A study on the effect of double-tip inclined angle on micro-scratching process using smooth particle hydrodynamic method

Biomaterial direct-write technologies have been receiving more and more attention as rapid prototyping innovations in the area of tissue engineering, regenerative medicine, and biosensor∕actuator fabrication based on computer-aided designs. However, cell damage due to the mechanical impact during cell direct writing has been observed and is a possible hurdle for broad applications of fragile cell direct writing. The objective of this study is to investigate the impact-induced cell mechanical loading profile in cell landing in terms of stress, acceleration, and maximum shear strain component during cell direct writing using a mesh-free smooth particle hydrodynamic method. Such cell mechanical loading profile information can be used to understand and predict possible impact-induced cell damage. It is found that the cell membrane usually undergoes a relatively severe deformation and the cell mechanical loading profile is dependent on the cell droplet initial velocity and the substrate coating thickness. Two important impact processes may occur during cell direct writing: the first impact between the cell droplet and the substrate coating and the second impact between the cell and the substrate. It is concluded that the impact-induced cell damage depends not only on the magnitudes of stress, acceleration, and∕or shear strain but also the loading history that a cell experiences.

Download Full-text

Pitching Angle on Space Capsule Water Landing Using Smooth Particle Hydrodynamic Method

Journal of Spacecraft and Rockets ◽

10.2514/1.a33760 ◽

2017 ◽

Vol 54 (3) ◽

pp. 743-754 ◽

Cited By ~ 1

Author(s):

Zhaoyan Lu ◽

Tianhang Xiao ◽

Zhengzhou Li ◽

Zhenming Zhang ◽

Sha Du ◽

...

Keyword(s):

Smooth Particle Hydrodynamic ◽

Smooth Particle Hydrodynamic Method ◽

Hydrodynamic Method ◽

Space Capsule

Download Full-text

Modeling and Analysis of the Droplet Landing Process in Cell Direct-Writing

International Journal of Automation Technology ◽

10.20965/ijat.2013.p0353 ◽

2013 ◽

Vol 7 (3) ◽

pp. 353-358 ◽

Cited By ~ 1

Author(s):

Cai Renye ◽

◽

Huang Jin ◽

Keyword(s):

Large Scale ◽

Cell Damage ◽

Three Dimensional ◽

Smooth Particle Hydrodynamic ◽

Direct Write ◽

Direct Writing ◽

Modeling And Analysis ◽

Mesh Free ◽

Hydrodynamic Method ◽

The Impact

Cell direct-write, a promising technology for the creation of complex, three-dimensional tissue constructs, has great potential in tissue engineering, biological cytology, high-throughput drug screening and cell sensors. However, it has been found that cell damage due to the mechanical impact during cell direct-write is a possible hurdle for broad applications of fragile cell direct writing. The objective of this paper is to analyze the impact of the continuously jetted cell droplets on the hydro-gel coating substrate. In order to avoid the element distortion due to large-scale deformation, a mesh-free Smooth Particle Hydrodynamic method (SPH), is introduced to study the impact-induced cell mechanical loading profile during cell landing, including effective stress, plastic strain, velocity and acceleration, for better understanding and prediction of possible impact-induced cell damage. It is found that three important impact processes, cell-hydrogel, cellcell and cell-substrate impact, may occur during cell landing. It is concluded to decrease impact-induced cell damage, there are an appropriate firing period and jetting velocity.

Download Full-text

EFFECT OF INCLINED ANGLE OF PIN ARRAYS ON FLOW AND HEAT TRANSFER CHARACTERISTICS IN FLOW CHANNEL

10.1615/ihtc16.hte.023884 ◽

2018 ◽

Author(s):

P. Narato ◽

Makatar Wae-hayee ◽

Mohd Zulkifly Abdullah ◽

Chayut Nuntadusit

Keyword(s):

Heat Transfer ◽

Flow Channel ◽

Heat Transfer Characteristics ◽

Transfer Characteristics ◽

Flow And Heat Transfer ◽

Inclined Angle

Download Full-text

The Effect of Void Arrangement on the Pattern Transformation of Porous Soft Solids under Biaxial Loading

Materials ◽

10.3390/ma14051205 ◽

2021 ◽

Vol 14 (5) ◽

pp. 1205

Author(s):

Hai Qiu ◽

Ying Li ◽

Tianfu Guo ◽

Shan Tang ◽

Zhaoqian Xie ◽

...

Keyword(s):

Biaxial Loading ◽

Tensile Deformation ◽

Biaxial Stress ◽

Porous Solids ◽

Biaxial Compression ◽

Structural Topology ◽

Soft Solids ◽

Tension And Compression ◽

Inclined Angle ◽

Pattern Transformation

Structural topology and loading condition have important influences on the mechanical behaviors of porous soft solids. The porous solids are usually set to be under uniaxial tension or compression. Only a few studies have considered the biaxial loads, especially the combined loads of tension and compression. In this study, porous soft solids with oblique and square lattices of circular voids under biaxial loadings were studied through integrated experiments and numerical simulations. For the soft solids with oblique lattices of circular voids, we found a new pattern transformation under biaxial compression, which has alternating elliptic voids with an inclined angle. This kind of pattern transformation is rarely reported under uniaxial compression. Introducing tensile deformation in one direction can hamper this kind of pattern transformation under biaxial loading. For the soft solids with square lattices of voids, the number of voids cannot change their deformation behaviors qualitatively, but quantitatively. In general, our present results demonstrate that void morphology and biaxial loading can be harnessed to tune the pattern transformations of porous soft solids under large deformation. This discovery offers a new avenue for designing the void morphology of soft solids for controlling their deformation patterns under a specific biaxial stress-state.

Download Full-text

Stress Distribution Analysis of Different Types of Blade for a Fermentation System

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.479-480.319 ◽

2013 ◽

Vol 479-480 ◽

pp. 319-323

Author(s):

Cheng Chi Wang ◽

Po Jen Cheng ◽

Kuo Chi Liu

Keyword(s):

Stress Distribution ◽

Maximum Stress ◽

Effective Means ◽

Materials Processing ◽

Distribution Analysis ◽

Stress Distributions ◽

Fermentation System ◽

Different Types ◽

Inclined Angle ◽

Key Parameter

Fermentation system is widely used for food manufacturing, materials processing and chemical reaction etc. Different types of blade in the tank for fermentation cause distinct stress distributions on the surface between fluid and blade, and appear various flow fields in the tank. So, this paper is mainly focused on analyzing the stress field of blades under different scales of blade with fixing rotational speed. The results show that the ratio of blade length to width influences stress distribution on the blades. At the same time, the inclined angle of blade is also the key parameter for the consideration of design and appropriate design will decrease the maximum stress. The results provide an effective means of gaining insights into the stress distribution of fermentation system.

Download Full-text

Analysis of wave scattering in pipes with non-axisymmetric and inclined angle defects using finite element modeling

International Journal of Applied Mechanics ◽

10.1142/s1758825121500125 ◽

2021 ◽

Vol 13 (01) ◽

pp. 2150012

Author(s):

Masoud Masoumi ◽

Ryan K. Giles

Keyword(s):

Finite Element ◽

Wave Scattering ◽

Longitudinal Mode ◽

Elastic Wave Scattering ◽

Array Transducer ◽

Diameter Pipe ◽

Geometrical Shapes ◽

Identification Approach ◽

Sinusoidal Pattern ◽

Inclined Angle

In this paper, elastic wave scattering in hollow pipes with non-axisymmetric and inclined angle defects is studied using finite element (FE) simulations. A comb array transducer is employed in the FE code to excite the pipe in its first longitudinal mode using a 10-cycle sine modulated excitation signal at 120[Formula: see text]kHz central frequency. Defects with variations in geometrical shapes such as depths, axial and circumferential lengths, and inclined angles are investigated to provide detailed analysis of wave propagation patterns and mode conversions in a 12-in diameter pipe. The influence of each geometrical parameter and also possible newborn modes is studied both in time and wavenumber-frequency domain via circumferential order identification approach and dispersion curves. Results show that the depth of a non-axisymmetric circumferential defect has the minimum influence on the propagating mode while crack’s width can influence the measured longitudinal mode in a sinusoidal pattern which is a function of excitation signal’s wavelength. Further, the propagating mode can exhibit higher contribution of either axisymmetric or non-axisymmetric modes based on the reflection patterns, depending on its angle and axial length.

Download Full-text

Heat Transfer Enhancement in Triangular Ducts With an Array of Side-Entry Wall/Impinged Jets

Volume 3: Heat Transfer; Electric Power; Industrial and Cogeneration ◽

10.1115/99-gt-195 ◽

1999 ◽

Author(s):

J.-J. Hwang ◽

C.-S. Cheng ◽

Y.-P. Tsia

Keyword(s):

Heat Transfer ◽

Heat Transfer Enhancement ◽

Leading Edge ◽

Local Heat Transfer ◽

Local Heat ◽

Transfer Enhancement ◽

Transfer Coefficients ◽

Pressure Drops ◽

Heat Transfer Coefficients ◽

Inclined Angle

An experimental study has been performed to measure local heat transfer coefficients and static well pressure drops in leading-edge triangular ducts cooled by wall/impinged jets. Coolant provided by an array of equally spaced wall jets is aimed at the leading-edge apex and exits from the radial outlet. Detailed heat transfer coefficients are measured for the two walls forming the apex using transient liquid crystal technique. Secondary-flow structures are visualized to realize the mechanism of heat transfer enhancement by wall/impinged jets. Three right-triangular ducts of the same altitude and different apex angles of β = 30 deg (Duct A), 45 deg (Duct B) and 60 deg (Duct C) are tested for various jet Reynolds numbers (3000≦Rej≦12600) and jet spacings (s/d = 3.0 and 6.0). Results show that an increase in Rej increases the heat transfer on both walls. Local heat transfer on both walls gradually decreases downstream due to the crossflow effect. At the same Rej, the Duct C has the highest wall-averaged heat transfer because of the highest jet center velocity as well as the smallest jet inclined angle. Moreover, the distribution of static pressure drop based on the local through flow rate in the present triangular duct is similar to that that of developing straight pipe flows. Average jet Nusselt numbers on the both walls have been correlated with jet Reynolds number for three different duct shapes.

Download Full-text