Parametric Study on Fluid Dynamics of Pilot-Control Angle Globe Valve

2018 ◽  
Vol 140 (11) ◽  
Author(s):  
Jin-yuan Qian ◽  
Zhi-xin Gao ◽  
Bu-zhan Liu ◽  
Zhi-jiang Jin
Keyword(s):  
Energy Consumption ◽  
Pressure Difference ◽  
Orifice Diameter ◽  
Piping System ◽  
Cross Sectional ◽  
Core Diameter ◽  
Large Orifice ◽  
Difference Calculation ◽  
Globe Valve ◽  
Pilot Valve

Globe valve is widely used in numerous industries, and its driving energy consumption accounts for high percentages of the whole piping system. In order to figure out novel globe valves with low energy consumption, the pilot control globe valve (PCGV) is proposed, which is made up of a main valve and a pilot valve. By the pressure difference of fluid itself, the opened/closed status of the main valve can be controlled by the pilot valve, which can save driving energy and shorten the response time. In order to fit PCGV in an angle displaced piping system, the pilot control angle globe valve (PCAGV) is developed. In this paper, with validated numerical methods, both steady and transient simulations focusing on the valve core diameter, the single/multi orifices, orifice diameters and their arrangements located on the valve core bottom are presented. The results show that the pressure difference increases with the increase of the valve core diameter and the decrease of the orifice diameter, and large orifice diameters (d > 12 mm) should be avoided in case the valve cannot be opened. As for the multi orifices, it can be treated as a single orifice which having similar cross-sectional area. Meanwhile, the opening time of the main valve also increases with the increase of the valve core diameter correspondingly. Besides, a fitting formula of pressure difference calculation depending on the inlet velocity and the valve core diameter is obtained, which is a power–law relationship.

Optimal Design Study on the Radian and Length of the Guide Plates for the Pipeline Elbow

2012 ◽  
Vol 426 ◽  
pp. 112-117
Author(s):  
Lan Ying Wu ◽  
Yan Lin Wang ◽  
Yong Wei
Keyword(s):  
Optimal Design ◽  
Pressure Difference ◽  
Total Pressure ◽  
Piping System ◽  
Cross Sectional ◽  
Obvious Effect ◽  
Structural Style ◽  
Guide Plate ◽  
Bending Radius ◽  
The Cross

Pipeline elbows are extensively applied in the liquid-conveying piping system, which vibration and noise control are always difficult and critical. The structural style of the guide plates for the liquid-conveying pipe noise eliminating elbow is numerical calculated in this paper, then we find that the fluid liquidity in the liquid-conveying pipe elbow is improved very well by the cross-sectional bending radian and export length of the guide plates, and the two parameters are also optimal designed. The calculated results show that the total pressure difference in the liquid-conveying pipeline elbow decreases first and then increases with the cross-sectional bending radius of the guide plate increases; The total pressure difference decreases first and then increases with the export length of the guide plate increases; When the guide plates according to the gold ratio arrangement, the number, the cross-sectional bending radius and the length are 2, 200 mm and 40 mm respectively, we obtain the total pressure difference is 10707.87 Pa in the liquid-conveying pipeline elbow, comparing it to the result of the original program, it decreases 38.58%, so the internal flow field is improved better, the optimal design has a very obvious effect.

Numerical Study on Pressure Difference of Valve Core in Vertical Pilot-Control Globe Valve

2017 ◽  
Author(s):  
Zhi-xin Gao ◽  
Fu-qiang Chen ◽  
Jin-yuan Qian ◽  
Zhi-jiang Jin
Keyword(s):  
Pressure Difference ◽  
Numerical Study ◽  
Orifice Diameter ◽  
Inlet Velocity ◽  
Before And After ◽  
Computational Fluid Dynamics Cfd ◽  
Cfd Method ◽  
Globe Valve ◽  
Opening And Closing ◽  
Core Displacement

Vertical pilot-control globe valve (VPCGV) is a novel globe valve that costs little driving energy and responds quickly. In VPCGV, the opening and closing forces are related to the pressure difference before and after the valve core. In this paper, parameters that have influences on pressure difference such as orifice diameter, valve core displacement, and inlet velocity are thoroughly investigated by computational fluid dynamics (CFD) method. It is found that pressure difference increases with the raising of inlet velocity and the diminishing of valve core displacement, and middle-sized orifice diameter is the best in VPCGV. Furthermore, the correlation between pressure difference and inlet velocity is obtained, which can be beneficial for the selection of VPCGV under certain conditions.

Computational fluid dynamics analysis on orifice structure inside valve core of pilot-control angle globe valve

2017 ◽  
Vol 232 (13) ◽  
pp. 2419-2429 ◽  
Author(s):  
Zhi-Jiang Jin ◽  
Zhi-Xin Gao ◽  
Ming Zhang ◽  
Bu-Zhan Liu ◽  
Jin-Yuan Qian
Keyword(s):  
Orifice Diameter ◽  
Piping System ◽  
Process Industries ◽  
Inlet Velocity ◽  
Computational Fluid Dynamics Analysis ◽  
Loss Coefficients ◽  
Globe Valve ◽  
Opening And Closing ◽  
Core Displacement ◽  
Addition Formulas

A novel pilot-control angle globe valve is proposed, and it has an obvious advantage of energy conservation during its opening and closing process. In pilot-control angle globe valve, the opening and closing forces are related to the orifice located inside the valve core. In this paper, the effects of orifice diameter are thoroughly studied under different working conditions such as valve core displacements and inlet velocities. To begin with, the numerical model is validated by comparing similar angle valves, and then the flow and loss coefficients under different orifice diameters are discussed. It is found that the effects of orifice diameter on force acting on valve core depend on valve core displacement and inlet velocity. Thus different valve core displacements and inlet velocities combined with different orifice diameters are further studied. It is also found that when the orifice diameter is larger than 12 mm, pilot-control angle globe valve cannot be used under small inlet velocity or large valve core displacement. In addition, formulas to calculate forces on valve core are proposed for further orifice design. This work can be referred in process industries especially in a piping system with orifice plates or globe valves.

INTERARM SYSTOLIC BLOOD PRESSURE DIFFERENCE IS ASSOCIATED WITH A HIGH PREVALENCE OF CARDIO VASCULAR DISEASES- A CROSS-SECTIONAL STUDY IN POLICE WORKER

2020 ◽  
Vol 4 (11) ◽  
Author(s):  
Somesh Raju ◽  
Rina Kumari ◽  
Sunita Tiwari ◽  
NS Verma
Keyword(s):  
Blood Pressure ◽  
Systolic Blood Pressure ◽  
Blood Sugar ◽  
Pressure Difference ◽  
Systolic Pressure ◽  
Working Environment ◽  
Vascular Events ◽  
Cross Sectional ◽  
Blood Pressure Difference ◽  
High Prevalence

Background: Interarm systolic blood pressure difference more than 10 mm of Hg is predictor of cardiovascular and metabolic risk. Despite of sufficient physical activity there is high prevalence of obesity in police personal because of stressful working environment. No studies have addressed the significance of interarm pressure difference among them. Therefore, the present study conducted to access the relation of interarm blood pressure difference with obesity in police personnel. Aims and Objective: To estimate the interarm pressure difference in police personal to see its association with their obesity. Material and Method: This cross-sectional observational study done on 245 police workers in PAC, Sitapur, India. Subjects having more than ten years of working experience were included in study. Anthropometric measurements of subject recorded by following standard protocol. Measurement of systolic pressure in both arm recorded simultaneously by mercury sphygmomanometer. Available data analyze and expressed in percentage, mean with SD and chi square test to see the significance of association. Results: According to anthropometric results of subjects 77.14 prcent subjects were having generalised obesity and 82.04 percent of subjects having abdominal obesity. 34.29 percent of subjects showed abnormally high (?10 mmHg) inter-arm systolic blood pressure difference. Both type of obesity showed positive association with blood sugar level but no association with interarm pressure difference. Conclusion: Interarm blood pressure difference is greater in individual having obesity or prolong duration of service. Such subjects are more susceptible to develop coronary artery disease or peripheral arterial disease in future. Early screening can help to detect the vascular events likely to occur in the future Keywords: Body mass index, Waist circumference, Interarm pressure difference, Random blood sugar

scholarly journals Associations between Fasting Duration, Timing of First and Last Meal, and Cardiometabolic Endpoints in the National Health and Nutrition Examination Survey

Nutrients ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 2686
Author(s):  
Michael D. Wirth ◽  
Longgang Zhao ◽  
Gabrielle M. Turner-McGrievy ◽  
Andrew Ortaglia
Keyword(s):  
Energy Consumption ◽  
National Health ◽  
Survey Design ◽  
Glycosylated Hemoglobin ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Nutrition Examination Survey ◽  
Cross Sectional ◽  
Health And Nutrition ◽  
Fasting Duration

Background: Research indicates potential cardiometabolic benefits of energy consumption earlier in the day. This study examined the association between fasting duration, timing of first and last meals, and cardiometabolic endpoints using data from the National Health and Nutrition Examination Survey (NHANES). Methods: Cross-sectional data from NHANES (2005–2016) were utilized. Diet was obtained from one to two 24-h dietary recalls to characterize nighttime fasting duration and timing of first and last meal. Blood samples were obtained for characterization of C-reactive protein (CRP); glycosylated hemoglobin (HbA1c %); insulin; glucose; and high-density lipoprotein (HDL), low-density lipoprotein (LDL), and total cholesterol. Survey design procedures for adjusted linear and logistic regression were performed. Results: Every one-hour increase in nighttime fasting duration was associated with a significantly higher insulin and CRP, and lower HDL. Every one-hour increase in timing of the last meal of the day was statistically significantly associated with higher HbA1c and lower LDL. Every one-hour increase in first mealtime was associated with higher CRP (β = 0.044, p = 0.0106), insulin (β = 0.429, p < 0.01), and glucose (β = 0.662, p < 0.01), and lower HDL (β = −0.377, p < 0.01). Conclusion: In this large public health dataset, evidence for the beneficial effect of starting energy consumption earlier in the day on cardiometabolic endpoints was observed.

Dietary intake among under-, normal- and overweight 9- and 15-year-old Estonian and Swedish schoolchildren

2007 ◽  
Vol 10 (3) ◽  
pp. 311-322 ◽  
Author(s):  
Inga Villa ◽  
Agneta Yngve ◽  
Eric Poortvliet ◽  
Andrej Grjibovski ◽  
Krystiine Liiv ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Dietary Intake ◽  
Dietary Habits ◽  
Age Groups ◽  
Meat Products ◽  
Food Group ◽  
Biological Factors ◽  
Cross Sectional ◽  
Total Food ◽  
Country Specific

AbstractObjectivesTo determine the differences in macronutrient and food group contribution to total food and energy intakes between Estonian and Swedish under-, normal- and overweight schoolchildren, and to estimate the association between diet and body mass index (BMI).DesignCross-sectional comparison between Estonian and Swedish children and adolescents of different BMI groups.SettingTwenty-five schools from one region in Estonia and 42 in two regions of central Sweden.SubjectsIn total 2308 participants (1176 from Estonia and 1132 from Sweden), including 1141 children with a mean age of 9.6 ± 0.5 years and 1167 adolescents with a mean age of 15.5 ± 0.6 years.ResultsOverweight was more prevalent among younger girls in Sweden (17.0 vs. 8.9%) and underweight among girls of both age groups in Estonia (7.9 vs. 3.5% in younger and 10.5 vs. 5.1% in older age group of girls). Compared with that of normal- and underweight peers, the diet of overweight Estonian children contained more energy as fat (36.8 vs. 31.7%) but less as carbohydrates, and they consumed more milk and meat products. Absolute BMI of Estonian participants was associated positively with energy consumption from eggs and negatively with energy consumption from sweets and sugar. Swedish overweight adolescents tended to consume more energy from protein and milk products. Risk of being overweight was positively associated with total energy intake and energy from fish or meat products. In both countries the association of overweight and biological factors (pubertal maturation, parental BMI) was stronger than with diet.ConclusionThe finding that differences in dietary intake between under-, normal- and overweight schoolchildren are country-specific suggests that local dietary habits should be considered in intervention projects addressing overweight.

Effects of Sleeve Parameters On Cavitation Control Performance in Steam Trap Valves

2021 ◽  
Author(s):  
Chang Qiu ◽  
Zhi-xin Gao ◽  
Zhi-jiang Jin ◽  
Jin-yuan Qian
Keyword(s):  
Power Systems ◽  
Optimization Design ◽  
Thermal Power ◽  
Orifice Diameter ◽  
Geometrical Parameters ◽  
Piping System ◽  
Cavitation Performance ◽  
Installation Angle ◽  
Steam Trap ◽  
Cavitation Intensity

Abstract The steam trap valve is used in thermal power systems to pour out condensate water and keep steam inside. While flowing through steam trap valves, the condensate water can easily reach cavitation, which may cause serious damage to the piping system. In this paper, in order to control cavitation inside steam trap valves, effects of sleeve parameters, including orifice diameter, installation angle and thickness, are investigated using a cavitation model. The pressure, velocity and vapor distribution inside valves are analyzed and compared for different sleeve geometrical parameters. The total vapor volumes are also predicted and compared. The results show that the sleeve parameters have a significant influence on the cavitation intensity and cavitation vapor distributions. Specifically, the orifice diameter of the sleeve has much larger effect on each aspect than that of other two geometrical parameters of the sleeve. The improved geometrical parameters of the sleeve are determined to suppress the cavitation inside the valve. The sleeve with smaller diameter orifices, higher installation angle (maximum 80°) and higher thickness is recommended in practice for better anti-cavitation performance. The work is of significance for cavitation control and the optimization design of steam trap valves.

Economic globalization and energy consumption patterns in Organisation for Economic Co-operation and Development economies

2021 ◽  
pp. 0958305X2110425
Author(s):  
Hemachandra Padhan ◽  
Santosh Kumar Sahu ◽  
Umakant Dash
Keyword(s):  
Energy Consumption ◽  
Economic Globalization ◽  
Consumption Patterns ◽  
Coal Consumption ◽  
Cross Sectional ◽  
Important Indicator ◽  
Distributed Lag ◽  
Long Run ◽  
Energy Consumption Patterns ◽  
The Impact

This study examines the impact of economic globalization on the patterns of energy consumption for 24 Organisation for Economic Co-operation and Development (OECD) economies from 1995 to 2015. We employ Westerlund cointegration, which shows a long-run association between economic globalization and energy consumption patterns. Furthermore, cross-sectional autoregressive distributed lag models (CS-ARDL) results explain the short-run and long-run relationship between the series. The results further explain that economic globalization reduces oil and coal consumption while accelerating gas consumption in OECD economies. We additionally employ the Eberhardt augmented mean group test to verify consistency with CS-ARDL results. The empirical evidence of this study suggests that OECD economies’ policymakers should prioritize economic globalization in framing policies related to energy consumption. Furthermore, allocating funds for better technology related to high polluting fuels should be one of the crucial considerations arising from this study. Finally, we recommend economic globalization as an important indicator to address the issues related to OECD economics’ environmental and ecological footprints.

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