Experimental characterization of meso-scale deformation mechanisms and the RVE size in plastically deformed carbon steel

Meso-scale power systems (10 W to 1000 W) are needed to power untethered mobile robots and assisting devices such as powered exoskeletons. Air-breathing combustion driven actuators, used in a direct acting manner, can be used for such applications and take advantage of the high power density of fluidic actuators and the high energy density of chemical fuels. However, fuel-to-mechanical energy conversion efficiency is critical to make such chemical systems viable over electrical systems. This paper presents the efficiency-based design and experimental characterization of two combustion driven actuators intended to reach high specific power and specific energy. First, efficiency oriented design principles are derived from internal combustion engine theory: (1) an ideal-cycle thermodynamic model of a generic constant volume combustion system suggests that compression ratio and the expansion/compression ratio should both be maximized, and (2) the practical effects of heat, mass and friction losses as well as fuel choice in a small scale combustion chamber context are discussed. Second, two simplified prototypes are built and tested. The first prototype uses a rolling diaphragm seal to limit the effect of mass and friction losses. The second prototype consists of a standard air cylinder that minimizes heat losses by reducing the surface-to-volume ratio of the combustion chamber. Hydrogen is selected as fuel because it allows lean combustion which limits the effect of heat loss with low combustion temperatures. Compression ratio and equivalence ratio are varied experimentally to evaluate their effect on efficiency. Experimental results demonstrate an energy conversion efficiency of 15.3% at a compression ratio of 4.15 and a low equivalence ratio of 0.3. Ragone analysis of relevant meso-scale power systems for mobile robotic suggest that, with proper optimization and system integration, combustion driven power systems can become a viable solution for lightweight and long range meso-scale robotic applications.

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Experimental Characterization of Meso-Scale Processes

From Multiscale Modeling to Meso-Science ◽

10.1007/978-3-642-35189-1_12 ◽

2013 ◽

pp. 431-460

Author(s):

Jinghai Li ◽

Wei Ge ◽

Wei Wang ◽

Ning Yang ◽

Xinhua Liu ◽

...

Keyword(s):

Experimental Characterization ◽

Meso Scale

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Experimental characterization of the solid phase chaotic dynamics in three-phase fluidization

International Journal of Multiphase Flow ◽

10.1016/s0301-9322(97)88294-8 ◽

1996 ◽

Vol 22 ◽

pp. 113

Author(s):

M Cassanello

Keyword(s):

Chaotic Dynamics ◽

Solid Phase ◽

Experimental Characterization ◽

Three Phase

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Experimental characterization of a laminar diffusion flame in micro-gravity

Journal de Chimie Physique ◽

10.1051/jcp:1999190 ◽

1999 ◽

Vol 96 (6) ◽

pp. 1022-1030 ◽

Cited By ~ 3

Author(s):

T. Vietoris ◽

P. Joulain ◽

J. L. Torero

Keyword(s):

Diffusion Flame ◽

Experimental Characterization ◽

Laminar Diffusion Flame ◽

Laminar Diffusion ◽

Micro Gravity

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Experimental Characterization of the Reliability of 3-Terminal Dual-Damascene Copper Interconnect Trees

MRS Proceedings ◽

10.1557/proc-716-b8.13 ◽

2002 ◽

Vol 716 ◽

Cited By ~ 4

Author(s):

C. L. Gan ◽

C. V. Thompson ◽

K. L. Pey ◽

W. K. Choi ◽

F. Wei ◽

...

Keyword(s):

Stress Conditions ◽

Experimental Characterization ◽

Contact Lines ◽

Tree Structures ◽

Similar Test ◽

Dual Damascene ◽

Copper Interconnect ◽

Test Conditions

AbstractElectromigration experiments have been carried out on simple Cu dual-damascene interconnect tree structures consisting of straight via-to-via (or contact-to-contact) lines with an extra via in the middle of the line. As with Al-based interconnects, the reliability of a segment in this tree strongly depends on the stress conditions of the connected segment. Beyond this, there are important differences in the results obtained under similar test conditions for Al-based and Cu-based interconnect trees. These differences are thought to be associated with variations in the architectural schemes of the two metallizations. The absence of a conducting electromigrationresistant overlayer in Cu technology, and the possibility of liner rupture at stressed vias lead to significant differences in tree reliabilities in Cu compared to Al.

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EXPERIMENTAL CHARACTERIZATION OF VVER-440 REACTOR CONTAINMENT TYPE SPRAY NOZZLE

Atomization and Sprays ◽

10.1615/atomizspr.2015011801 ◽

2016 ◽

Vol 26 (3) ◽

pp. 235-255 ◽

Cited By ~ 1

Author(s):

Jeanne Malet ◽

Z. Parduba

Keyword(s):

Spray Nozzle ◽

Experimental Characterization

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Experimental Characterization of Mechanical Behavior of Cord-Rubber Composites

Tire Science and Technology ◽

10.2346/1.2150974 ◽

1982 ◽

Vol 10 (1) ◽

pp. 37-54 ◽

Cited By ~ 11

Author(s):

M. Kumar ◽

C. W. Bert

Keyword(s):

Response Characteristic ◽

Cord Compression ◽

Complete Characterization ◽

Strain Response ◽

Strain Gages ◽

Experimental Characterization ◽

Rubber Composites ◽

Stress Strain ◽

Strain Data

Abstract Unidirectional cord-rubber specimens in the form of tensile coupons and sandwich beams were used. Using specimens with the cords oriented at 0°, 45°, and 90° to the loading direction and appropriate data reduction, we were able to obtain complete characterization for the in-plane stress-strain response of single-ply, unidirectional cord-rubber composites. All strains were measured by means of liquid mercury strain gages, for which the nonlinear strain response characteristic was obtained by calibration. Stress-strain data were obtained for the cases of both cord tension and cord compression. Materials investigated were aramid-rubber, polyester-rubber, and steel-rubber.

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