Development of the Risk Based Guidelines for Natural Gas Transmission Pipelines Projects

2008 ◽  
Author(s):  
Ca´ssia Cardoso ◽  
Luiz Fernando de Oliveira ◽  
Denise Faertes
Keyword(s):  
Design Guidelines ◽  
Gas Pipeline ◽  
Management Tool ◽  
Design Parameters ◽  
Risk Level ◽  
Gas Pipelines ◽  
Design Standards ◽  
Natural Gas Transmission ◽  
Risk Acceptability ◽  
The Impact

The design standards of gas pipeline NBR 12712 and ASME B31.8, although having their own safety factors, had not incorporated explicitly the risk concept for the population in their definitions. However, the orientation of the Brazilian Environment Agencies is that the risk level of transportation activity for gas pipelines must be controlled to the health and the safety of the population. These facts can create a critical management situation because a gas pipeline can be in compliance with the design standards and not in relation to the criteria of the Environment Agencies. In this scenario, the establishment of risk based design guidelines becomes an essential action. In this article, a methodology for the elaboration of these guidelines is presented. We analyze not only the influences of the main operational and design parameters on the risk, but also the impact of the main risk acceptability criteria for the approval of the gas pipelines operation license. The result of this article is an excellent decision management tool on the management and the viability evaluation of this type of project and its application provides important technical knowledge to definitions of routes, operational and design parameters, and the optimized selection of risk reduction measures.

A performance investigation of small-bore sewers

2007 ◽  
Vol 55 (4) ◽  
pp. 85-91 ◽  
Author(s):  
F.A. Memon ◽  
A. Fidar ◽  
K. Littlewood ◽  
D. Butler ◽  
C. Makropoulos ◽  
...  
Keyword(s):  
Physical Model ◽  
Water Cycle ◽  
Design Guidelines ◽  
Design Parameters ◽  
New Developments ◽  
Tissue Paper ◽  
Solids Transport ◽  
Implementation Methodology ◽  
Gradient Variation ◽  
The Impact

This paper describes a full-scale physical model and its application to investigate the effectiveness/performance of small-bore sewers for a range of operational and design parameters. The implementation methodology involves observing the movement of synthetic gross solids in three small bore sewers (150, 100 and 75 mm diameter) for different volumes of simulated flush waves and gradients. The simulated flush waves were generated, using an automated wave sequencer, for three different flush volumes (3, 4.5 and 6 litres). To investigate the impact of solid shape factor, a number of tests were carried out using synthetic solids in combination with toilet tissue paper. In total, more than 1,000 tests were performed for different operational and design parameter combinations. Results obtained to date have confirmed earlier studies, particularly with respect to the role of flush volume in solids transport, and identified the impact of gradient variation and its significance particularly in small-bore sewers receiving low flush volume. Results from the physical model application exercise will be used to propose new design guidelines for wastewater collection systems with specific consideration to new developments and inform the decision support system, currently being developed as part of a research project on water cycle management for new developments (WaND).

Development of an Exhaust Manifold Design Optimization for Cylinder Scavenging and Turbocharger Performance

2010 ◽  
Author(s):  
Diana K. Grauer ◽  
Kirby S. Chapman
Keyword(s):  
Research Team ◽  
Nox Reduction ◽  
Design Guidelines ◽  
Design Parameters ◽  
Exhaust Manifold ◽  
Engine Operation ◽  
Operating Range ◽  
Pressure Pulses ◽  
Scavenging Efficiency ◽  
The Impact

This paper presents an investigation into the NOX reduction role played by the exhaust manifold of large-bore two stroke cycle engines by exploring the impact of the exhaust manifold design on turbocharger and engine operation. Exhaust manifold performance is defined as the ability of the exhaust manifold to: 1) optimize cylinder scavenging efficiency; and 2) minimize the pressure differential between the compressor discharge and the turbine inlet by exploiting the blow-down pressure pulses and minimizing the static pressure gradient along the exhaust manifold. Pressure pulses in the exhaust manifold have been identified as a plausible mechanism that hinders efficient cylinder scavenging and turbocharger operating range. While modifying the ports and manifold may not be cost effective, a complete understanding of and the ability to address the impact of these pressure waves on turbocharger performance and scavenging efficiency will lead to more reliable engine upgrade projects as the industry approaches the 0.5 g/bhp-hr engine. The research team chose “available energy,” or the amount of mechanical and thermal energy available to the turbocharger turbine for operation as the parameter for defining optimal exhaust manifold design parameters. This allowed the research team to: 1) investigate energy losses in the candidate Clark TLA-6 exhaust removal system on a component basis, and 2) translate the mitigation of these losses into expanded turbocharger operating range. The end point of the project was a set of exhaust manifold design guidelines aimed at maximizing turbocharger performance by way of the defined metrics, scavenging efficiency and waste-gate margin.

Study on Acceptable Risk for Oil and Gas Pipelines in China

2010 ◽  
Author(s):  
Hua Zhang ◽  
Jinheng Luo ◽  
Juanli Chen ◽  
Xinwei Zhao ◽  
Guangli Zhang
Keyword(s):  
Risk Assessment ◽  
Oil And Gas ◽  
Gas Pipeline ◽  
Risk Level ◽  
Gas Pipelines ◽  
Acceptable Risk ◽  
Risk Criteria ◽  
Oil And Gas Pipelines ◽  
Integrity Management

Risk assessment is basis to put pipeline integrity management in practice and the acceptable risk level is important criteria to execute risk assessment and constitute maintenance safeguard. So it is very important to establish a rational and practicable acceptable criterion and present a specific acceptable risk level. It is just for this need that the present paper gave a review of all the available research around the acceptable risk level and analyzed various domestic and overseas standards and documentation concerning how to define the acceptable risk criteria. As a result, a criterion suitable for oil and gas pipeline was presented and recommended acceptable risk level was gave.

scholarly journals Design Guidelines for Axial Turbines Operating With Non-Ideal Compressible Flows

2020 ◽  
Author(s):  
Andrea Giuffre’ ◽  
Matteo Pini
Keyword(s):  
Compressible Flows ◽  
Fluid Dynamic ◽  
Design Guidelines ◽  
Flow Coefficient ◽  
Design Parameters ◽  
Working Fluid ◽  
Stage Model ◽  
Turbine Stage ◽  
Similarity Equation ◽  
The Impact

Abstract The impact of non-ideal compressible flows on the fluid-dynamic design of axial turbine stages is examined. First, the classical similarity equation is revised and extended to account for the effect of flow non-ideality and compressibility. Then, the influence of the most relevant design parameters is investigated through the application of a dimensionless turbine stage model embedding a first-principles loss model. The results show that the selection of optimal duty coefficients is scarcely affected by the molecular complexity of the working fluid, whereas compressibility effects produce an offset in the efficiency trends and in the optimal flow coefficient. Furthermore, flow non-ideality can lead to either an increase or a decrease of stage efficiency of the order of 2–3% relative to turbines designed to operate in dilute gas state. This effect can be predicted at preliminary design phase through the evaluation of the isentropic pressure-volume exponent. 3D RANS simulations of selected test cases corroborate the trends predicted with the reduced-order turbine stage model.

scholarly journals STUDY OF THE INFLUENCE OF COMPLEX MINING AND GEOLOGICAL CONDITIONS ON OPERATION TRANSIT PIPELINES

2020 ◽  
Vol 3 (156) ◽  
pp. 105-110
Author(s):  
O. Tarayevskiy
Keyword(s):  
Negative Impact ◽  
Internal Surface ◽  
Gas Pipeline ◽  
Stressful Situation ◽  
Gas Pipelines ◽  
High Background ◽  
The Earth ◽  
Individual Site ◽  
Geological Conditions ◽  
The Impact

On the basis of the system approach and analysis of the conditions of operation of transit main gas pipelines, analytical studies of the stresses occurring on the internal surface of the gas pipeline under the conditions of the obverse and reverse operation modes have been carried out. The method of determination (prognostication) of durability of long exploited pipelines, operated in complex mining and geological conditions was proposed. It was shown that during such exploitation of gas pipelines non-project modes are being found that require a detailed analysis of the use of their production capacities, and as a result it has been established that the study section in such conditions. The technique for determining the permissible level of arbitrarily oriented stresses acting on the investigated section of a gas pipeline with a complex technological structure and laid on a section with a disturbed equilibrium of the Earth is developed. It has been proved that the cyclic operation of pipelines and their structural elements in difficult geological conditions leads to an abnormally high background tension, which leads to a decrease in their predicted lifetime. It is proposed to carry out operational control of the stressed-deformed state of pipeline sections laid in complex mining and geological conditions and which have complex technological features. The principle of optimization of gas transportation by pipelines, passing in one technological corridor on the criterion of minimum negative impact on the environment was improved. The technique of determining the potential impact radius, which simultaneously takes into account the mode of operation of the gas pipeline, its actual technical condition, as well as the parameters of abnormal areas with disturbed equilibrium of the earth, was proposed. The developed method allows determining the necessary security zone on each individual site, in particular, to substantially reduce or increase it in relation to existing real conditions. In order to design new gas pipelines, there will be no pipelines in the same technological corridor, and for existing pipelines operated in the same technological corridor, it will be possible to reduce the impact of the emergency situation or even make it impossible because of optimal loading of the gas pipelines. The expediency of carrying out such experiments and the results obtained will allow to prevent accidents and failures of gas pipelines that lies in complex mining and geological conditions, to ensure their reliability during long service life as well. Keywords: gas, underemployment, stressful situation, density, mathematical model.

Evaluation of Interactions Between Thermal Piles Integrated in Building Foundations

2020 ◽  
Vol 1 (3) ◽  
Author(s):  
Byung Kwag ◽  
Moncef Krarti
Keyword(s):  
Three Dimensional ◽  
Design Guidelines ◽  
Interactive Effects ◽  
Design Parameters ◽  
Calculation Methods ◽  
Soil Medium ◽  
Operation Conditions ◽  
Heating And Cooling ◽  
Simplified Calculation ◽  
The Impact

Abstract This paper investigates the impact of thermal interactions between heat exchangers integrated within building foundation piles to meet space heating and cooling needs of buildings. Specifically, a three-dimensional transient numerical model is developed to evaluate the thermal performance of the foundation piles. The model is used to estimate the temperature variations within the soil medium under various operation conditions of thermo-active foundation (TAF) systems. Then, a series of parametric analyses is carried out to evaluate the influence of design parameters of the piles on the performance of TAF systems, including the interactive effects between piles as well as the impact of these piles on the building slab heat transfer. Then, the parametric analysis results are utilized to develop simplified calculation methods to assess the thermal impacts of the geometric features for the piles on both the performance of TAF systems as well as the building slab heat losses and/or gains. The developed simplified calculation methods are suitable to develop design guidelines in order to enhance the performance of thermal piles to heat and cool buildings.

On the Coupling of Inverse Design and Optimization Techniques for the Multiobjective, Multipoint Design of Turbomachinery Blades

2009 ◽  
Vol 131 (2) ◽  
Author(s):  
Duccio Bonaiuti ◽  
Mehrdad Zangeneh
Keyword(s):  
Design Method ◽  
Computational Cost ◽  
Three Dimensional ◽  
Design Strategy ◽  
Design Guidelines ◽  
Optimization Techniques ◽  
Inverse Design ◽  
Design Parameters ◽  
Turbomachinery Blades ◽  
The Impact

Automatic optimization techniques have been used in recent years for the aerodynamic and mechanical design of turbomachine components. Despite the many advantages, their use is usually limited to simple applications in industrial practice, because of their high computational cost. In this paper, an optimization strategy is presented, which enables the three-dimensional multipoint, multiobjective aerodynamic optimization of turbomachinery blades in a time frame compatible with industrial standards. The design strategy is based on the coupling of three-dimensional inverse design, response surface method, multiobjective evolutionary algorithms, and computational fluid dynamics analyses. The blade parametrization is performed by means of a three-dimensional inverse design method, where aerodynamic parameters, such as the blade loading, are used to describe the blade shape. Such a parametrization allows for a direct control of the aerodynamic flow field and performance, leading to a major advantage in the optimization process. The design method was applied to the redesign of a centrifugal and of an axial compressor stage. The two examples confirmed the validity of the design strategy to perform the three-dimensional optimization of turbomachine components, accounting for both design and off-design performance, in a time-efficient manner. The coupling of response functions and inverse design parametrization also allowed for an easy sensitivity analysis of the impact of the design parameters on the performance ones, contributing to the development of design guidelines that can be exploited for similar design applications.

scholarly journals Design Guidelines for Axial Turbines Operating With Non-Ideal Compressible Flows

2020 ◽  
Vol 143 (1) ◽  
Author(s):  
Andrea Giuffre' ◽  
Matteo Pini
Keyword(s):  
Compressible Flows ◽  
Control Volume ◽  
Fluid Dynamic ◽  
Three Dimensional ◽  
Design Guidelines ◽  
Design Parameters ◽  
Stage Model ◽  
Turbine Stage ◽  
Similarity Equation ◽  
The Impact

Abstract The impact of non-ideal compressible flows on the fluid-dynamic design of axial turbine stages is examined. First, the classical similarity equation (CSE) is revised and extended to account for the effect of flow non-ideality. Then, the influence of the most relevant design parameters is investigated through the application of a dimensionless turbine stage model embedding a first-principles loss model. The results show that compressibility effects induced by the fluid molecular complexity and the stage volumetric flow ratio produce an offset in the efficiency trends and in the optimal stage layout. Furthermore, flow non-ideality can lead to either an increase or a decrease of stage efficiency up to 3–4% relative to turbines designed to operate in dilute gas state. This effect can be predicted at preliminary design phase through the evaluation of the isentropic pressure–volume exponent. Three-dimensional (3D) RANS simulations of selected test cases corroborate the trends predicted with the reduced-order turbine stage model. URANS computations provide equivalent trends, except for case study niMM1, featuring a non-monotonic variation of the generalized isentropic exponent. For such turbine stage, the efficiency is predicted to be higher than the one computed with any steady-state model based on the control volume approach.

scholarly journals Parametric analysis of thin multifunctional elastomeric optical sheets

2018 ◽  
Vol 7 (4) ◽  
pp. 209-224
Author(s):  
Chloë Nicholson-Smith ◽  
George K. Knopf ◽  
Evgueni Bordatchev
Keyword(s):  
Light Source ◽  
Incident Light ◽  
Design Guidelines ◽  
Simulation Software ◽  
Design Parameters ◽  
Large Area ◽  
Optical Elements ◽  
Optical Refraction ◽  
Ray Tracing Simulation ◽  
The Impact

Abstract Flexible optical sheets are thin large-area polymer light guide structures that can be used to create innovative passive light-harvesting and illumination systems. The optically transparent micro-patterned polymer sheet is designed to be draped over arbitrary surfaces or hung like a curtain. The light guidance sheet is fabricated by bonding two or more micro-patterned layers with different indices of optical refraction. By imprinting micro-optical elements on the constituent layers, it is possible to have portions of the optical sheet act as a light concentrator, near ‘lossless’ transmitter, or diffuser. However, the performance and efficiency of the flexible optical sheet depends on the overall curvature (κ) of the optical sheet and the relative orientation of incident light source. To illustrate this concept, the impact of key design parameters on the controlled guidance of light through a two-layer polydimethylsiloxane (PDMS) concentrator-transmitter-diffuser optical sheet is investigated using ray tracing simulation software. The analysis initially considers a flat (κ=0) PDMS optical sheet exposed to a collimated light source. The impact of sheet curvature (κ>0) on both system efficiency and illumination uniformity is then briefly explored. Critical design guidelines for creating multifunctional monolithic optical sheets are also summarized.

Balanced Scorecard in the strategic planning of a construction company

2018 ◽  
Vol 1 (1) ◽  
pp. 1
Author(s):  
Roberth Frias ◽  
Maria Medina
Keyword(s):  
Strategic Planning ◽  
Strategic Management ◽  
Balanced Scorecard ◽  
Organization Theory ◽  
Management Control ◽  
Management Tool ◽  
The Balanced Scorecard ◽  
Construction Company ◽  
Construction Companies ◽  
The Impact

This research focused on the strategic management tool Balanced Scorecard and strategic planning, as a guide to guide the management of companies, allowing communication and the functionality of the strategy using KPIs that allow to identify, maintain control and increase efficiency and the achievement of optimal results. For the deductive hypothetical analysis, the specific factors that affect business management performance were grouped into two variables: Balanced Scorecard and Strategic Planning. The objective of the work was to demonstrate the impact of the Balanced Scorecard in the strategic planning of a construction company. In order to support the research, the following theories were approached: the Financial Theory, the Economic Theory of the Company, the Transaction Costs, the Network Theory, the Organization Theory, the Dependence on Resources, the Strategic Management Theory and the Business Diagnosis Theory. The result obtained confirms the hypothesis that there is a significant incidence of the Balanced Scorecard in the strategic planning of construction companies. In conclusion, the construction company has obtained significant improvements in the results in each of the indicators evaluated with the implementation of the Balanced Scorecard, demonstrating improvements in their management results, affirming that there is better performance and management control allowing them to achieve the organizational objectives set.

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