Controlling Surge Due to Shut-Off Fast Closing Valve at the End of an Oil Pipeline

2006 ◽  
Author(s):  
Wei Wang ◽  
Jing Gong
Keyword(s):  
Control Measures ◽  
Maximum Pressure ◽  
Operating Parameters ◽  
Valve Closure ◽  
Oil Pipeline ◽  
Closure Time ◽  
Pump Station ◽  
Surge Control ◽  
Relief System ◽  
Product Pipeline

Surge will be induced in oil transfer pipeline, due to the changes of transportation materials, operating parameters or pump station equipments. However, the surge induced by Shut-off fast closing valve could be more destructive, for the duration of valve closure time is short, and then the maximum pressure of the surge is much higher, so it’s necessary to control the surge. Based on the characteristic method, this paper establishes a numerical calculation of the accidental Shut-off the terminal fast closing valve at an product pipeline, and simulates the corresponding transient process of pipeline pressure. Upon the upper result, a further research, which combines the boundary condition of surge relief system, is carried out, in order to get the optimal surge control measures through the relief system.

Charts for water hammer in pipelines resulting from valve closure from full opening only

1985 ◽  
Vol 12 (2) ◽  
pp. 241-264 ◽  
Author(s):  
Bryan W. Karney ◽  
Eugen Ruus
Keyword(s):  
Good Accuracy ◽  
Pipe Wall ◽  
Pressure Head ◽  
Wall Friction ◽  
Maximum Pressure ◽  
Valve Closure ◽  
Closure Time ◽  
Basic Parameters ◽  
Valve Opening ◽  
Open Position

Maximum pressure head rises, which result from total closure of the valve from an initially fully open position, are calculated and plotted for the valve end and for the midpoint of a simple pipeline. Uniform, equal-percentage, optimum, and parabolic closure arrangements are analysed. Basic parameters such as pipeline constant, relative closure time, and pipe wall friction are considered with closures from full valve opening only. The results of this paper can be used to draw the maximum hydraulic grade line along the pipe with good accuracy for the closure arrangements considered. It is found that the equal-percentage closure arrangement yields consistently less pressure head rise than does the parabolic closure arrangement. Further, the optimum closure arrangement yields consistently less head rise than the equal-percentage one. Uniform closure produces pressure head rise that usually lies between those produced by the parabolic and the equal-percentage closure arrangements, except for the range of low pressure head rise combined with low or zero friction, where the rise due to uniform closure approaches that produced by optimum closure.

Charts for water hammer in pipelines resulting from valve closure

1980 ◽  
Vol 7 (2) ◽  
pp. 243-255 ◽  
Author(s):  
Eugen Ruus ◽  
Farouk A. El-Fitiany
Keyword(s):  
Pipe Wall ◽  
Pressure Head ◽  
Water Hammer ◽  
Wall Friction ◽  
Maximum Pressure ◽  
Valve Closure ◽  
Closure Time ◽  
Basic Parameters

Maximum pressure head rises, which result from valve closure according to (a) uniform, (b) equal-percentage, and (c) optimum valve closure arrangements, are calculated and plotted for the valve end and for the midpoint of a simple pipeline. Basic parameters such as the pipeline constant, relative closure time, and pipe wall friction are considered for closures both from partial as well as from full valve openings. The results of this paper can be used to draw the maximum hydraulic grade line along the pipe for these closure arrangements. It is found that the equal-percentage closure arrangement yields consistently less pressure head rise than does the uniform closure arrangement. Further, the optimum closure arrangement yields consistently less head rise than the equal-percentage one. Closures from partial valve openings increase the pressure head rise considerably and must always be considered.

Simulation of Liquid-Gas Replacement in Commissioning Process for Large-Slope Crude Oil Pipeline

2012 ◽  
Author(s):  
Yuanyuan Chen ◽  
Jing Gong ◽  
Xiaoping Li ◽  
Nan Zhang ◽  
Shaojun He ◽  
...  
Keyword(s):  
Crude Oil ◽  
Flow Rate ◽  
Liquid Flow ◽  
Liquid Flow Rate ◽  
Fluid Model ◽  
Engineering Application ◽  
Computational Procedure ◽  
Control Measures ◽  
Production Operation ◽  
Oil Pipeline

Pipeline commissioning, which is a key link from engineering construction to production operation, is aim to fill an empty pipe by injecting water or oil to push air out of it. For a large-slope crude oil pipeline with great elevation differences, air is fairly easy to entrap at downward inclined parts. The entrapped air, which is also called air pocket, will cause considerable damage on pumps and pipes. The presence of it may also bring difficulties in tracking the location of the liquid head or the interface between oil and water. It is the accumulated air that needed to be exhausted in time during commissioning. This paper focuses on the simulation of liquid-gas replacement in commissioning process that only liquid flow rate exists while gas stays stagnant in the pipe and is demanded to be replaced by liquid. Few previous researches have been found yet in this area. Consequently, the flow in a V-section pipeline consisted of a downhill segment and a subsequent uphill one is used here for studying both the formation and exhaustion behaviors of the intake air. The existing two-fluid model and simplified non-pressure wave model for gas-liquid stratified flow are applied to performance the gas formation and accumulation. The exhausting process is deemed to be a period in which the elongated bubble (Taylor bubble) is fragmented into dispersed small bubbles. A mathematical model to account for gas entrainment into liquid slug is proposed, implemented and incorporated in a computational procedure. By taking into account the comprehensive effects of liquid flow rate, fluid properties, surface tension, and inclination angle, the characteristics of the air section such as the length, pressure and mass can be calculated accurately. The model was found to show satisfactory predictions when tested in a pipeline. The simulation studies can provide theoretical support and guidance for field engineering application, which are meanwhile capable of helping detect changes in parameters of gas section. Thus corresponding control measures can be adopted timely and appropriately in commissioning process.

Abstract 1606: High Specificity of Prolonged Isovolumic Contraction Time for Reverse Remodeling Associated with Cardiac Resynchronization Therapy

Circulation ◽  
2007 ◽  
Vol 116 (suppl_16) ◽  
Author(s):  
Chinami Miyazaki ◽  
Charles J Bruce ◽  
Margaret M Redfield ◽  
Raul E Espinosa ◽  
David L Hayes ◽  
...  
Keyword(s):  
Mitral Valve ◽  
Cardiac Resynchronization Therapy ◽  
Roc Analysis ◽  
High Specificity ◽  
Cardiac Resynchronization ◽  
Reverse Remodeling ◽  
Contraction Time ◽  
Valve Closure ◽  
Resynchronization Therapy ◽  
Closure Time

Background: Isovolumic contraction time (ICT) and pre-ejection period (PEP) are altered by electrical conduction delay as well as impaired contractility. An abnormal PEP has been used to select patients for cardiac resynchronization therapy (CRT), however, the predictive value of PEP for reverse remodeling (RR) has not been reported. The purpose of this study is to determine the predictive value of ICT and PEP for the RR in a prospective, single center CRT registry. Methods: Prospective registry of all heart failure patients undergoing CRT with echo pre-implant and at 3 and 6 months after implant. PEP was measured from the ECG Q wave onset to the aortic valve opening from the left ventricular outflow tract pulsed-wave Doppler tracing. The timing interval from the QRS onset to mitral valve closure was measured (mitral valve closure time). ICT was calculated as PEP-mitral valve closure time. RR was defined as >15% reduction in end-systolic volume (ESV) measured by biplane Simpson’s method. Death due to cardiac cause and heart transplantation during the 6 month period were considered as a non-response in the receiver-operating characteristics (ROC)analysis. Results: Echocardiography data was available in 83 patients at 3 and 59 patients at 6 month after CRT. RR occurred in 42 patients (51%) at 3 months and in 32 (54%) patients at 6 months By ROC analysis, the area under the curve (AUC) for predicting RR was 0.74 for ICT (p<0.001) and 0.73 for PEP (p=0.001) (See table ). ICT>123 ms yielded a very high specificity of 90–93% to predict responders at 6 month after CRT either in entire population or after excluding the patients with atrial fibrillation. Conclusion: A prolonged ICT is highly specific for predicting reverse remodeling after CRT although it is found in a limited number of patients. A strategy employing a screening ICT measurement may identify patients highly likely to achieve reverse remodeling after CRT, but can not be used to exclude patients for CRT. ROC analysis

scholarly journals Experimental and Numerical Characterization of the Sliding Rotary Vane Expander Intake Pressure in Order to Develop a Novel Control-Diagnostic Procedure

Energies ◽  
2019 ◽  
Vol 12 (10) ◽  
pp. 1970 ◽  
Author(s):  
Fabio Fatigati ◽  
Marco Di Bartolomeo ◽  
Davide Di Battista ◽  
Roberto Cipollone
Keyword(s):  
Waste Heat ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Maximum Pressure ◽  
Operating Parameters ◽  
Road Transportation ◽  
The Road ◽  
Numerical Characterization ◽  
On The Road ◽  
Intake Pressure

Waste heat recovery via Organic Rankine Cycle (ORC)-based power units represents one of the most promising solutions to counteract the effects of CO2 emissions on climate change. Nevertheless, several aspects are still limiting its development on the on-the-road transportation sector. Among these aspects, the significant variations of the conditions of the hot source (exhaust gases) are a crucial point. Therefore, the components of the ORC-based unit operate far from the design point if the main operating parameters of the plant are not suitably controlled. The maximum pressure of the cycle is one of the most important variables to be controlled for the importance it has on the effectiveness of the recovery and on safety of operation. In this paper, a wide experimental and theoretical activity was performed in order to define the operating parameters that mostly affect the maximum pressure of the recovery unit. The results showed that the mass flow rate provided by the pump and the expander volumetric efficiency were the main drivers that affect the plant maximum pressure. Subsequently, through a validated model of the expander, a diagnostic map was outlined to evaluate if the expander and, consequently, the whole plant were properly working.

Maximum Pressure Head Due to Linear Valve Closure

1991 ◽  
Vol 113 (4) ◽  
pp. 643-647 ◽  
Author(s):  
Chyr Pyng Liou
Keyword(s):  
Flow Characteristic ◽  
Pressure Head ◽  
Head Loss ◽  
Water Hammer ◽  
Point Of View ◽  
Global Perspective ◽  
Maximum Pressure ◽  
Valve Closure ◽  
Subtle Effect ◽  
Dimensionless Variables

The maximum pressure head resulting from one-speed closure of wide open valves is investigated. The dimensionless variables formulated in this study make the subtle effect of the initial valve head loss explicit and separate from that of the pipe frictional head loss. The maximum head is related to initial pipe frictional head loss, the initial valve head loss, the inherent flow characteristic of the valve, and the closure period by plots of dimensionless variables. The trends of the variation of the maximum pressure head are discussed. An example is used to illustrate the usage of the plots, and to show the advantage of having a global perspective of the phenomenon in the selection and sizing of valves from the water hammer point of view.

Comparisons of CFD and Traditional Solutions for Steam Hammer Events

2017 ◽  
Author(s):  
Alex Mayes ◽  
Kshitij P. Gawande ◽  
Dennis K. Williams
Keyword(s):  
Pressure Wave ◽  
Power Plants ◽  
Peak Load ◽  
Critical Length ◽  
Pressure Change ◽  
Piping System ◽  
Valve Closure ◽  
Pipe System ◽  
Closure Time ◽  
Pressure Changes

Sudden pressure changes in the piping system of power plants are inevitable, and thus potential serious damage to large components, piping system, and piping supports is possible. To protect valuable components from such events, abrupt valve closure is employed to restrict the flow and prevent significant incidents and the resulting plant downtime. Unfortunately, when a valve is suddenly closed to prevent damage caused by unexpected events, a pressure wave within the flow is created, which travels upstream and impacts at the pipeline elbows. These events, involving sudden changes in pressure, are known as steam hammer. This steam hammer pressure wave, traveling through the pipe system, is capable of producing significant transient loads and stresses, which can disrupt the piping supports. As such there is a need for further investigation. The pressure wave depends on the characteristics of the flow, valve closure time, the elbow-to-elbow pipe section lengths, and the piping system flexibility. The present study performs a CFD analysis of the fluid experiencing such a sudden pressure change. OpenFOAM is used for this analysis and considers all the flow parameters, valve closure time, and critical length of the straight pipe. The study intends to provide a means of calculating the transient steam hammer loads applied on the pipe elbows, which consequently allows appropriate pipe support selection based upon the resulting peak loads. This computational analysis is compared to analytical methods for peak load determination such as rigid column theory, the Joukowsky method, and the steam hammer method explained by Coccio (1967) and Goodling (1989).

Effect of valve closure time on the determination of respiratory resistance by flow interruption

1987 ◽  
Vol 25 (2) ◽  
pp. 136-140 ◽  
Author(s):  
J. H. T. Bates ◽  
I. W. Hunter ◽  
P. D. Sly ◽  
S. Okubo ◽  
S. Filiatrault ◽  
...  
Keyword(s):  
Valve Closure ◽  
Respiratory Resistance ◽  
Flow Interruption ◽  
Closure Time

Third-Party Damage Factors Analysis and Control Measures of Daqing-Harbin Oil Pipeline

2013 ◽  
Vol 411-414 ◽  
pp. 2527-2532 ◽  
Author(s):  
Li Xin Wei ◽  
Li Yan Han
Keyword(s):  
Fault Tree ◽  
Control Measures ◽  
Third Party ◽  
Tree Model ◽  
Legal Concept ◽  
Oil Pipeline ◽  
The Third ◽  
Pipeline Failure ◽  
Main Factors ◽  
The Third Party

The third-party damage is the main factor of Daqing-Harbin oil pipeline failure. This paper analyzes a variety of factors causing the third-party damage, and establishes the fault tree model. By analyzing the minimal cut set and structures importance degree of fault tree, the main factors of the third-party damage that caused pipeline failure are determined. The main factors are as follows: Lack of pipeline conditions, human vandalism, the frequency of line patrol and management systems, lack of public education and the legal concept, and construction operation injury. On the basis of analyzing the factors, the precautions of the third-party interference are proposed.

Simulation of Operation Scheme of Su Cuo Buried Oil Pipeline

2011 ◽  
Vol 356-360 ◽  
pp. 3023-3027
Author(s):  
Li Xin Wei ◽  
Lu Ying Zhang ◽  
Yu Wang
Keyword(s):  
Simulation Model ◽  
Simulation Software ◽  
Operating Conditions ◽  
Operating Parameters ◽  
Saving Energy ◽  
Operating Condition ◽  
Oil Pipeline ◽  
Actual Operating ◽  
Different Seasons

Aim at the actual operating condition of Su Cuo buried oil pipeline, the simulation model of this pipeline operation was built by the simulation software of TLNET to simulate the running states of pipeline in different operating conditions. With the target of saving energy and reducing consumption, the operating parameters of this pipeline with different throughput and different seasons were optimized, and the optimization results can be used to guide the pipeline operation.

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