Internal Low Reynolds-Number Turbulent and Transitional Gas Flow With Heat Transfer

McEligot, Donald M.; Ormand, L. W.; Perkins, H. C.

doi:10.1115/1.3691521

Cited by 51 publications

(34 citation statements)

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“…Figure 4 shows the measured velocity profiles in wall coordinates; here the friction velocity was estimated from the Blasius correlation [Schlichting, 19681. These data show the same behavior as for fully-developed, low-Reynolds-number pipe flow as measured by H. C. Reynolds [1968] and Pate1 and Head[1969] and predicted by McEligot, Ormand and Perkins [1966], H. C. Reynolds [1968] and others. In the turbulent core region velocities are higher than suggested by the so called Universal Velocity Profile and this difference is found to decrease as the Reynolds number increases.…”

Section: Preliminary Checkssupporting

confidence: 68%

Turbulence structure in the viscous layer of strongly heated gas flows

Shehata

McEligot

1995

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For dominant forced convection with significant gas property variation, even in low Mach number flow through a circular tube, apparently the only published profile data available to guide (or test) the development of predictive turbulence models are K. R. Perkins' measurements of mean temperature structure [Perkins, 19751. The work here takes the next step: the frrst mean velocity distributions for this situation are presented.In order to dissect the anatomy of the viscous layer in gaseous, turbulent, tubie flow with strong heating, it has been probed via thermal anemometry coupled with diagnostic application of simple computational thermal fluid dynamics. Experiments for air flowing upward in a vertical circular tube were conducted for heating rates causing significant property variation. An unheated entry of fifty diameters preceeded the heating.Two entry Reynolds numbers of approximately 6000 and 4000 were employed, concentrating on three heating rates, q+ = q"w/Gcp,inTin = 0.0018, 0.00135 and 0.0045, to give conditions considered to be "turbulent," "subturbulent" and "laminarizing," respectively. Exit Reynolds numbers were above 3000 in all cases.Examination emphasizes the wall region which would conventionally be expected to contain the viscous layer, 0 < y+ < -30, if the flow were unheated. In the flow called "turbulent", after being disturbed in the first few diarneters by the heating (and its accompanying variation of viscosity, density and thermal conductivity), profiles representing the turbulence quantities --l/y, E /v, -p UV /'cw and -pc+ 5 /qtvw --appear to recover to approximately selfpreserving conditions. In the other two runs with higher heating rates, the turbulence quantities decrease after the immediate thermal entrance until they are small relative to molecular effects. m DISCLAIMER This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use wouid not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, rnanufacturer, or otherwise does not necessarily constitute or imply its endorsement, m mmendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors ~XPT~SSUI herein do not necessarily state or reflect those of the United States Government or any agency thereof.

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Section: Preliminary Checkssupporting

confidence: 68%

Turbulence structure in the viscous layer of strongly heated gas flows

Shehata

McEligot

1995

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“…Results for the mean velocity are compared in Figure 15 to each other, to other investigators, to a laminar asymptote and to the turbulent "law of the wall." For fully-developed, low-Reynolds-number turbulent flow the levels of the profiles decrease as the Reynolds number is increased until they approach the "law of the wall" or "universal" velocity profile approximately [McEligot, Ormand and Perkins, 1966]. The data for Re = 2510 have the appearance of a Blasius (laminar) boundary layer profile [Schlichting, 1979] when plotted in this form.…”

Section: Turbulence and Velocity Distributions By Laser Doppler Velocmentioning

confidence: 89%

“…Low-Reynolds-number turbulent flow is the term employed to describe the range where the fluid and thermal behavior diverges from high-Reynolds-number asymptotic functions [McEligot, Ormand and Perkins, 1966;Patel and Head, 1969]. In circular tubes the Reynolds number range is approximately from 2500 to 10 4 .…”

Section: Related Workmentioning

confidence: 99%

Measurements of Fundamental Fluid Physics of SNF Storage Canisters

Condie¹,

Creery²,

McEligot³

2001

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SummaryWith the University of Idaho, Ohio State University and Clarksean Associates, this research program has the long-term goal to develop reliable predictive techniques for the energy, mass and momentum transfer plus chemical reactions in drying / passivation (surface oxidation) operations in the transfer and storage of spent nuclear fuel (SNF) from wet to dry storage. Such techniques are needed to assist in design of future transfer and storage systems, prediction of the performance of existing and proposed systems and safety (re)evaluation of systems as necessary at later dates.Many fuel element geometries and configurations are accommodated in the storage of spent nuclear fuel. Consequently, there is no one generic fuel element / assembly, storage basket or canister and, therefore, no single generic fuel storage configuration. One can, however, identify generic flow phenomena or processes which may be present during drying or passivation in SNF canisters. The objective of the INEEL tasks was to obtain fundamental measurements of these flow processes in appropriate parameter ranges.With the University of Idaho, an idealization of a combined drying and passivation approach has been defined in order to investigate the generic flow processes. This simulation includes flow phenomena that occur in canisters for high-enrichment and medium-enrichment fuels, where fuel element spacing in the canister is increased as compared with low enrichment fuel. Canister diameter was taken as 46 cm (18 in.) and a single basket of about 1.3 meters (4 ft.) length was considered. A long central tube ("dip tube") served as the inlet as in one earlier concept for a passivation process; while this concept apparently has not yet been selected for application, it provides an excellent example of the coupled, complex phenomena which may be present in canister flows. Suggested design flow rates for this hypothesized application indicate that the Reynolds number in the inlet tube would be expected to be between 2500 and 5000, i.e., relatively low.The local distributions of convective mass transfer characteristics (drying/passivation) are expected to depend on the freestream turbulence in the flow around stored fuel elements. The magnitudes of this turbulence depend on the turbulence distributions on the upstream side of the perforated basket support plate ("inlet plenum") and, in turn, in the impinging jet and in the inlet tube. This information can assist engineers in understanding variations of surface drying and passivation through an array and approaches to modify designs to counter non-uniformities and to improve iii distribution, as well as providing bases for assessment of computational fluid dynamics codes proposed for the purpose.A water-flow experiment with a 3/4-scale model (relative to the idealized canister) has been used for overall flow visualization and velocity measurements, with and without an array of simulated fuel elements. Observations have been made with perforated plates (representing basket support plates) having...

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“…Three correlations were identified as the most promising candidates for comparison with our data. These include McEligot et al (1966), Petukhov et al (1973), andGnielinski (1976) and will be desribed next.…”

Section: Turbulent Flowmentioning

confidence: 99%

“…In McEligot et al (1966) work, the low Reynolds number gas flow experimental data were used to develop a heat transfer correlation based on the Nusselt number power law or the modified Dittus-Boelter formulation (Eq. 2-3).…”

Section: Mceligot Et Al (1966) Correlationmentioning

confidence: 99%

Investigation of Fundamental Thermal-Hydraulic Phenomena in Advanced Gas-Cooled Reactors

2006

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INL LDRD funded research was conducted at MIT in collaboration with INL personnel to experimentally characterize mixed convection heat transfer in gascooled fast reactor (GFR) core channels. The gas-cooled fast reactor (GFR) for Generation IV has generated considerable interest and is under development in the U.S., France, and Japan. One of the key candidates is a block-core configuration first proposed by MIT, has the potential to operate in Deteriorated Turbulent Heat Transfer (DTHT) regime or in the transition between the DTHT and normal forced or laminar convection regime during post-loss-of-coolant accident (LOCA) conditions. The DTHT regime is defined as a regime where the turbulent heat transfer deteriorates due to either a streamwise flow acceleration effect or a high buoyancy effect. This is contrary to most industrial applications where operation is in a well-defined and well-known turbulent forced convection regime. As a result, important new need emerged to develop heat transfer correlations that make possible rigorous and accurate predictions of Decay Heat Removal (DHR) during post LOCA in these regimes.Extensive literature review on these regimes was performed and a number of the available correlations was collected in: (1) forced laminar, (2) forced turbulent, (3) mixed convection laminar, (4) buoyancy driven DTHT and (5) acceleration driven DTHT regimes. Preliminary analysis on the GFR DHR system was performed and using the literature review results and GFR conditions. It confirmed that the GFR block type core has a potential to operate in the DTHT regime. Further, a newly proposed approach proved that gas, liquid and super critical fluids all behave differently in single channel under DTHT regime conditions, thus making it questionable to extrapolate liquid or supercritical fluid data to gas flow heat transfer.Suggested upgrades for the experimental facility from the 2 nd annual report were successfully installed and the control and data reduction software for facility operation was developed and tested. An extensive development of programming and controlling techniques were introduced for the software development that allowed substantial speed up of data collection and analysis process.Experimental data were collected for three different gases (nitrogen, helium and carbon dioxide) in various heat transfer regimes under a fully developed flow and reasonably uniform wall heat flux conditions. The following ranges of non-dimensional numbers, were covered in the experiment: (1) Reynolds number from 1,800 to 42,700 (2) Jackson' buoyancy parameter up to 5 10 (3) Acceleration parameter up to 6 5 10 and (4) wall to bulk temperature ratio up to 1.88. The data were obtained at various pressures up to 1MPa.Each gas unveiled different physical phenomena. All data basically covered the forced turbulent heat transfer regime, nitrogen data covered the acceleration driven DTHT and buoyancy driven DTHT, helium data covered the mixed convection laminar, acceleration 3 driven DTHT and the laminar to turbu...

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Internal Low Reynolds-Number Turbulent and Transitional Gas Flow With Heat Transfer

Cited by 51 publications

References 0 publications

Turbulence structure in the viscous layer of strongly heated gas flows

Turbulence structure in the viscous layer of strongly heated gas flows

Measurements of Fundamental Fluid Physics of SNF Storage Canisters

Investigation of Fundamental Thermal-Hydraulic Phenomena in Advanced Gas-Cooled Reactors

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