A generalised correlation for the steady state flow in single-phase natural circulation loops



Publisher: Bhabha Atomic Research Centre in Mumbai

Written in English
Published: Pages: 24 Downloads: 297
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Subjects:

  • Fluid dynamics -- Mathematical models.

Edition Notes

Statementby P.K. Vijayan ... [et al.].
SeriesBARC external ;, BARC/2000/E/021
ContributionsVijayan, P. K., Bhabha Atomic Research Centre.
Classifications
LC ClassificationsMicrofiche 2001/60202 (Q)
The Physical Object
FormatMicroform
Pagination24, [12] p.
Number of Pages24
ID Numbers
Open LibraryOL6861007M
LC Control Number00372738

Sieder Tate correlation for laminar flow: Nu = Re/⁄EPr/⁄E H I /⁄E • FLiBe • FLiNaK • KF-ZrF 4 • KCl-MgCl 2 • H 2O (1 atm) Δp = ρ 0 (βΔT)gΔh. 9 Review of Natural/Forced Circulation Loops for MSRs/FHRs Organization NC/FC Experiment Modeling Objective Material Working fluid Max steady-state and transient conditions. A generalized flow correlation for two-phase natural circulation loops MR Gartia, PK Vijayan, DS Pilkhwal Nuclear Engineering and Design (17), , Development of a unified model for the steady-state operation of single-phase natural circulation loops is made by Basu et al.. An unsymmetrical end-notched flexure test is described and its suitability for interfacial fracture toughness testing is evaluated [ 19 ]. Reference: SPE Drift-Flux Parameters for Three-Phase Steady-State Flow in Wellbores; H. Shi, J.A. Holmes, L.R. Diaz, L.J. Durlofsky, K. Aziz The Drift-flux models represent multiphase flow in wellbores or pipes in terms of a number of.

If the mass flow rate is not high enough to circulate the necessary fluid to transport heat from evaporator to condenser, the minipump can be used to promotes natural circulation. For the steady-state condition as is demonstrated in Fig. 21, the mass flux G decreases with increasing heat flux H q for minichannels with minipump (HHCV+P). If used for single-phase flow, these three correlations devolve to the Fanning Gas or Fanning Liquid correlation. When switching from multiphase flow to single-phase flow, the correlation will default to the Fanning. When switching from single-phase flow to multiphase flow, the correlation will default to the Beggs and Brill. The present paper offers an analysis of heat transfer and fluid flow in two phase thermosyphon loop with minichannels. A one-dimensional model of two-phase flow and heat transfer in a closed thermosyphon loop with minichannels was examined. The created general model is based on mass, momentum, and energy balances in the evaporators, rising tube, condensers and the falling tube. A. K. Nayak, M.R. Gartia, and P.K. Vijayan, Thermal-hydraulic Characteristics of a Single-Phase Natural Circulation Loop with Water and Al 2 O 3 Nanofluids, Nuclear Engineering and .

Mathematical modeling and numerical simulation of natural circulation boiling water reactor (NCBWR) are very important in order to study its performance for different designs and various off-design conditions and for design optimization. In the present work, parametric studies of the primary heat transport loop of NCBWR have been performed using lumped parameter models and RELAP5/MOD code. Susyadi and T. Yonomoto, “Analysis on non uniform flow in steam generator during steady state natural circulation cooling,” JAERI-Research , Japan Atomic Energy Research Institute, Ibaraki, Japan, View at: Google Scholar; G. B. Wallis, One-Dimensional Two-Phase Flow, McGraw-Hill Book, New York, NY, USA, P.K. Vijayan,M. R. Gartia, D. S. Pilkhwal, A. K. Nayak and D. Saha, Steady State Flow In Single-Phase And Two-Phase Natural Circulation Loops, Special session on ‘Single and two-phase natural circulation loops, 3rd IASME / WSEAS International Conference on Heat transfer, Thermal engineering and Environment, August , Corfu Island, Greece. theoretical and experimental studies concerned with natural circulation loops, and modelling methods describing steady state flows, transient and stability characteristics. Ramos (Ramos et al., ) performed the theoreti cal study of the steady state flow in the.

A generalised correlation for the steady state flow in single-phase natural circulation loops Download PDF EPUB FB2

A generalized equation for the steady state flow in single-phase natural circulation loops was derived based on 1-D theory by assuming the loop to be partly in laminar and partly in transition or turbulent flow.

The derived dimensionless flow equation is applicable for any loop obeying multiple friction by: STEADY STATE FLOW IN SINGLE-PHASE AND TWO-PHASE NATURAL CIRCULATION LOOPS P.K. Vijayan, M.R. Gartia, al A.K. Nayak and D. Saha Reactor Engineering Division, Bhabha Atomic Research Centre, Trombay, MumbaiE-mail: [email protected] Abstract Derivation of a steady state flow correlation valid for both single- and two.

The steady-state natural circulation flow solution obtained was shown to be a function of a dimensionless group PY or (NuGr/Pr) Y and agrees very well. A generalised correlation for the steady state flow in single-phase natural circulation loop, Report BARC/ /E/, Bhabha Atomic Research Centre, Mumbai, India,   Effect of the heater and cooler orientations on the single-phase natural circulation was studied in a rectangular loop.

From steady state considerations, the maximum flow for a specified operating condition is achievable for the orientation with both the heater and the cooler by:   Also plotted in the figure arc Natural drculallon dala oForced flow data Equatio n (9) FIG.

The effective hydraulic loss coefficient for forced and natural circulation flow On the steady-state performance of natural circulation loops NATURAL CIRCULATION DATA FORCED FLOW CORRELATIONS ^-EQUATION (10) FIG. A generalized correlation has been proposed to estimate the steady-state flow in two-phase natural circulation loops.

The steady-state governing equations for homogeneous equilibrium model, viz. continuity, momentum and energy equations have been solved to obtain the dimensionless flow rate as a function of a modified Grashof number and a geometric by:   While using the subcritical natural circulation flow correlation for supercritical data, it was not able to predict the steady state flow accurately near supercritical pressure condition.

A generalized correlation has been proposed to estimate the steady state flow in supercritical natural circulation loops based on a relationship between. An experiment to investigate the natural circulation of cryogenic liquid has been performed. The study is motivated mainly by our recent development of cryogenic cooling system for prototype superconducting cyclotron without any circulating pump.

In the natural circulation loop system, a cooling channel is attached on the outer surface of the aluminum block and the liquid nitrogen passes. To establish the heat transport capability of natural circulation loops, it is essential to know the flow rate.

In this paper, the following generalized correlation for steady state flow valid for. The steady state data from the five different two-phase natural circulation loops are compared with the theoretical correlation for turbulent flow in Fig.

9 as all the data fall in this regime. The. A Generalized Flow Equation for Single-Phase Natural Circulation Loops Obeying Multiple Friction Laws,” Steady-State and Stability Characteristics of a Single-Phase Natural Circulation in a Rectangular Loop With Different Heater and Cooler Orientations,” A Generalized Flow Correlation for Single-Phase Natural Circulation Loops,”.

Vijayan PK, Bade MH, Saha D, Sinha RK, Venkat RV () A generalized flow correlation for single-phase natural circulation loops. In: Proceedings of the 17th National and 6th ISHMT/ASME heat and mass transfer conference, Kalpakkam, India.

Heat and Mass Transfer, and Properties of Working Fluids and Materials; Published: 11 October The generalized correlation for the evaluation of the influence of the Stefan flow on the heat transfer coefficient.

A generalized correlation has been proposed to estimate the steady-state flow in two-phase natural circulation loops. The steady-state governing equations for homogeneous equilibrium model, viz. Effect of Geometric Parameters on Steady-State Performance of Single-Phase Natural Circulation Loop With Heat Loss to Ambient Experimental Observations on the General Trends of the Steady State and Stability Behaviour of Single-Phase Natural Circulation Loops,” A Generalized Flow Correlation For Single-Phase Natural Circulation Loops.

Development of generalised correlation for steady state behaviour of singlephase natural circulation loops and investigations on the suppression of instability using helical B Mukund Haribhau M.E.

Thesis, Walchand College of Engineering, Sangli, Shivaji University 3. Two-Phase Natural Circulation. Two-phase natural circulation experiments were conducted in four uniform diameter loops of inside diameter 7, and mm with the length scales as shown in Figure 6(a).The steam separator, the condenser, and the associated piping (the portion inside the rectangular box in Figure 6(a)) were the same for all the loops.

devoted to transient and steady state behavior, as well as to stability analysis of the system under various heating and cooling conditions.

Vijayan et al.3 studied effect of the heater and cooler orientations on the single-phase natural circulation in a rectangular loop.

From steady state considerations, the maximum flow for a specified. A generalized correlation has been proposed to estimate the steady-state flow in two-phase natural circulation loops. The steady-state governing equations for homogeneous equilibrium model, viz.

continuity, momentum and energy equations have been solved to obtain the dimensionless flow. Natural circulation loop (NCL) serves as a passive cooling system in many applications such as in nuclear power plants, solar water heaters, transformers, geothermal power extraction etc.

Steady st. performed at steady state inlet temperature of 35℃. Fig. equation for single phase natural circulation loops obeying multiple friction laws, International Journal of Heat and Mass D.S. Pilkhwal, A generalized flow correlation for two-phase natural circulation loops, Nuclear Engineering and Design, Vol, p, [3] R.

In the present investigation, the steady state performance of a rectangular single phase natural circulation loop (NCL) with end heat exchangers is studied. One-dimensional governing equations are considered in developing the mathematical model. Analytical expressions are derived for the circulation rate and temperature profile.

Steady state performance of single-phase loops The Generalized flow correlations were found useful to compare the performance of various loops Uniform diameter loops (UDLs) Nonuniform diameter loops (NDLs) Database for UDLs Total Number of loops: 14 Loop diameter: 6 to 40 mm Loop height: to m Total circulation length: to m L t.

single-phase natural circulation loop Vienna, Austria, September24 BARC. Two Phase Natural Circulation. A generalized flow correlation of the same form as that of single-phase has been developed (Gartia et al.

()) to estimate the steady state flow rate in two-phase natural circulation loops which is given by, Re ss C Grm N G.

Steady State Flow and Static Instability of Supercritical Natural Circulation Loops,” A Generalized Flow Equation for Single Phase Natural Circulation Loops Obeying Multiple Friction Laws,” Thermal Sciences/Engineering Data Book, Allied Publishers, New Delhi, India. Petukhov, B. A model to predict the steady-state behavior of a rectangular two-phase natural circulation loop has been proposed.

The analysis employs a one-dimensional two-fluid model to identify various system parameters, with particular emphasis on the subcooled boiling region. The relationships for the calculation of the coefficients taking into account an increase in the mass output and an increase or a decrease in the heat emission (depending on the directions of the heat-and-mass flows) as a result of the influence of the Stefan flow are presented.

Vijayan, P. Experimental observations on the general trends of the steady state and stability behaviour of single-phase natural circulation loops. Nucl. Eng. Des., – [Google Scholar] Turgut, A.; Doganay, S. Thermal performance of a single phase natural circulation mini loop working with nanofluid.

High Temp. can be expressed by a generalized correlation in terms of a single dimensionless parameter. The experimental data from both single-phase and two-phase loops are found to be in reasonable agreement with this correlation. The generalized steady flow correlation has also been compared with code predictions.

Introduction Natural circulation. circulation loops, explicit correlations for steady state flow are not available. This makes it difficult to compare the performance of different two-phase natural circulation loops. Therefore, we present an analytical correlation for steady state flow, which is then non-dimensionalized to obtain a generalized correlation.

This generalized.STNI Science and Technology of Nuclear Installations Hindawi Publishing Corporation // Research Article Effect of Loop Diameter on the Steady State and Stability Behaviour of Single-Phase and Two-Phase Natural Circulation Loops Vijayan P.

K. 1 Nayak A. K. 1 Saha D. 1 Gartia M. R. 1 Cleveland.A generalized flow equation for single phase natural circulation loops obeying multiple friction laws. Int. J. Heat Mass Transf.54, – [Google Scholar] Thomas, S.; Sobhan, C.B. Stability and transient performance of vertical heater vertical cooler natural circulation loops with metal oxide nanoparticle suspensions.

J.