Challenging the Industry Practices of Temperature Distribution, SIF and its Effects on Piping Design

2020 ◽  
Author(s):  
Gaurav Bhende ◽  
Amit Jagdale ◽  
Jitendra Patel
Keyword(s):  
Temperature Distribution ◽  
Real Life ◽  
Effect Of Temperature ◽  
Piping System ◽  
Design Basis ◽  
Process Plant ◽  
Rating Factor ◽  
Stress Intensification Factor ◽  
Practical Analysis ◽  
The Cost

Abstract The piping, welding and its fittings contributes to around 25–35% of the total material [1] of any process plant. The quantity of the piping and fittings required in critical pipes (lines) is largely influenced by the flexibility requirements to comply with applicable codes. Since the pressure and weight driven stresses are primary in nature and taken care by the thickness & supports respectively. The Secondary stresses are mainly caused due to temperature and determines the route of the pipe. Unfortunately, there is no sufficient awareness amongst the Process engineers, who dictate the temperature, about the effect of temperature (listed in line list) on the plant cost. To make the situation worse, very often the pipe stress engineers follow thumb rules, conservative design basis while applying temperature to pipes without questioning process engineers the basis and without having experimental evidences which in turn ends up adding to the cost, labor and time of the plant. Another factor influencing the ‘flexibility need’ is ‘Stress Intensification Factor’ which, as well, incorrectly multiplied by conservative numbers, especially in case of 45° branch fittings. Even ‘Flange leakage analysis’ needs to be performed to ensure safety of the plant. This paper challenges the mis-concepts in temperature distribution of a piping system by analyzing a real-life problem. Also, it provides the actual temperature measurements and compares it with theoretical values. At the end it provides a ‘Temperature de-rating factor, @(Taa)’ which can be used to derive actual expected temperature distribution. Further this paper provides a table to get the actual SIF of Tee and Fittings obtained by FEA. At the end it provides comparison between the results obtained by present industry practices against practical analysis and its effect on cost.

scholarly journals Simulation of Thermal and Electric Field Distribution in Packaged Sausages Heated in a Stationary Versus a Rotating Microwave Oven

Foods ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1622
Author(s):  
Wipawee Tepnatim ◽  
Witchuda Daud ◽  
Pitiya Kamonpatana
Keyword(s):  
Temperature Distribution ◽  
Electric Field ◽  
Three Dimensional ◽  
Development Stage ◽  
Microwave Oven ◽  
Computational Time ◽  
Plastic Package ◽  
Heating Uniformity ◽  
The Cost ◽  
Good Agreement

The microwave oven has become a standard appliance to reheat or cook meals in households and convenience stores. However, the main problem of microwave heating is the non-uniform temperature distribution, which may affect food quality and health safety. A three-dimensional mathematical model was developed to simulate the temperature distribution of four ready-to-eat sausages in a plastic package in a stationary versus a rotating microwave oven, and the model was validated experimentally. COMSOL software was applied to predict sausage temperatures at different orientations for the stationary microwave model, whereas COMSOL and COMSOL in combination with MATLAB software were used for a rotating microwave model. A sausage orientation at 135° with the waveguide was similar to that using the rotating microwave model regarding uniform thermal and electric field distributions. Both rotating models provided good agreement between the predicted and actual values and had greater precision than the stationary model. In addition, the computational time using COMSOL in combination with MATLAB was reduced by 60% compared to COMSOL alone. Consequently, the models could assist food producers and associations in designing packaging materials to prevent leakage of the packaging compound, developing new products and applications to improve product heating uniformity, and reducing the cost and time of the research and development stage.

Investigation Into Thermal Stress Characteristics of Pipe-in-Pipe Under High Temperature Condition

2018 ◽  
Author(s):  
Si-Hwa Jeong ◽  
Min-Gu Won ◽  
Nam-Su Huh ◽  
Yun-Jae Kim ◽  
Young-Jin Oh ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Thermal Stress ◽  
High Temperature ◽  
Temperature Distribution ◽  
Heat Transfer Analysis ◽  
Piping System ◽  
Curved Pipe ◽  
High Temperature Condition ◽  
Single Pipe ◽  
Radiation Conditions

In this paper, the thermal stress characteristics of the pipe-in-pipe (PIP) system under high temperature condition are analyzed. The PIP is a type of pipe applied in sodium-cooled faster reactor (SFR) and has a different geometry from a single pipe. In particular, under the high temperature condition of the SFR, the high thermal stress is generated due to the temperature gradient occurring between the inner pipe and outer pipe. To investigate the thermal stress characteristics, three cases are considered according to geometry of the support. The fully constrained support and intermediate support are considered for case 1 and 2, respectively. For case 3, both supports are applied to the actual curved pipe. The finite element (FE) analyses are performed in two steps for each case. Firstly, the heat transfer analysis is carried out considering the thermal conduction, convection and radiation conditions. From the heat transfer analysis, the temperature distribution results in the piping system are obtained. Secondly, the structural analysis is performed considering the temperature distribution results and boundary conditions. Finally, the effects of the geometric characteristics on the thermal stress in the PIP system are analyzed.

scholarly journals Managing cost uncertainties in transportation and assignment problems

1998 ◽  
Vol 2 (1) ◽  
pp. 65-104 ◽  
Author(s):  
V. Adlakha ◽  
H. Arsham
Keyword(s):  
Time Lag ◽  
Real Life ◽  
Optimal Solution ◽  
Global Market ◽  
Solution Algorithm ◽  
Assignment Problems ◽  
The Stability ◽  
Order Assignment ◽  
Cost Parameters ◽  
The Cost

In a fast changing global market, a manager is concerned with cost uncertainties of the cost matrix in transportation problems (TP) and assignment problems (AP).A time lag between the development and application of the model could cause cost parameters to assume different values when an optimal assignment is implemented. The manager might wish to determine the responsiveness of the current optimal solution to such uncertainties. A desirable tool is to construct a perturbation set (PS) of cost coeffcients which ensures the stability of an optimal solution under such uncertainties.The widely-used methods of solving the TP and AP are the stepping-stone (SS) method and the Hungarian method, respectively. Both methods fail to provide direct information to construct the needed PS. An added difficulty is that these problems might be highly pivotal degenerate. Therefore, the sensitivity results obtained via the available linear programming (LP) software might be misleading.We propose a unified pivotal solution algorithm for both TP and AP. The algorithm is free of pivotal degeneracy, which may cause cycling, and does not require any extra variables such as slack, surplus, or artificial variables used in dual and primal simplex. The algorithm permits higher-order assignment problems and side-constraints. Computational results comparing the proposed algorithm to the closely-related pivotal solution algorithm, the simplex, via the widely-used pack-age Lindo, are provided. The proposed algorithm has the advantage of being computationally practical, being easy to understand, and providing useful information for managers. The results empower the manager to assess and monitor various types of cost uncertainties encountered in real-life situations. Some illustrative numerical examples are also presented.

Fatigue Evaluation for Thermally Stratified DVI Piping

2012 ◽  
Author(s):  
Hwan Ho Lee ◽  
Joon Ho Lee ◽  
Dong Jae Lee ◽  
Seok Hwan Hur ◽  
Il Kwun Nam ◽  
...  
Keyword(s):  
Temperature Distribution ◽  
Thermal Stratification ◽  
Nuclear Power ◽  
Heat Removal ◽  
Local Stress ◽  
Piping System ◽  
Hydraulic Analysis ◽  
Fatigue Evaluation ◽  
Core Cooling ◽  
Thermal Hydraulic Analysis

A numerical analysis has been performed to estimate the effect of thermal stratification in the safety injection piping system. The Direct Vessel Injection (DVI) system is used to perform the functions of Emergency Core Cooling and Residual Heat Removal for an APR1400 nuclear power plant (Korea’s Advanced Power Reactor 1400 MW-Class). The thermal stratification is anticipated in the horizontally routed piping between the DVI nozzle of the reactor vessel and the first isolation valve. Non-axisymmetric temperature distribution across the pipe diameter induced by the thermal stratification leads to differential thermal growth of the piping causing the global bending stress and local stress. Thermal hydraulic analysis has been performed to determine the temperature distribution in the DVI piping due to the thermal stratification. Piping stress analysis has also been carried out to evaluate the integrity of the DVI piping using the thermal hydraulic analysis results. This paper provides a methodology for calculating the global bending stresses and local stresses induced by the thermal stratification in the DVI piping and for performing fatigue evaluation based on Subsection NB-3600 of ASME Section III.

scholarly journals Beyond The Historiography: Film Dokumenter Sejarah Sebagai Alternatif Historiografi di Indonesia

2018 ◽  
Vol 2 (2) ◽  
pp. 405
Author(s):  
Aan Ratmanto
Keyword(s):  
New Media ◽  
Documentary Film ◽  
Real Life ◽  
Documentary Films ◽  
Digital Era ◽  
History Of ◽  
The Cost ◽  
The University ◽  
Quality Of Research

The Department of History, Faculty of Cultural Sciences, the University of Gadjah Mada in 2015 made a milestone in the development of historiography in Indonesia. They made a bold move to produce a scholar with a documentary film work instead of a thesis. In the future, it is not impossible that this step will soon be followed by other universities in Indonesia. This paper was written in response to these developments. In this digital era-and in the midst of still low interest in reading in Indonesia-emerged the discourse to seek new media for historiography in Indonesia. The film, especially documentary films are seen as new media that match the characteristics of history because of they both present real-life reality. Moreover, Indonesia with the diversity of tribes and culture and history, of course, save a variety of themes that will not run out to be appointed a documentary. Based on that, this paper will discuss the types, forms, and format of the documentary that is suitable and possible to be produced by history students as a substitute for thesis-considering the cost of film production tends to be higher than thesis research. Thus, the film of a documentary a college student, especially a history produces the quality of research and aestheticsKata 

scholarly journals Finite Element Analysis of Temperature Distribution and Stress Behavior of Squeeze Pressure Composites

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
P. Gurusamy ◽  
T. Sathish ◽  
V. Mohanavel ◽  
Alagar Karthick ◽  
M. Ravichandran ◽  
...  
Keyword(s):  
Finite Element ◽  
Temperature Distribution ◽  
Cooling Rate ◽  
Base Alloy ◽  
Cast Alloy ◽  
Simulation Software ◽  
Engineering Industry ◽  
Effect Of Temperature ◽  
Cooling Curves ◽  
Squeeze Pressure

Aluminium-reinforced composites play a vital role in the engineering industry because of their better strength and stiffness. The properties are directly related to the solidification phenomenon of the cast alloy. The design engineer should understand the importance of the solidification behavior of base alloy and its reinforcement. Composites’ solidification study is rare, and the reviews are limited. The solidification process is analyzed using the finite element method (FEM), and this would fetch a lot of information about the cooling rate of the composites and also helps to reduce the time in experimentation. This paper reports and plots the cooling curves of Al/SiCp composites using simulation software. Cylindrical-shaped composites were developed using the squeeze casting method, and the experimental cooling curves were plotted using a K-type thermocouple. Composites samples were prepared at the following squeeze pressures: 0, 30, 50, 70, 100, and 130 MPa; melt and die temperature was kept constant at 800 and 400°C, respectively. The experimental and FEA cooling curves were compared, and it was agreed that the increase in the squeeze pressure increases the cooling rate of the developed composite. Furthermore, the effect of temperature distribution from the inner region of the melt and die material which causes the radial and tangential stress of components has also been examined.

Bidder Selection in Public Procurement using a Fuzzy Decision Support System

Fuzzy Systems ◽  
2017 ◽  
pp. 1620-1642
Author(s):  
Vjekoslav Bobar ◽  
Ksenija Mandic ◽  
Milija Suknovic
Keyword(s):  
Decision Support ◽  
Decision Support System ◽  
Support System ◽  
Public Procurement ◽  
Real Life ◽  
Case Scenario ◽  
Uncertain Variables ◽  
Public Money ◽  
Fuzzy Extent Analysis ◽  
The Cost

Bidder selection in public procurement is a decision making problem whose primary purpose is to achieve the cost effectiveness and efficiency in the expenditure of public money. This principle is also known as the principle of “value for money”. This selection is based on many alternatives and many quantitative and qualitative criteria where qualitative criteria are often expressed as linguistic uncertain variables. The theory of fuzzy sets is a tool suitable to model uncertainty when applied to a variety of problems in real life. However, many fuzzy methods require complex calculation and they are not appropriate for using in public procurement because they slow down this process. In this paper, in order to make a quick decision in public procurement, a Decision Support System based on the fuzzy extent analysis method is developed. In order to demonstrate the usefulness of this system, a real-life case scenario of public procurement is presented.

scholarly journals Lower bound for the cost of connecting tree with given vertex degree sequence

2019 ◽  
Vol 8 (2) ◽  
Author(s):  
Mikhail Goubko ◽  
Alexander Kuznetsov
Keyword(s):  
Lower Bound ◽  
Heuristic Algorithms ◽  
Degree Sequence ◽  
Real Life ◽  
Inequality Constraints ◽  
Topology Design ◽  
Semidefinite Optimization ◽  
Linear Matrix ◽  
Matrix Inequality ◽  
The Cost

Abstract The optimal connecting network problem generalizes many models of structure optimization known from the literature, including communication and transport network topology design, graph cut and graph clustering, etc. For the case of connecting trees with the given sequence of vertex degrees the cost of the optimal tree is shown to be bounded from below by the solution of a semidefinite optimization program with bilinear matrix inequality constraints, which is reduced to the solution of a series of convex programs with linear matrix inequality constraints. The proposed lower-bound estimate is used to construct several heuristic algorithms and to evaluate their quality on a variety of generated and real-life datasets.

4.4 A Policy for Encouraging the Effective Use of Computers in Animal Production Development

1981 ◽  
Vol 5 ◽  
pp. 137-140
Author(s):  
C. T. Whittemore
Keyword(s):  
Cost Effectiveness ◽  
Real Life ◽  
Simulation Models ◽  
Agricultural Industry ◽  
Flat Rate ◽  
Wide Range ◽  
Business Forecasting ◽  
Development Workers ◽  
Effective Use ◽  
The Cost

In addition to data and record handling and the completion of complex and arduous mathematical calculations, the computer may serve a wide range of purposes for the agricultural industry; these include the provision of day-to-day management information, the mechanical enactment of management decisions, business forecasting, interpretation of real life and prediction of future response by use of simulation models, analysis of cost effectiveness of various tactics and stratagems, the transfer of information, scrutinization of existing knowledge and the formulation of experimental programmes. The computer is seen as a major linking medium between research, development and production practice; being both the preferred route for information flow and an ideal way of packaging dispersed pieces of knowledge into practical, usable, systems advice.The concern of practical producers is not with discrete little problems but with systems. To help, the extension worker must bring forward systems solutions. Often research and development workers try to get across to producers potential benefits in small bits (3 times daily milking gives a yield lift of 15%; flat rate feeding gives better margins over concentrates; high density diets improve feed efficiency), whereas producer benefits come from the cost effectiveness of whole integrated systems.

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