or not available. The test data was analyzed to provide input for either a deterministic or probabilistic analysis. Consideration for the constraint effects of specimen geometry was also investigated to address the transferability of test results to an axially oriented flaw in a thin walled 0.2–0.4in (5–10 mm) pipeline. Constraint was characterized by using J-Q and J-A2 theory in a 3D FE simulation. Finally, analysis of the weld microstructure provided fundamental insight into the operative fracture mechanisms responsible for their toughness properties.
Forced Resonance Imaging for 3-D Mapping of Underground Pipeline Assets
Authors: Xu Tianzong (David) , Bakhtar Khosrow
Published: December 2022

Applications of a novel 3-D mapping and visualization technology for mapping underground natural gas plastic/metallic pipelines and improving pipeline assets management beyond the capability of other known technologies are presented. The developed technology is based on combining Radar and Forced-Resonance-Imaging (FRI) principles referred to as the Bakhtar Buried Pipe Detector (BPD) with its original platform developed under US Air Force SBIR programs referred to as “BakhtarRadar”. This extremely low-power (≤ 10 dBm) detection and volumetric imaging technology defines a new rapid and cost-effective approach that uses the ability of casing and related embedded contents to absorption of RF energy in certain quantum emission frequency bands as a means of determining their presence. Furthermore, it uses the absorbed energy to differentiate between buried metallic and plastic pipes and reconstruct 3-D volumetric images from buried targets.

The above-ground survey is conducted by scanning the application-specific sensor head (FR antennae) over the area of interest at controlled speed rate of 5–30 centimeters per seconds depending on the buried pipeline size, collecting sub-surface data, detecting the buried pipeline location followed by constructing 3-D mapping volumetric images in a rapid succession. The results provide uniquely defined high-resolution information on location and alignment, depth, type (metallic and/or plastic pipes), and dimensional details of buried pipelines. The field calibration and blind testing at PG&E’s service territory demonstrate BPD’s capability of collecting, screening, analyzing, managing, as well as integrating pipeline location data from multiple sources, such as utility operators, locating service providers, etc.
A Deep Dive Into the Use of LiDAR Change Detection Analysis for Regional Landslide Monitoring in the Appalachian Basin Region of the US
Authors: Theriault Bailey , Markley Christopher , Metzger Tara
Published: December 2022

This paper will provide an overview of a monitoring approach that has proven critical for the long-term monitoring and assessment of high-density landslide areas along pipelines at a regional or system-wide scale: the use of repeat Light Detection and Ranging (LiDAR) surveys (i.e., LiDAR Change Detection Analysis). The strength of using LiDAR is the ability to “see” through trees and vegetation and produce a bare earth digital elevation model of a given slope. As such, LiDAR is one of the most powerful tools for identifying landslides where tree cover is present, such as in the Appalachian Basin region. Repeated acquisition of LiDAR data over time while encompassing the same area can be used for the identification of new or developing landslides, as well as for monitoring movement within known landslides. LiDAR Change Detection Analysis compares successive LiDAR datasets and shows the apparent changes in elevation between the two datasets. By comparing the ground elevations between two datasets, areas where ground movement has occurred since the previous dataset can be identified. This information can aid in identifying, revising, and prioritizing potential landslide threats over large areas.

A case study will be presented from the Appalachian Basin region of the United States, where there exists a high incidence of landslides. The case study will discuss how LiDAR Change Detection Analysis was used each year over a 4-year period along approximately 1,400 miles of pipeline to monitor for landslide movement and formation. The case study will summarize the total number per year and average number per mile of right-of-way per year, of landslides with indications of movement as well as newly identified landslides. In addition, the case study will explore possible correlations between annual regional precipitation and annual landslide movement.
Development of an Interactive E-Learning Geohazards Training Program for Pipeline Operations Personnel
Authors: Brant Logan , Zawacki Todd , Barnes Jane , McKenzie-Johnson Alexander
Published: December 2022

Geohazards on pipeline right-of-way have the potential to threaten pipeline integrity and pose safety and environmental risks. Identification of geohazard sites is a necessary first step in the management of geohazards. Geohazard identification should be accomplished with a multi-dimensional approach that includes a combination of subject matter expert assessment, field observations by pipeline operations personnel, in-line inspections and aerial patrols. Pipeline operations personnel may require additional training to effectively perform this important function.

This paper describes a collaboration between an engineering consultant and a pipeline operator on the development of an hour-long interactive e-learning geohazards training program specifically designed for pipeline operations personnel. The development began by clearly establishing the learning objectives, the target audience, and the delivery format for the training. Topics covered in the training include why geohazards management is important for pipeline operations, common types of geotechnical, hydrotechnical, and third-party geohazards encountered on pipeline right-of-way, signs during field observations that may indicate the presence of potential geohazards and how to document and report field observations of potential geohazards.

The training was illustrated throughout with photographs showing real-world examples of geohazards on pipeline right-of-way. These photographs were contributed by subject matter experts who frequently perform field identification, assessment, monitoring and design mitigation measures for geohazards on pipeline right-of-way. The team prepared written narration read by a professional narrator. Additionally, the team prepared a series of ungraded knowledge check questions incorporated throughout the presentation and a graded 10-question course examination taken after completing the training to confirm participant comprehension. The final step of the development involved transitioning the course to Articulate Storyline software to allow for the course to be taken online. The training has been uploaded and integrated into the pipeline operator’s learning management system.

This paper shares the steps that went into developing this interactive e-learning geohazards training program and the operations improvements expected as a result of the expanded geohazard identification training for pipeline operations personnel.
Influence of Strain Hardening Model on the CorLAS™ Model for Cracked Pipelines
Authors: Zhang Xinfang , Lin Meng , Kainat Muntaseer , Yoosef-Ghodsi Nader , Leung Juliana Y. , Adeeb Samer
Published: December 2022

Underground steel pipelines may experience failure due to the occurrence of cracks or crack-like anomalies as a result of internal and external factors such as manufacturing imperfection and geotechnical movement. Metallic materials like steel often undergo strain hardening as deformation increases. The strain hardening characteristics of materials are usually described by strain hardening models. Accurate approximations of the stress-strain curves are essential for numerical simulations. For pipelines containing longitudinally-oriented cracks, a software-based model often referred to as CorLAS™ is widely accepted and commonly used by the pipeline industry to estimate the failure pressures. In CorLAS™, the stress-strain behavior of pipeline steel is modeled based on a simple power-law relationship known as the Hollomon equation. However, the Hollomon model cannot characterize the full-range strain hardening behavior of metallic materials, which is an approximation by design. Additionally, the strain-hardening exponent, n, in the CorLAS™ model is estimated based on an expression using yield strength and ultimate tensile strength. By contrast, the n value in mathematical models such as the Ramberg-Osgood equation, Swift equation, Ludwik equation, Ludwigson equation can be evaluated by using curve-fitting regression techniques, i.e., fitting the experimental true stress versus true strain data to the empirical models. This paper reviews the most frequently used strain hardening formulas and explores the applicability and accuracy of these stress-strain models including the hardening exponent expression in CorLAS™ (Version 2). This is followed by a sensitivity study to investigate the effect of n on the failure pressure predicted by CorLAS™. The holistic accuracy of CorLAS in predicting burst pressure, compared to other widely accepted models, is not explored.
Management System Enabled ESG Performance
Authors: Jean Mark S. , Grant Eric
Published: December 2022

Throughout the centuries, companies have faced a wide range of challenges and changes that have caused them to rethink their strategies and redesign their organizations. The recent focus on environmental, social, and governance (ESG) performance is one of the new challenges facing companies today. ESG builds on prior Corporate Social Responsibility (CSR) reporting, adding additional structure and rigour to the process for disclosure. It is not the concept of ESG that is challenging, but the speed at which the public and other key stakeholders, including institutional investors and regulators, have endorsed it that creates the greatest issue for companies. It has affected their ability to attract investment, increases costs for borrowing as well as for insurance. This directly impacts a company’s ability to finance and get access to lower-cost capital for their growth and ongoing operations[1].

There are many different disclosure frameworks in place to support ESG improvement and reporting. These include including Global Reporting Initiative (GRI), Sustainability Accounting Standards Board (SASB), Task Force on Climate-related financial Disclosures (TCFD), United Nations (UN) Sustainability Goals, etc. with new frameworks being added and changes being made on a regular basis. While there are many different frameworks, many share a common objective of improved performance in one or more of the ESG pillars. This improvement is not intended to be acute, but rather demonstrate continual organizational improvement over time. To effectively meet ESG requirements, companies will have to demonstrate sustained improvements in defined ESG pillars, supported by:

• Defined ESG strategies;

• Established processes and consistent and progressive practices;

• Measurement, reporting, and leadership oversight; and

• Disclosure/Transparency (e.g. public reporting)[2]

As the recognition of ESG continues to grow, so too has the use of management systems, especially in the pipeline industry. Many companies are developing or have developed a management system to support their organization and operations. This is one of the key tools that companies can use to systematically improve their ESG performance. It provides the structure to support effective ESG risk identification, management, mitigation, and reporting, providing the necessary sustained improvement and governance oversight needed. Through a management system plan-do-check-act (PDCA) approach, ESG initiatives can be effectively planned, executed, reviewed, and reported to support ongoing improvement in both ESG as well existing operations.

The proposed paper will discuss the relationship between management systems and ESG how to leverage a management system to support systematic improvements in ESG performance and year-over-year improvement in ESG related metrics.
Assessing Internal Pitting Corrosion With Encoded Ultrasonic Scanning
Authors: Chen Joe , Li Yanping , Place Trevor , Aulin Axel , Galbraith Logan
Published: December 2022

Internal corrosion is one of the main threats to pipeline integrity. For in-line inspection (ILI) based integrity programs, in-the-ditch non-destructive examination (NDE) data quality is imperative for ILI validation. NDE feature misclassification and/or depth inaccuracy can lead to unnecessary integrity actions such as unnecessary excavations, more frequent ILI, or increased risk to system integrity. Therefore, it is critical to ensure the accuracy of NDE data.

Ultrasonic Testing (UT) technology is the primary method to detect, characterize, and measure internal corrosion during in-ditch NDE. While studies have been conducted to understand various NDE technologies and capabilities associated with detecting, sizing, and classifying crack and external corrosion indications, less work has been published regarding field evaluation of internal corrosion indications.

In this study, real cases of liquid pipelines will be used to demonstrate the challenges in detecting, characterizing and sizing internal corrosion using current UT technologies. The cases show that improper NDE technique selection triggered additional excavations or caused internal corrosion to be non-conservatively under-reported. This work also includes various UT technologies, such as encoded zero-degree UT scanning, manual zero-degree UT testing, encoded Phased Array Ultrasonic Testing (PAUT), and Time of Flight Diffraction (TOFD) for characterizing and sizing both natural and machined defects in pipe and plate samples. High-resolution laser scans using Creaform HandyScan technology are used to verify actual feature depth. Depth sizing accuracy of each technology is established using statistical analysis. In order to determine detection limits of the above technologies, tests are performed on pitting and inclusion of various sizes, ranging from 8 mm to 0.5 mm in diameter.

This study will assist in establishing the limitations of current UT NDE technologies and recommendations to develop best practices for obtaining quality field NDE data from pipeline excavations for internal corrosion.
Performance of Five Different Natural Gas and Hydrogen Blending Mixer Designs via CFD
Authors: Botros Kamal K. , Shariati Mohammad , Sandhawalia Swaran
Published: December 2022

The aspiration for blending hydrogen (H2) into natural gas (NG) in gas transmission systems is high and is happening globally. However, the mechanics and details of blending the two streams are not well developed or perfected. There is a need to arrive at the best technique and approach to achieve perfect blending to minimize the potential adverse impact on the operation of downstream facilities as well as on the end-users. The challenge is primarily driven by the fact that NG and H2 have vastly different properties, principally densities, that may lead to possible stratification, short circuiting, and pockets of undesirable high concentration of H2 in the blended stream. The paper documents Computational Fluid Dynamics (CFD) simulation results conducted on five different concepts of mixer/blending designs. These mixer designs are: i) single or multiple side entries, ii) dual spiral ribbon (DSR) type mixer, iii) venturi mixer, iv) hybrid mixer of DSR inside a venturi, and v) NC5 perforated tube bundle type mixer. An example of an NPS 12 (DN300) ultrasonic meter run with an NPS 20 (DN500) header was assumed throughout the analysis. It was found that the venturi mixing concept with a single side entry is the optimum design due to its simplicity, cost effectiveness, and relatively low pressure drop. With this simple design, 99% mixing efficiency is achieved within 13D at maximum flow, where D is the main header diameter downstream of the mixing station. The pressure drop coefficient for this design is estimated to be approx. 3.1, which amounts to ∼6 kPa at maximum flow, which is relatively low. However, mixing will halt at coefficient of variance = 0.2 (80% mixing efficiency) at very low flow rate of a turndown ratio of 20:1. Final selection of a mixer design from the five designs investigated depends on the tradeoff between mixing efficiency, pressure drop and cost.
Research on an Automated Process to Automatically Correlate ILI Features With NDT Laser Scans
Authors: Brush Ron , Westrick Pat , Xiang Wei , Dooley Colin , Huang Terry
Published: December 2022

New Century Software has completed a research and development project in collaboration with TC Energy to automatically correlate ILI corrosion features with corresponding NDT laser scan data to validate ILI depth predictions with raw laser scan pit measurements and generate unity plots.

The research project utilized a process that New Century developed that automatically compares ILI features with NDT 3D laser scan measurements to generate unity plots. This process automatically reads the ILI pipe tally reports and generates GIS graphics representing the pipe surface using actual pipe length and diameter dimensions. The process automatically reads raw laser scan data and overlays this data on the GIS pipe surface. The program automates an optimization algorithm that seeks to align the ILI features with the laser data to account for measurement differences between the ILI tool and the laser scan report. Each ILI feature is aligned and used to calculate the measured maximum depth. The ILI predicted depths and the laser measured depths are represented by a unity plot that illustrates the correlation of ILI-predicted features with 3D laser scan measured features. The goal of this project was to identify the best technical approach to automatically match these data and to provide recommendations to TC Energy through testing the technique on a large amount of data and fine-tuning the configuration settings in the algorithm. Also, quantitative approaches were developed and implemented to evaluate the automatically-generated unity plots.

Automating this process will save significant time and cost over manual correlation methods and provide pipeline operators with information about the quality of ILI inspections from different vendors. It could also be used to create a bias factor for ILI Corrosion Growth Rate assessment as well as inform the pipeline risk assessment model.