BEHAVIOR OF WATER-FLOWED PIPES AT DIFFERENT TEMPERATURES

2020 ◽  
Vol 2 (3) ◽  
pp. 51-69
Author(s):  
António Vilela Gomes
Keyword(s):  
Numerical Study ◽  
Linear Thermal Expansion ◽  
Correct Choice ◽  
Galvanized Steel ◽  
Head Losses ◽  
Technological Advances ◽  
Piping Systems ◽  
Different Temperatures ◽  
Hydraulic Networks ◽  
Fluid Losses

Abstract The implementation of water piping systems shows significant technological advances in the specialty of hydraulics. The pipes have great advantages, namely, in the reduction of fluid losses, as well as in the mitigation of problems resulting from water interruption and its preservation in relation to external harmful agents. In this numerical study will be tested pipes of various materials such as cast iron, stainless steel, galvanized steel, pex and fiberglass. The fluid that will circulate inside is water at different temperatures. Subsequently, several parameters will be evaluated, such as the friction factor, the head losses, the linear thermal expansion and the stress in the piping. Knowledge of these factors is paramount for the correct sizing of hydraulic networks, as well as for the correct choice of pumping systems.

Numerical study of asymmetric and axisymmetric thermal jet with entropy generation concept

2021 ◽  
Vol 15 (1) ◽  
pp. 7628-7636
Author(s):  
D. Belakhal ◽  
Kouider Rahmani ◽  
Amel Elkaroui Elkaroui ◽  
Syrine Ben Haj Ayech ◽  
Nejla Mahjoub Saïd ◽  
...  
Keyword(s):  
Entropy Generation ◽  
Numerical Study ◽  
Experimental Studies ◽  
Three Dimensional ◽  
Variable Density ◽  
Current Investigation ◽  
Numerical Resolution ◽  
Different Temperatures ◽  
Density Ratios ◽  
The Impact

In the current investigation, numerical study of a thermal jet of asymmetric (rectangular and elliptical) and axisymmetric (circular) geometry was investigated with variable density to verify the impact of the ratio of density and geometry on the generation of entropy. The central jet was brought to different temperatures (194, 293 and 2110 K) to obtain density ratios (0.66, 1 and 7.2) identical to a mixture jet ((Air-CO2), (Air-Air) and (Air-He)), respectively. Solving the three-dimensional numerical resolution of the Navier Stocks for turbulent flow permanent enclosed on the turbulence model K-εstandard was made. The results acquired are compared with that carried out in previous experimental studies, where it was concluded that, the axisymmetric (circular) geometry increases the entropy generation.

Study on High-Temperature Creep Behavior of T23 and T24 Steels

2018 ◽  
Vol 789 ◽  
pp. 182-186
Author(s):  
Jin Ping Pan ◽  
Shu Heng Tu ◽  
Ding Jun Chu ◽  
Xin Wei Zhu ◽  
Bin Hu ◽  
...  
Keyword(s):  
High Temperature ◽  
Creep Behavior ◽  
Rupture Strength ◽  
Progressive Increase ◽  
High Temperature Creep ◽  
Creep Tests ◽  
Theoretical Simulation ◽  
Temperature Creep ◽  
Piping Systems ◽  
Different Temperatures

A progressive increase of plant efficiency calls for new requirements of heat-resistantsteels used in the boiler and piping systems. In this paper, high-temperature creep behavior of T23and T24 steels were studied. Creep tests over a long period of time have been conducted for bothsteels at different temperatures. The creep mechanisms of the two steels have been clarified byanalyzing the minimum creep rate versus stress data. Besides, the creep rupture data from the creeptests were in good accordance with theoretical simulation on the basis of the CDM model over a longtime. Creep temperature has great effects on the rupture strength of the two steels. By creep ruptureexperiments and appropriate modelling, the high-temperature creep behavior can be well described.

scholarly journals NUMERICAL STUDY ON THE INHIBITION OF CAVITATION IN PIPING SYSTEMS

2012 ◽  
Vol 19 ◽  
pp. 374-380
Author(s):  
SUN SEOK BYEON ◽  
SANG JUN LEE ◽  
YOUN-JEA KIM
Keyword(s):  
Vapor Pressure ◽  
Volume Fraction ◽  
Numerical Study ◽  
Fluid Velocity ◽  
Working Fluid ◽  
Operating Pressure ◽  
Butterfly Valve ◽  
Saturation Vapor Pressure ◽  
Piping Systems ◽  
Saturation Vapor

Abrupt closing valve in piping systems is sometimes resulted in cavitation due to the occurrence of high pressure difference. The bubbles generating by cavitation influence operating pressure and then those generate shock wave and vibration. These phenomena can consequentially cause to corrosion and erosion. So, the cavitation is the important factor to consider reliability of piping systems and mechanical lifetime. This paper investigated the various inhibition methods of cavitation in piping systems in which butterfly valves are installed. To prevent cavitation occurrence, it is desirable to analyze its characteristics between the upstream and downstream of process valve. Results show that the fluid velocity is fast when a working fluid passed through butterfly valve. The pressure of these areas was not only under saturation vapor pressure of water, but also cavitation was continuously occurred. We confirmed that the effect of existence of inserted orifice and influence to break condition under saturation vapor pressure of water. Results were graphically depicted by pressure distribution, velocity distribution, and vapor volume fraction.

Confirmation of the new technique for measuring the linear thermal expansion of silicon

1993 ◽  
Vol 8 (1) ◽  
pp. 36-38 ◽  
Author(s):  
Liu Fengchao
Keyword(s):  
Thermal Expansion ◽  
Room Temperature ◽  
Accurate Determination ◽  
Linear Thermal Expansion ◽  
Linear Expansion Coefficient ◽  
X Ray ◽  
High Purity Silicon ◽  
Different Temperatures ◽  
Better Than

This paper further confirms that the direct measurement of diffraction angles at different temperatures by using the X-ray diffractometer is better than measurement of the lattice parameters for the rapid and accurate determination of the linear thermal expansion of silicon. High purity silicon has the linear expansion coefficient, α= (2.45±0.05) × 10−6/°C at room temperature. This value does not change for doped P-type and N-type silicon.

Experimental and Numerical Study on Dynamic Properties of Viscoelastic Microvibration Damper Considering Temperature and Frequency Effects

2016 ◽  
Vol 11 (6) ◽  
Author(s):  
Chao Xu ◽  
Zhao-Dong Xu ◽  
Teng Ge ◽  
Ya-Xin Liao
Keyword(s):  
Loss Factor ◽  
Numerical Study ◽  
Dynamic Properties ◽  
Frequency Effect ◽  
Solid Model ◽  
Temperature Dependent ◽  
Frequency Effects ◽  
Proposed Model ◽  
Different Temperatures ◽  
Increasing Temperature

This work presents an experimental and numerical study on the dynamic properties of viscoelastic (VE) microvibration damper under microvibration conditions at different frequencies and temperatures. The experimental results show that the storage modulus and the loss factor of VE microvibration damper both increase with increasing frequency but decrease with increasing temperature. To explicitly and accurately represent the temperature and frequency effects on the dynamic properties of VE microvibration damper, a modified standard solid model based on a phenomenological model and chain network model is proposed. A Gaussian chain spring and a temperature-dependent dashpot are employed to reflect the temperature effect in the model, and the frequency effect is considered with the nature of the standard solid model. Then, the proposed model is verified by comparing the numerical results with the experimental data. The results show that the proposed model can accurately describe the dynamic properties of VE microvibration damper at different temperatures and frequencies.

Experimental and Numerical Study on Cooling Process of Sinter

2013 ◽  
Vol 816-817 ◽  
pp. 216-220
Author(s):  
Lian Lian Guo ◽  
Jing Fu Wang ◽  
Yin Zhi Wang
Keyword(s):  
Specific Heat ◽  
Air Temperature ◽  
Initial Temperature ◽  
Numerical Study ◽  
Actual Condition ◽  
Cooling Process ◽  
Heat Utilization ◽  
Exhaust Heat ◽  
Different Temperatures ◽  
Porous Medium Model

By means of thermal analysis, specific heat values of sinter with different temperatures are measured and the linear function which along with the change of temperature is got. According to the actual condition, the porous medium model which describes the cooling process is established. The influences on cooling process of specific heat with fixed and variational values are compared. With the variational specific heat, the effects on cooling process of sinter initial temperature and air temperature are discussed. The result shows that both increasing sinter initial temperature and cold air temperature can improve the exhaust heat utilization, but the later delay the cooling time.

Experimental investigation and constitutive modelling of the deformation behaviour of high impact polystyrene for plug-assisted thermoforming

2020 ◽  
Vol 21 (6) ◽  
pp. 607
Author(s):  
Oualid Atmani ◽  
Fazilay Abbès ◽  
Yuming Li ◽  
Serge Batkam ◽  
Boussad Abbès
Keyword(s):  
Numerical Study ◽  
Deformation Behaviour ◽  
Thermomechanical Properties ◽  
Constitutive Modelling ◽  
High Impact ◽  
The Real ◽  
High Impact Polystyrene ◽  
Different Temperatures ◽  
Thermoforming Process ◽  
Abaqus Software

This paper concerns the experimental and numerical study of the plug-assisted thermoforming process of high impact polystyrene (HIPS). The thermomechanical properties of this polymer were characterized at different temperatures and deformation rates. To study the influence of different parameters in the real conditions of plug-assisted thermoforming process, we carried out “plug-only” tests at different temperatures and plug velocities. To model the deformation behaviour of HIPS, we proposed a thermo-elastic-viscoplastic model, which we have implemented in Abaqus software. A thermo-dependent friction model was also proposed and implemented in Abaqus software. The parameters of the proposed models were identified by the inverse analysis method in the real conditions of plug-assisted thermoforming. The proposed models were validated with “plug-only” tests and plug-assisted thermoforming of yogurt container.

Numerical study of the sheath in magnetized dusty plasma with two-temperature electrons

2014 ◽  
Vol 81 (1) ◽  
Author(s):  
I. Driouch ◽  
H. Chatei ◽  
M. El Bojaddaini
Keyword(s):  
Dusty Plasma ◽  
Numerical Study ◽  
Plasma Sheath ◽  
Hot Electrons ◽  
Dust Grains ◽  
Magnetized Dusty Plasma ◽  
Positive Ions ◽  
Different Temperatures ◽  
Dimensionless Variables ◽  
Two Temperature

Fluid simulations are used to investigate a multi-component magnetized dusty plasma sheath. The model consists of positive ions, dust grains, and two species of electron populations. These electrons are assumed to be a sum of two Maxwellian distributions with two different temperatures (cold and hot). According to multi-fluid equations and some dimensionless variables, the dimensionless equations are obtained and solved numerically. The effect of the presence of the hot electrons in the sheath is examined. A significant change is observed in the quantities characterizing the sheath with respect to one species electrons (cold) assumption.

Presentation of a Numerical 3D Approach to Tackle Thermal Striping in a PWR Nuclear T-Junction

2003 ◽  
Author(s):  
Christophe Pe´niguel ◽  
Marc Sakiz ◽  
Sofiane Benhamadouche ◽  
Jean-Michel Stephan ◽  
Carine Vindeirinho
Keyword(s):  
Numerical Study ◽  
Heat Removal ◽  
Thermal Coupling ◽  
Thermal Fields ◽  
Eddy Simulation ◽  
System A ◽  
Large Eddy ◽  
Piping Systems ◽  
Thermal Striping ◽  
Residual Heat

This paper presents a numerical study to tackle thermal striping phenomena occuring in piping systems. It is here applied to the Residual Heat Removal (RHR) bypass system. A large Eddy Simulation (L.E.S.) approach is used to model the turbulent flow in a T-junction. The thermal coupling between the Finite Volume CFD Code_Saturne and the Finite Element thermal code Syrthes, gives access to the instantaneous field inside the fluid and the solid. By using the instantaneous solid thermal fields, mechanical computations (as presented in (Stephan et al 2002)) are performed to yield the instantaneous mechanical stresses seen by the pipework T-junction and elbow.

Sign in / Sign up

Export Citation Format

Share Document