Fin configurations to reduce lauric acid melting time in a rectangular thermal reservoir

Lauric Acid-Induced Thrombocytopenia and Thrombosis in Rabbits

Thrombosis and Haemostasis ◽

10.1055/s-0038-1655016 ◽

1967 ◽

Vol 18 (01/02) ◽

pp. 057-065 ◽

Cited By ~ 3

Author(s):

G Zbinden

Keyword(s):

Acid Solution ◽

Intravenous Injection ◽

Lauric Acid ◽

Repeated Administration ◽

Intravenous Dose ◽

Acid Injection ◽

Small Doses ◽

High Doses

SummaryIntravenous injection of 0.5% lauric acid solution into rabbits caused moderate to marked thrombocytopenia. With small doses (2.5 mg/kg) this thrombocyte decrease was reversible and microscopically demonstrable thrombosis in the lungs was only seen or suspected in a small number of rabbits 10 to 30 min after lauric acid injection. High doses were followed by partly reversible thrombocytopenia and by moderate to marked, sometimes lethal, thrombosis in the lungs still demonstrable 24 hrs after injection. Repeated administration of small doses of lauric acid did not lead to a depletion of the circulating thrombocytes. Thrombocytopenic response, however, appeared to be less pronounced after the second and subsequent injections. Studies with Cr51-labeled platelets indicate that during the reversible thrombocytopenia following a small intravenous dose of lauric acid platelets are retained in various organs, particularly the lungs.

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The chemical composition and estimated minimum thermal reservoir temperatures of selected hot springs in Oregon

Open-File Report ◽

10.3133/ofr741067 ◽

1974 ◽

Cited By ~ 7

Author(s):

R.H. Mariner ◽

J.B. Rapp ◽

L.M. Willey ◽

T. S. Presser

Keyword(s):

Chemical Composition ◽

Hot Springs ◽

Thermal Reservoir

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Thermal Energy Storage Through Melting of a Commercial Phase Change Material in an Annulus with Radially Divergent Longitudinal Fins

International Journal of Thermofluid Science and Technology ◽

10.36963/ijtst.20070102 ◽

2020 ◽

Vol 7 (1) ◽

Author(s):

Tonny Tabassum Mainul Hasan ◽

Latifa Begum

Keyword(s):

Energy Storage ◽

Phase Change ◽

Phase Change Material ◽

Thermal Energy ◽

Thermal Energy Storage ◽

Storage System ◽

Operating Conditions ◽

Melting Time ◽

Bottom Part ◽

Change Material

This study reports on the unsteady two-dimensional numerical investigations of melting of a paraffin wax (phase change material, PCM) which melts over a temperature range of 8.7oC. The PCM is placed inside a circular concentric horizontal-finned annulus for the storage of thermal energy. The inner tube is fitted with three radially diverging longitudinal fins strategically placed near the bottom part of the annulus to accelerate the melting process there. The developed CFD code used in Tabassum et al., 2018 is extended to incorporate the presence of fins. The numerical results show that the average Nusselt number over the inner tube surface, the total melt fraction, the total stored energy all increased at every time instant in the finned annulus compared to the annulus without fins. This is due to the fact that in the finned annulus, the fins at the lower part of the annulus promotes buoyancy-driven convection as opposed to the slow conduction melting that prevails at the bottom part of the plain annulus. Fins with two different heights have been considered. It is found that by extending the height of the fin to 50% of the annular gap about 33.05% more energy could be stored compared to the bare annulus at the melting time of 82.37 min for the identical operating conditions. The effects of fins with different heights on the temperature and streamfunction distributions are found to be different. The present study can provide some useful guidelines for achieving a better thermal energy storage system.

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Design and Construction of a Laboratory-Scale Direct-Current Electric Arc Furnace for Metallurgical and High-Titanium Slag Smelting Studies

Metals ◽

10.3390/met11050732 ◽

2021 ◽

Vol 11 (5) ◽

pp. 732

Author(s):

Botao Xue ◽

Lingzhi Yang ◽

Yufeng Guo ◽

Feng Chen ◽

Shuai Wang ◽

...

Keyword(s):

Direct Current ◽

Electric Arc Furnace ◽

Electric Arc ◽

Melting Time ◽

Furnace Lining ◽

Arc Furnace ◽

Titanium Slag ◽

Design Requirements ◽

Metallized Pellets ◽

The Heat Balance

A novel direct-current electric arc furnace (DC-EAF) was designed and constructed in this study for experimentally investigating high-titanium slag smelting, with an emphasis on addressing the issues of incomplete separation of metal and slag as well as poor insulation effects. The mechanical components (crucible, electrode, furnace lining, etc.) were designed and developed, and an embedded crucible design was adopted to promote metal-slag separation. The lining and bottom thicknesses of the furnace were determined via calculation using the heat balance equations, which improved the thermal insulation. To monitor the DC-EAF electrical parameters, suitable software was developed. For evaluating the performance of the furnace, a series of tests were run to determine the optimal coke addition under the conditions of constant temperature (1607 °C) and melting time (90 min). The results demonstrated that for 12 kg of titanium-containing metallized pellets, 4% coke was the most effective for enrichment of TiO2 in the high-titanium slag, with the TiO2 content reaching 93.34%. Moreover, the DC-EAF met the design requirements pertaining to lining thickness and facilitated metal-slag separation, showing satisfactory performance during experiments.

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Effect of Twisted Fin Array in a Triple-Tube Latent Heat Storage System during the Charging Mode

Sustainability ◽

10.3390/su13052685 ◽

2021 ◽

Vol 13 (5) ◽

pp. 2685

Author(s):

Mohammad Ghalambaz ◽

Jasim M. Mahdi ◽

Amirhossein Shafaghat ◽

Amir Hossein Eisapour ◽

Obai Younis ◽

...

Keyword(s):

Energy Storage ◽

Heat Exchanger ◽

Latent Heat ◽

Thermal Energy ◽

Heat Storage ◽

Hot Water ◽

Melting Time ◽

Latent Heat Storage ◽

Tube Heat Exchanger ◽

Storage Rate

This study aims to assess the effect of adding twisted fins in a triple-tube heat exchanger used for latent heat storage compared with using straight fins and no fins. In the proposed heat exchanger, phase change material (PCM) is placed between the middle annulus while hot water is passed in the inner tube and outer annulus in a counter-current direction, as a superior method to melt the PCM and store the thermal energy. The behavior of the system was assessed regarding the liquid fraction and temperature distributions as well as charging time and energy storage rate. The results indicate the advantages of adding twisted fins compared with those of using straight fins. The effect of several twisted fins was also studied to discover its effectiveness on the melting rate. The results demonstrate that deployment of four twisted fins reduced the melting time by 18% compared with using the same number of straight fins, and 25% compared with the no-fins case considering a similar PCM mass. Moreover, the melting time for the case of using four straight fins was 8.3% lower than that compared with the no-fins case. By raising the fins’ number from two to four and six, the heat storage rate rose 14.2% and 25.4%, respectively. This study presents the effects of novel configurations of fins in PCM-based thermal energy storage to deliver innovative products toward commercialization, which can be manufactured with additive manufacturing.

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A Kinetic Model for the Modification of Al2O3 Inclusions during Calcium Treatment in High-Carbon Hard Wire Steel

Materials ◽

10.3390/ma14051305 ◽

2021 ◽

Vol 14 (5) ◽

pp. 1305

Author(s):

Zuobing Xi ◽

Changrong Li ◽

Linzhu Wang

Keyword(s):

Kinetic Model ◽

Early Stage ◽

Morphological Evolution ◽

Product Layer ◽

Melting Time ◽

Calcium Treatment ◽

High Carbon ◽

Inclusion Modification ◽

Shrinking Core ◽

Wire Steel

Laboratory-scale experiments for the modification of Al2O3 inclusions by calcium treatment in high-carbon hard wire steel were performed and the compositions and morphological evolution of inclusions were studied. The kinetics of the modification of Al2O3 inclusions by calcium treatment were studied in high-carbon hard wire steel based on the unreacted shrinking core model, considering the transfer of Ca and Al through the boundary layer and within the product layer, coupled with thermodynamic equilibrium at the interfaces. The diffusion of Al in the inclusion layer was the limiting link in the inclusion modification process. The Ca concentration in molten steel had the greatest influence on the inclusion modification time. The modification time for inclusions tended to be longer in the transformation of higher CaO-containing calcium aluminate. The modification of Al2O3 into CA6 was fastest, while the most time was needed to modify CA into C12A7. It took about six times time longer at the later stage of inclusion modification than at the early stage. The complete modification time for inclusions increased with the square of their radii. The changes of CaO contents with melting time were estimated based on a kinetic model and was consistent with experimental results.

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