scholarly journals Estimations on Properties of Redox Reactions to Electrical Energy and Storage Device of Thermoelectric Pipe (TEP) Using Polymeric Nanofluids

Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1812
Author(s):  
Qin Gang ◽  
Rong-Tsu Wang ◽  
Jung-Chang Wang
Keyword(s):  
Thermal Conductivity ◽  
Power Density ◽  
Heat Dissipation ◽  
Electrical Energy ◽  
Steel Tube ◽  
Storage Device ◽  
Stainless Steel Tube ◽  
The Novel ◽  
Empirical Formulas ◽  
Dissipative Heat

A thermoelectric pipe (TEP) is constructed by tubular graphite electrodes, Teflon material, and stainless-steel tube containing polymeric nanofluids as electrolytes in this study. Heat dissipation and power generation (generating capacity) are both fulfilled with temperature difference via the thermal-electrochemistry and redox reaction effects of polymeric nanofluids. The notion of TEP is to recover the dissipative heat from the heat capacity generated by the relevant machine systems. The thermal conductivity and power density empirical formulas of the novel TEP were derived through the intelligent dimensional analysis with thermoelectric experiments and evaluated at temperatures between 25 and 100 °C and vacuum pressures between 400 and 760 torr. The results revealed that the polymeric nanofluids composed of titanium dioxide (TiO2) nanoparticles with 0.2 wt.% sodium hydroxide (NaOH) of the novel TEP have the best thermoelectric performance among these electrolytes, including TiO2 nanofluid, TiO2 nanofluid with 0.2 wt.% NaOH, deionized water, and seawater. Furthermore, the thermal conductivity and power density of the novel TEP are 203.1 W/(m·K) and 21.16 W/m3, respectively.

The Thermal Properties of Human Blood during the Freezing Process

1973 ◽  
Vol 95 (2) ◽  
pp. 246-249 ◽  
Author(s):  
F. C. Wessling ◽  
P. L. Blackshear
Keyword(s):  
Thermal Conductivity ◽  
Thermal Properties ◽  
Water Solution ◽  
Time History ◽  
Steel Tube ◽  
Ice Crystals ◽  
Freezing Process ◽  
Stainless Steel Tube ◽  
History Of ◽  
Temperature Time

This paper presents calculations of the density, thermal conductivity, and enthalpy of blood during the freezing process. The calculations are based upon the premise that blood freezes similarly to a mixture of fats, proteins, and sodium chloride in a water solution and freezes so that ice crystals align themselves with the direction of heat flow. The properties were checked by calculating the theoretical temperature–time history of blood freezing in a Teflon-coated stainless-steel tube and comparing the results with experiments. The agreement was within 10 percent over the entire ranges of temperature and time. Hence the derived thermal properties are concluded to be good approximations to the real properties.

Convective Heat Transfer of Nanofluids (DI Water-Al2O3) in Micro-Channels

2007 ◽  
Author(s):  
Joohyun Lee ◽  
Roger D. Flynn ◽  
Kenneth E. Goodson ◽  
John K. Eaton
Keyword(s):  
Heat Transfer ◽  
Thermal Conductivity ◽  
Stainless Steel ◽  
Convective Heat Transfer ◽  
Convective Heat ◽  
Volume Concentration ◽  
Tube Wall ◽  
Steel Tube ◽  
Stainless Steel Tube ◽  
Micro Channels

The convection performance of nanofluids in microchannels has received relatively little attention. This work reports convective heat transfer experiments of deionized water/Al2O3 nanofluids using 200μm hydraulic diameter MEMs fabricated microchannel structures and a stainless steel tube with 250μm inside diameter. The tube wall is heated electrically producing a constant heat flux boundary condition and an infrared camera is used to measure the outside tube wall temperature. A full numerical conjugate analysis of the apparatus is used to infer the fluid thermal conductivity from the temperature measurements. The effective thermal conductivity of nanofluids increased only by 4% for 4% volume concentration nanofluids in the MEMs fabricated microchannel and 5% for 3% volume concentration in the stainless steel tube under laminar flow conditions. The effective viscosity of the nanofluids increased 12% for 2% volume concentration. A dynamic light scattering system was used to measure the effective particle diameter and particle size distributions of nanoparticles with various pH values and surfactants. The measured mean diameter of Al2O3 nanoparticle is 170 nm, which is larger than the 40–50 nm nominal size.

Convective Heat Transfer With Nanofluids in a Single 1.02-mm Tube

2006 ◽  
Author(s):  
W. Y. Lai ◽  
B. Duculescu ◽  
P. E. Phelan ◽  
R. S. Prasher
Keyword(s):  
Heat Transfer ◽  
Thermal Conductivity ◽  
Convective Heat Transfer ◽  
Convective Heat ◽  
Steel Tube ◽  
Deionized Water ◽  
Stainless Steel Tube ◽  
Al2o3 Nanoparticles ◽  
Fluid Temperature ◽  
Colloidal Solutions

Nanofluids are heat transfer liquids which contain small volume fractions of suspended nanoparticles, with sizes smaller than 100 nm, in colloidal solutions. Numerous experiments on the static thermal conductivity of these fluids have revealed a greater-than-expected effective thermal conductivity, and thus there is interest in utilizing nanofluids for heat transfer applications. The nanofluid thermal performance under convective heat transfer conditions is of even greater interest. Therefore, we report here our initial convection experiments with nanofluids. Our experimental test section consists of a single millimeter-size, stainless steel tube subjected to constant wall heat flux. The cooling nanofluids, flowed through the test tube, consist of Al2O3 nanoparticles and deionized water. Both wall temperature and fluid temperature are measured. Compared with base fluid, the Nu of 20-nm Al2O3-deionized water nanofluids had 8% enhancement for φ = 1 vol% but only 3% for φ = 0.5 vol% at Re = 270. Based on the results, the utility of convective heat sinks containing nanofluids are evaluated for contemporary uses.

MeV Ion-Beam Bombardment Effects on The Thermoelectric Figures of Merit of Zn4Sb3 and ZrNiSn-Based half-heusler compounds

2007 ◽  
Vol 1020 ◽  
Author(s):  
S. Budak ◽  
S. Guner ◽  
C. Muntele ◽  
C. C. Smith ◽  
B. Zheng ◽  
...  
Keyword(s):  
Thin Films ◽  
Thermal Conductivity ◽  
Seebeck Coefficient ◽  
Measurement System ◽  
Ion Beam ◽  
Electrical Energy ◽  
Figures Of Merit ◽  
Material Systems ◽  
The Cross ◽  
Conductivity Of Thin Films

AbstractSemiconducting â-Zn4Sb3and ZrNiSn-based half-heusler compound thin films were prepared by co-evaporation for the application of thermoelectric (TE) materials. High-purity solid zinc and antimony were evaporated by electron beam to grow the â-Zn4Sb3thin film while high-purity zirconium powder and nickel tin powders were evaporated by electron beam to grow the ZrNiSn-based half-heusler compound thin film. Rutherford backscattering spectrometry (RBS) was used to analyze the composition of the thin films. The grown thin films were subjected to 5 MeV Si ions bombardments for generation of nanostructures in the films. We measured the thermal conductivity, Seebeck coefficient, and electrical conductivity of these two systems before and after 5 MeV Si ions beam bombardments. The two material systems have been identified as promising TE materials for the application of thermal-to-electrical energy conversion, but the efficiency still limits their applications. The electronic energy deposited due to ionization in the track of MeV ion beam can cause localized crystallization. The nanostructures produced by MeV ion beam can cause significant change in both the electrical and the thermal conductivity of thin films, thereby improving the efficiency. We used the 3ù-method measurement system to measure the cross-plane thermal conductivity ,the Van der Pauw measurement system to measure the cross-plane electrical conductivity, and the Seebeck-coefficient measurement system to measure the cross-plane Seebeck coefficient. The thermoelectric figures of merit of the two material systems were then derived by calculations using the measurement results. The MeV ion-beam bombardment was found to decrease the thermal conductivity of thin films and increase the efficiency of thermal-to-electrical energy conversion.

Transformations of hydrocarbon radicals moving along a stainless steel tube

2010 ◽  
Vol 4 (6) ◽  
pp. 928-934
Author(s):  
A. E. Gorodetskii ◽  
V. L. Bukhovets ◽  
R. Kh. Zalavutdinov ◽  
A. P. Zakharov
Keyword(s):  
Stainless Steel ◽  
Steel Tube ◽  
Stainless Steel Tube ◽  
Hydrocarbon Radicals

The Effects of Nucleate Boiling Versus Film Boiling on Heat Transfer in Power Boiler Tubes

1962 ◽  
Vol 84 (4) ◽  
pp. 365-371 ◽  
Author(s):  
H. S. Swenson ◽  
J. R. Carver ◽  
G. Szoeke
Keyword(s):  
Heat Transfer ◽  
Nucleate Boiling ◽  
Steel Tube ◽  
Heat Fluxes ◽  
Inside Surface ◽  
Film Boiling ◽  
Stainless Steel Tube ◽  
Transfer Coefficients ◽  
Steam Quality ◽  
Heat Transfer Coefficients

In large, subcritical pressure, once-through power boilers heat is transferred to steam and water mixtures ranging in steam quality from zero per cent at the bottom of the furnace to 100 per cent at the top. In order to provide design information for this type of boiler, heat-transfer coefficients for forced convection film boiling were determined for water at 3000 psia flowing upward in a vertical stainless-steel tube, AISI Type 304, having an inside diameter of 0.408 inches and a heated length of 6 feet. Heat fluxes ranged between 90,000 and 180,000 Btu/hr-sq ft and were obtained by electrical resistance heating of the tube. The operation of the experimental equipment was controlled so that nucleate boiling, transition boiling, and stable film boiling occurred simultaneously in different zones of the tube. The film boiling data were correlated with a modified form of the equation Nu = a a(Re)m(Pr)n using steam properties evaluated at inside surface temperature. Results of a second series of heat-transfer tests with tubes having a helical rib on the inside surface showed that nucleate boiling could be maintained to much higher steam qualities with that type of tube than with a smooth-bore tube.

Thermal Conductivity Performance Modeling and Characterization of a Novel Anisotropic Conductive Adhesive Used in Lead-Free Electronics Packaging

2012 ◽  
Author(s):  
Matthew J. Combs ◽  
S. Manian Ramkumar ◽  
Satish Kandlikar
Keyword(s):  
Thermal Conductivity ◽  
Base Material ◽  
Bond Line ◽  
Thermal Interface Material ◽  
The Novel ◽  
Conductive Adhesives ◽  
Curing Conditions ◽  
Bond Line Thickness ◽  
Significant Research ◽  
American Society

The continued desire to utilize an alternative to lead-based solder materials for electrical interconnections has led to significant research interest in Anisotropic Conductive Adhesives (ACAs). The use of ACAs in electrical connections creates bonds using a combination of metal particles and epoxies to replace solder. The novel ACA discussed in this paper allows for bonds to be created through aligning columns of conductive particles along the Z-axis. These columns are formed by the application of a magnetic field, during the curing process. The benefit of this novel ACA is that it does not require precise printing of the adhesive on pads and also enables the mass curing without creating shorts in the circuitry. This paper will present the findings of the thermal conductivity performance tests using the novel ACA and its applicability as a thermal interface material and for assembling bottom termination components, power devices, etc. The columns that act as electrical conduction paths also contribute towards the thermal conductivity. The thermal conductivity of the novel ACA was measured utilizing a system that is similar to that in ASTM (American Society of Testing Materials) D5470 standard. The goal was to examine the influence of Bond Line Thickness (BLT), particle loading densities, particle diameters and adhesive matrix curing conditions on the electrical and thermal performance of the novel ACA. This paper will also present a numerical model to describe the thermal behavior of the novel ACA. The novel ACA’s applicability for PCB-level assembly has also been successfully demonstrated by RIT, including base material characterization, effect of process parameters, failures, and long-term reliability. Reliability testing included the investigation of the assembly performance in temperature and humidity aging, thermal aging, air-to-air thermal cycling, and drop testing.

Sign in / Sign up

Export Citation Format

Share Document