scholarly journals Design and Analysis of a Valveless Impedance Pump for a Direct Sodium Borohydride–Hydrogen Peroxide Fuel Cell

2020 ◽  
Vol 17 (3) ◽  
Author(s):  
A. S. Yang ◽  
J. W. Tseng ◽  
C. Y. Wen ◽  
H. Zhang
Keyword(s):  
Hydrogen Peroxide ◽  
Stainless Steel ◽  
Fuel Cell ◽  
Sodium Borohydride ◽  
Steel Tube ◽  
Elastic Tube ◽  
Specific Power ◽  
Stainless Steel Tube ◽  
Rubber Tube ◽  
Impedance Pump

Abstract A valveless impedance pump is designed and applied for the first time to supply the liquid fuels for a direct sodium borohydride–hydrogen peroxide fuel cell (DBHPFC). This valveless pump consists of an amber latex rubber tube, which is connected at both ends to rigid stainless-steel tubes of different acoustic impedance, and a simple actuation mechanism with a small direct control (DC) motor and a cam combined. The cam is activated by the motor and periodically compresses the elastic tube at a position asymmetrical from the tube ends. The traveling waves emitted from the compression combine with the reflected waves at the impedance-mismatched rubber tube/stainless-steel tube interfaces. The resulting wave interference creates a pressure gradient and generates a net flow. When connected to a DBHPFC with an active area of 25 cm2, the pump can deliver the fuel at a maximum pumping rate of 30 ml/min, resulting in corresponding DBHPFC maximum power and a current of 13.0 W and 25.5 A, respectively. The specific power, volumetric power density, and back work ratio of the DBHPFC with this pumping method have been proven superior to those of the other pumping configuration with peristaltic pumps. This valveless impedance pump is mechanically simply and less susceptible to corrosion, and it can reduce the volume and weight of fuel cell systems to a measurable extent. The experimental results demonstrate the feasibility of the device for practical DBHPFC applications.

Application of Valve-Less Impedance Pumps to a Direct Sodium Borohydride–Hydrogen Peroxide Fuel Cell

2014 ◽  
Author(s):  
C. Y. Wen ◽  
A. S. Yang ◽  
J. W. Tseng
Keyword(s):  
Hydrogen Peroxide ◽  
Fuel Cell ◽  
Sodium Borohydride ◽  
Elastic Tube ◽  
Specific Power ◽  
Rubber Tube ◽  
Pumping Rate ◽  
Reflected Waves ◽  
Wave Interference ◽  
Peristaltic Pumps

In this study, two novel valve-less impedance pumps are applied, for the first time, in the liquid fuel supply of a Direct Sodium Borohydride–Hydrogen Peroxide Fuel Cell (DBHPFC). This valve-less pump prevents the pump corrosion and serves appropriately to reduce the volume and weight of fuel cell systems. It comprises an amber latex rubber tube, connected at both ends to rigid stainless steel tubes of different acoustic impedance, and a simple actuation mechanism which combines a small DC motor and a cam. The motor activated cam periodically compresses the elastic tube at a position asymmetric from the tube ends. Traveling waves, emitted from the compression, combine with reflected waves at the impedance-mismatched rubber tube/stainless tube interfaces. The resulting wave interference creates a pressure gradient and generates a net flow. A DBHPFC with the active area of 25 cm2 is constructed. It is shown that the maximum pumping rate can achieve 30 ml/min with the DBHPFC connected. The corresponding maximum power and current are 13.0 W and 25.5 A, respectively. Specific power, volumetric power density, and back work ratio of the DBHPFC using this pumping method are shown superior to those of the other pumping configuration with the peristaltic pumps.

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

Production Process and Heat Transfer Performance of 10/316 Clad Tube

2014 ◽  
Vol 1081 ◽  
pp. 270-274
Author(s):  
Zui Xian Yu ◽  
Xue Sheng Wang ◽  
Qin Zhu Chen
Keyword(s):  
Heat Transfer ◽  
Stainless Steel ◽  
Heat Transfer Coefficient ◽  
Carbon Steel ◽  
Transfer Coefficient ◽  
Heat Transfer Performance ◽  
Steel Tube ◽  
Stainless Steel Tube ◽  
Transfer Performance ◽  
Clad Tube

A new preparation technique of carbon steel/stainless steel clad tube was introduced, and the contact surface was well combined. Meanwhile, with the using of tube heat exchanger, the experiment on the heat transfer performance of the clad tube was done. Comparing the 10/316 clad tube and the 316 stainless steel tube, the effects on the heat transfer performance of 316 stainless steel tube attached to carbon steel was evaluated. It is showed that overall heat transfer coefficient of 10/316 clad tubes is higher than that of stainless steel tube. The average heat transfer coefficient of 10/316 clad tubes is about 18.7%~34.4% higher than that of stainless steel tube. Experimental investigation indicates that, by brazing and cold drawing, the 10/316 clad tube was well combined and the thermal conductivity was better than that of stainless steel tube.

Leak tightness of magnetic pulse crimped joints

2012 ◽  
Vol 3 (3) ◽  
pp. 243-250
Author(s):  
A. Loosveld ◽  
W. De Waele ◽  
K. Faes ◽  
O. Zaitov
Keyword(s):  
Stainless Steel ◽  
Steel Tube ◽  
Test Series ◽  
Stainless Steel Tube ◽  
Magnetic Pulse ◽  
Test Procedures ◽  
Burst Test ◽  
Master Thesis ◽  
Leak Tightness ◽  
Sealing Materials

The goal of this master thesis is to realize and investigate leak tightness of joints produced by theelectromagnetic pulse (EMP) crimping process. This way of joining metals has gained more attention lately.With EMP welding, leak tight joints can already be achieved. However, the crimping process has somemajor advantages over EMP welding like the fact that more material combinations are possible and itrequires less energy. To realize the leak tightness, two kinds of sealing materials are used: O-rings andadhesives. The workpieces consist of an aluminium or stainless steel tube which is crimped on a solidaluminium mandrel with circumferential grooves in it. First, some preliminary tests are performed todetermine how much the tubes deform in the grooves. This deformation mainly depends on the appliedcharging voltage and the geometry of the groove. With this information, it is possible to estimate the amountof compression an O-ring would undergo when placed inside this groove. On other workpieces, adhesiveswill be applied. Several test procedures can be conducted on the parts to investigate leak tightness. Theresults of a helium test and a pressure burst test on the first test series conducted at the Walloon researchcentre CEWAC already showed that the use of O-rings can be effective.

Springback law of high-strength 21-6-9 stainless steel tube in numerical control bending under different process parameters

2015 ◽  
Vol 231 (10) ◽  
pp. 1783-1792 ◽  
Author(s):  
Jun Fang ◽  
Shiqiang Lu ◽  
Kelu Wang ◽  
Zhengjun Yao
Keyword(s):  
Stainless Steel ◽  
Friction Coefficient ◽  
Cross Section ◽  
Process Parameters ◽  
High Strength ◽  
Steel Tube ◽  
Numerical Control ◽  
Stainless Steel Tube ◽  
Outer Diameter ◽  
The Cross

In order to achieve the precision bending deformation, the effects of process parameters on springback behaviors should be clarified preliminarily. Taking the 21-6-9 high-strength stainless steel tube of 15.88 mm × 0.84 mm (outer diameter × wall thickness) as the objective, the multi-parameter sensitivity analysis and three-dimensional finite element numerical simulation are conducted to address the effects of process parameters on the springback behaviors in 21-6-9 high-strength stainless steel tube numerical control bending. The results show that (1) springback increases with the increasing of the clearance between tube and mandrel Cm, the friction coefficient between tube and mandrel fm, the friction coefficient between tube and bending die fb, or with the decreasing of the mandrel extension length e, while the springback first increases and then remains unchanged with the increasing of the clearance between tube and bending die Cb. (2) The sensitivity of springback radius to process parameters is larger than that of springback angle. And the sensitivity of springback to process parameters from high to low are e, Cb, Cm, fb and fm. (3) The variation rules of the cross section deformation after springback with different Cm, Cb, fm, fb and e are similar to that before springback. But under same process parameters, the relative difference of the most measurement section is more than 20% and some even more than 70% before and after springback, and a platform deforming characteristics of the cross section deformation is shown after springback.

scholarly journals Acoustic emission characteristics of stress corrosion cracks in a type 304 stainless steel tube

2015 ◽  
Vol 47 (4) ◽  
pp. 454-460 ◽  
Author(s):  
Woonggi Hwang ◽  
Seunggi Bae ◽  
Jaeseong Kim ◽  
Sungsik Kang ◽  
Nogwon Kwag ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Acoustic Emission ◽  
Stress Corrosion ◽  
Steel Tube ◽  
304 Stainless Steel ◽  
Stainless Steel Tube ◽  
Emission Characteristics ◽  
Type 304 ◽  
Type 304 Stainless Steel

Local cholinergic mechanisms mediate nitric oxide-dependent flow-induced vasorelaxation in vitro

1996 ◽  
Vol 270 (2) ◽  
pp. H442-H446 ◽  
Author(s):  
C. M. Martin ◽  
A. Beltran-Del-Rio ◽  
A. Albrecht ◽  
R. R. Lorenz ◽  
M. J. Joyner
Keyword(s):  
Nitric Oxide ◽  
Stainless Steel ◽  
Endothelial Cells ◽  
Steel Tube ◽  
Stainless Steel Tube ◽  
Physiological Salt Solution ◽  
Cholinergic Mechanisms ◽  
Basal Rate ◽  
Prostaglandin F

To determine whether local cholinergic mechanisms evoke nitric oxide (NO)-mediated flow-induced vasorelaxation, canine coronary artery rings without endothelium were suspended beneath an organ chamber that contained a stainless steel tube and a femoral artery segment with endothelium. The rings were superfused at a basal rate of 1 ml/min with physiological salt solution that was bubbled with 95% O2-5% CO2 and maintained at 37 degrees C. They were stretched to optimal length and contracted with prostaglandin F 2 alpha (2 x 10(-6) M). When flow through the stainless steel tube (direct superfusion) was increased from the basal rate of 1 to 4 ml/min, coronary force did not change. Superfusion of the rings (n = 8) with effluent from the femoral segment (endothelial superfusion) at 4 ml/min to study flow-induced vasodilation caused a 67.3 +/- 10.8% relaxation. Treatment of the segment with the NO synthase blocker NG-monomethyl-L-arginine (10(-4) M) eliminated the relaxation seen during endothelial superfusion (P < 0.05 vs. control). Application of atropine (10(-6) M) to additional femoral segments (n = 8) abolished the coronary relaxation observed during endothelial superfusion at 1 ml/ min, and the flow-induced relaxation observed at 4 ml/min was reduced from 64 +/- 8.3 to 27 +/- 5.6% (P < 0.05 vs. control). In studies on additional segments and rings (n = 6), the flow-induced relaxations at 4 ml/min of endothelial superfusion were blunted from 86 +/- 10 to 28 +/- 13% after the segments were treated with acetylcholinesterase (0.00028 U/min for 20 min). These data indicate that basal- and flow-induced release of NO from the vascular endothelium can be mediated by local cholinergic mechanisms. It is possible that flow causes acetylcholine release from certain endothelial cells, which stimulates NO release from these cells or from neighboring endothelial cells.

Nucleate Boiling Heat Transfer of Binary Mixtures at Low to Moderate Heat Fluxes

1999 ◽  
Vol 121 (2) ◽  
pp. 365-375 ◽  
Author(s):  
R. J. Benjamin ◽  
A. R. Balakrishnan
Keyword(s):  
Heat Transfer ◽  
Stainless Steel ◽  
Binary Mixtures ◽  
Boiling Heat Transfer ◽  
Heating Surface ◽  
Nucleate Boiling ◽  
Steel Tube ◽  
Heat Fluxes ◽  
Stainless Steel Tube ◽  
Turbulent Natural Convection

A model for nucleate pool boiling heat transfer of binary mixtures has been proposed based on an additive mechanism. The contributing modes of heat transfer are (i) the heat transferred by microlayer evaporation, (ii) the heat transferred by transient conduction during the reformation of the thermal boundary layer, and (iii) the heat transferred by turbulent natural convection. The model takes into account the microroughness of the heating surface which has been defined quantitatively. The model compares satisfactorily with data obtained in the present study and in the literature. These data were obtained on a variety of heating surfaces such as a vertical platinum wire, a horizontal stainless steel tube and flat horizontal aluminium, and stainless steel surfaces (with various surface finishes) thereby demonstrating the validity of the model.

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