scholarly journals Formation Mechanism of Trailing Oil in Product Oil Pipeline

Processes ◽  
2018 ◽  
Vol 7 (1) ◽  
pp. 7 ◽  
Author(s):  
Enbin Liu ◽  
Wensheng Li ◽  
Hongjun Cai ◽  
Shanbi Peng
Keyword(s):  
Formation Mechanism ◽  
Diesel Oil ◽  
Flow Speed ◽  
Oil Pipeline ◽  
Computational Fluid Dynamics Cfd ◽  
The Dead ◽  
Predicted Values ◽  
New Equation ◽  
Mixed Oil

Trailing oil is the tail section of contamination in oil pipelines. It is generated in batch transportation, for which one fluid, such as diesel oil follows another fluid, such as gasoline, and it has an effect on the quality of oil. This paper describes our analysis of the formation mechanism of trailing oil in pipelines and our study of the influence of dead-legs on the formation of trailing oil. We found that the oil replacement rate in a dead-leg is exponentially related to the flow speed, and the length of the dead-leg is exponentially related to the replacement time of the oil. To reduce the amount of mixed oil, the main flow speed should be kept at about 1.6 m/s, and the length of the dead-leg should be less than five times the diameter of the main pipe. In our work, the Reynolds time-averaged method is used to simulate turbulence. To obtain contamination-related experimental data, computational fluid dynamics (CFD) software is used to simulate different flow rates and bypass lengths. MATLAB software was used to perform multi-nonlinear regression for the oil substitution time, the length of the bypass, and the flow speed. We determined an equation for calculating the length of the trailing oil contamination produced by the dead-leg. A modified equation for calculating the length of the contamination was obtained by combining the existing equation for calculating the length of the contamination with new factors based on our work. The amounts of contamination predicted by the new equation is closer to the actual contamination amounts than predicted values from other methods suggested by previous scholars.

scholarly journals Calculation method for the amount of contaminant oil during sequential transportation through product oil pipelines

2020 ◽  
Vol 38 (4) ◽  
pp. 1014-1033
Author(s):  
Enbin Liu ◽  
Wensheng Li ◽  
Hongjun Cai ◽  
Weibiao Qiao ◽  
Mohammadamin Azimi
Keyword(s):  
Cross Sections ◽  
Volume Fraction ◽  
Mixing Length ◽  
Refined Oil ◽  
Oil Pipeline ◽  
Actual Operation ◽  
Mixed Oil ◽  
The Relationship ◽  
Replacement Time

A considerable amount of oil contamination is caused by the presence of the trailing oil. This paper aims to simulate and analyze the influences of trailing oil on the quality of oil products in undulating sections. By studying the formation mechanism of mixed oil at inclining pipeline sections and the influences of velocity and oil batches on incline sections, as well as both ups and downs, the correlation is obtained between replacement time of different batches and velocity at various sections. By applying FLUENT 14.5, the maximum time of volume fraction of contaminant oil from 1% to 99% is simulated at cross-sections among different pipeline sections. Aiming at the relationship between oil product replacement time and change time of mixing section volume fraction and flow velocity, the mixing increment of undulating section relative to straight section is obtained. Combining with the empirical mixing length calculation equation, the equation for calculating mixing length considering terrain undulation is obtained. Combined with the actual operation data of Lan-Chengyu’s product oil pipeline, the error of the new mixed oil length calculation equation and actual oil mixing is 0.7966%. Excessive cutting amount of mixed oil will result in the waste of refined oil, and the less cutting amount will cause pollution of refined oil. The new mixed oil length calculation equation can more accurately guide the oil mixing cutting work at the oil station.

scholarly journals Research on Formation Mechanism of Trailing Oil in Product Oil Pipeline

2018 ◽  
Author(s):  
Enbin Liu ◽  
Wensheng Li ◽  
Hongjun Cai ◽  
Shanbi Peng
Keyword(s):  
Boundary Layer ◽  
Pipe Wall ◽  
Viscous Force ◽  
Refined Oil ◽  
Convection Diffusion ◽  
Oil Pipeline ◽  
Oil Transportation ◽  
The Dead ◽  
Modified Formula

Trailing oil is the tail section of contamination. There are two main reasons for the formation of trailing oil, one is the effect of laminar flow boundary layer, the other is the outflow of the preceding batch remained in the dead-legs. In the batch transportation of refined oil, under the action of viscous force, the preceding batch forms laminar boundary layer near the pipe wall and stays on the pipe wall, resulting in the phenomenon of contamination trailing and formation of trailing oil. When oil passes through the valve chamber of the oil transportation station, dead-leg will be formed. Due to gravity and convection diffusion, preceding batch flowing from dead-legs will form trailing oil in the pipeline. The phenomenon of trailing oil exists in the process of batch transportation, which will have an effect on the quality of oil. In this paper, Reynolds time-averaged method is used to simulate turbulence.Computational Fluid Dynamics(CFD) software is used to simulate different flow rates and bypass lengths to obtain contamination-related experimental data.Matlab software is used to perform multi-nonlinear regression for the oil substitution time, the length of the bypass and the flow rate. The formula for calculating the length of the trailing oil produced by the dead-leg is obtained. The modified formula for calculating the length of the contamination is obtained by combining the existing formula for calculating the length of the contamination.

scholarly journals Study on mixing interface of continuous large drop and U-shaped product pipeline

2021 ◽  
Vol 300 ◽  
pp. 01005
Author(s):  
Liang Feng ◽  
Huafeng Zhu ◽  
Junjiang Liu ◽  
Tianhao Liao
Keyword(s):  
Tracking Error ◽  
Diesel Oil ◽  
Previous Method ◽  
Mountainous Area ◽  
Large Drop ◽  
Long Distance ◽  
Oil Pipeline ◽  
Operation Control ◽  
Mixed Oil ◽  
Product Pipeline

In the long-distance pipeline of product oil, gasoline and diesel oil are transported in batches. Due to the large difference of physical properties between the two kinds of oil products, there will be oil mixing at each interface. Because the index parameters of mixed oil do not meet the sales standard, it is necessary to track the interface accurately, so as to provide necessary reference for cutting mixed oil. The topography of southwest mountainous area is characterized by continuous large drop and U-shape, which brings difficulties to batch tracking of product oil pipeline. The previous method is not suitable for this type of pipeline. Therefore, it is necessary to re study the batch tracking method of this type of product pipeline, and use vs2019 to write batch tracking software for continuous large drop and U-shaped product pipeline based on this method. The batch tracking error of the software for this type of pipeline is within the acceptable range, which can provide more accurate reference for the operation control personnel

‘Do you think you're at the Gresham?’: Accepting Imperfection in ‘The Dead’

2015 ◽  
Vol 10 (2) ◽  
pp. 159-177 ◽  
Author(s):  
Randi Saloman
Keyword(s):  
Sixteenth Century ◽  
Short Story ◽  
Secondary Quality ◽  
The Dead

Dublin's Gresham Hotel, where Gabriel and Gretta Conroy end their evening in Joyce's most famous short story, has a fascinating history. It was founded in 1817 by Thomas Gresham, who began life as a foundling rescued from the steps of London's Royal Exchange and was thereby given the name of the Renaissance statesman who built that exchange. This sixteenth-century Thomas Gresham was even better known, however, for his eponymous ‘Gresham's Law’. Both Gresham's Law and the hotel setting and history enter into and help to shape ‘The Dead’. Questions of value and valuing suggested by Gresham's Law are shown to be more complicated than they initially appear, as they intersect with the various forms of hospitality traced in the story. The ‘secondary’ quality of the famous Dublin hotel (built by the second, unknown Thomas Gresham) underscores – and ultimately redeems – the theme of secondariness that runs through ‘The Dead’.

Towards Predicting Relative Belt Edge Endurance With the Finite Element Method

1990 ◽  
Vol 18 (4) ◽  
pp. 216-235 ◽  
Author(s):  
J. De Eskinazi ◽  
K. Ishihara ◽  
H. Volk ◽  
T. C. Warholic
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Three Dimensional ◽  
The Finite Element Method ◽  
Shear Deformations ◽  
Element Analysis ◽  
Vertical Loading ◽  
Predicted Values ◽  
Element Method

Abstract The paper describes the intention of the authors to determine whether it is possible to predict relative belt edge endurance for radial passenger car tires using the finite element method. Three groups of tires with different belt edge configurations were tested on a fleet test in an attempt to validate predictions from the finite element results. A two-dimensional, axisymmetric finite element analysis was first used to determine if the results from such an analysis, with emphasis on the shear deformations between the belts, could be used to predict a relative ranking for belt edge endurance. It is shown that such an analysis can lead to erroneous conclusions. A three-dimensional analysis in which tires are modeled under free rotation and static vertical loading was performed next. This approach resulted in an improvement in the quality of the correlations. The differences in the predicted values of various stress analysis parameters for the three belt edge configurations are studied and their implication on predicting belt edge endurance is discussed.

Assessment of Pomegranate Juice as Antioxidant in Extender on Cauda Epididymis Spermatozoal Quality of Buck at Refrigerated Temperature

2019 ◽  
Vol 15 (02) ◽  
pp. 26-29
Author(s):  
Amarjeet Amarjeet ◽  
C T Khasatiya ◽  
L Chaudhary
Keyword(s):  
Detrimental Effect ◽  
Egg Yolk ◽  
Antioxidant Effect ◽  
Pomegranate Juice ◽  
Antioxidant Additive ◽  
Epididymal Spermatozoa ◽  
The Dead

The present investigation was carried out to study the refrigeration preservation of the cauda epididymal retrieved spermatozoa of buck in Tris egg yolk citrate (TEYC) dilutor containing pomegranate juice as antioxidant additive. The retrieved cauda epididymal spermatozoa extended in TEYC dilutor were studied in five groups by adding different concentration of pomegranate juice as additive (0% as control T1 group and 5%, 10%, 15% and 20% as treatment T2, T3, T4 and T5 groups, respectively) and storing at refrigerated temperature up to 48 hr. The results showed that the control extender had the least dead, abnormal and HOS non-reacted sperm percent among all treatments tested and that with increasing the pomegranate juice concentration in dilutor, the percentage of the dead, abnormal and HOST non-reacted spermatozoa increased significantly. The same trend was observed at all 12 hourly storage intervals indicating its detrimental effect on epididymal sperms of bucks at refrigeration temperature. The dead, abnormal, and HOST non-reacted sperm were significantly and positively interrelated with each other (r = 0.53-0.83). It was concluded that the inclusion of pomegranate juice in TEYC dilutor did not show any beneficial/antioxidant effect on epididymal sperms of buck in fresh or refrigerated semen and in fact all the levels of pomegranate juice (5% to 20%) were detrimental to cauda epididymal spermatozoa of a buck.

A Study on the Performance of Stratified Air Conditioning Design in Assembly Halls – A Case Study at the Dazhi Cultural Center in Taiwan

2013 ◽  
Vol 368-370 ◽  
pp. 599-602 ◽  
Author(s):  
Ian Hung ◽  
Hsien Te Lin ◽  
Yu Chung Wang
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Indoor Air ◽  
Air Conditioning ◽  
Cfd Simulation ◽  
Indoor Temperature ◽  
Cultural Center ◽  
Computational Fluid Dynamics Cfd

This study focuses on the performance of air conditioning design at the Dazhi Cultural Center and uses a computational fluid dynamics (CFD) simulation to discuss the differences in wind velocity and ambient indoor temperature between all-zone air conditioning design and stratified air conditioning design. The results have strong implications for air conditioning design and can improve the indoor air quality of assembly halls.

Influence of the speed of casting the dead head on the quality of tube steel

Metallurgist ◽  
1972 ◽  
Vol 16 (12) ◽  
pp. 863-864
Author(s):  
O. N. Suladze ◽  
Sh. D. Dzhaparidze ◽  
A. N. Lomashvili ◽  
Sh. P. Sakvarelidze ◽  
T. A. Tabidze
Keyword(s):  
Tube Steel ◽  
The Dead

scholarly journals An Examination of the Effects of Change in Committee Chair on Audit Quality

2017 ◽  
Vol 6 (4) ◽  
pp. 52
Author(s):  
Izhar Haq ◽  
Teresa Lang ◽  
Hongkang Xu
Keyword(s):  
Audit Committee ◽  
Audit Quality ◽  
Financial Statements ◽  
Discretionary Accruals ◽  
Committee Chair ◽  
The Absolute ◽  
Predicted Values ◽  
The Relationship ◽  
A Company

This study uses GMI Ratings directorship data from 2008 to 2013 along with the associated financial data to examine the relationship between audit committee chair change with the absolute discretionary accruals in the financial statements of the reporting companies.  Our results suggest that audit committee chair change is positively associated with the absolute discretionary accruals.  Specifically, absolute discretionary accruals are significantly higher when there is a change in the audit committee chair.  These results are consistent with prior research that deviations from the predicted values of accruals is an indicator of “poor” audit quality.  An additional finding of this paper is that a person younger than 60 is more likely to be a new audit committee chair when there is a change and therefore will have less experience and contacts than the outgoing chair. An important implication of these results is that audit committee chair change can have a significant impact on the quality of the financial statements of a company as well as on the audit quality.

scholarly journals Evaluation of the diesel engine feed by unified battlefield fuel F-34/F-35 mixed with biocomponents

2019 ◽  
Vol 178 (3) ◽  
pp. 240-246
Author(s):  
Mirosław KARCZEWSKI
Keyword(s):  
Diesel Engine ◽  
Ethyl Alcohol ◽  
Diesel Oil ◽  
Fuel System ◽  
Military Vehicles ◽  
Anhydrous Ethyl Alcohol ◽  
The Common ◽  
Fuel Mixtures ◽  
The Military

The problem of the military vehicles engines fuelling increases with the growth of the amount of vehicles in the armies. At the same time, another problem with fuel supply in modern engines is the use of bio component additives, which changes characteristics (quality) of the used fuels. Therefore, it is important to take actions to adapt engines to powering with fuels coming from renewable sources.The aim of the research was to evaluate the possibility of feeding the diesel engine (influence on the useful parameters and composi-tion) with mixtures of the unified battlefield fuel F-34/F-35 with biocomponents in the form of anhydrous ethyl alcohol and RME. The tests were conducted during fuelling of the engine with six kinds of fuels: basic fuel (diesel oil), NATO code F-34/F-35 fuel, as well as fuel mixtures: F-34 and RME with different ratio and F-34/F-35 with bioethanol. In the result of the research it was concluded that the parameters of the G9T Renault engine with the common rail fuel system in terms of F-34 and RME consumption (using) decreased in comparison to diesel oil basic fuel. It is not possible to supply the engine with the mixture of ethyl alcohol and F-34 fuel – alcohol pre-cipitation and obliteration of fuel system components

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