Plastic Flow at the Chip-Tool Interface During Hot Machining

1971 ◽  
Vol 93 (2) ◽  
pp. 437-440 ◽  
Author(s):  
B. Bhattacharyya ◽  
R. F. Scrutton
Keyword(s):  
Temperature Distribution ◽  
Physical Properties ◽  
Electric Current ◽  
Plastic Flow ◽  
Joule Heating ◽  
Plastic Layer ◽  
Hot Machining

The plastic flow of metal adjacent to the chip-tool interface when machining heated workpieces is examined theoretically. It is shown that all metallic workpiece materials possess an optimum machining temperature which is dependent on the physical properties of the material. The temperature distribution in the plastic layer in the presence of an electric current normal to the interface is considered in relation to the general plastic flow of metals accompanied by Joule heating.

Coupled Electro-Thermal Mechanical Analyses for SMM Actuators Development

2004 ◽  
Author(s):  
C. Channy Wong ◽  
Randy R. Lober ◽  
Jason D. Hales
Keyword(s):  
Electrical Resistivity ◽  
Temperature Distribution ◽  
Joule Heating ◽  
Temperature Dependent ◽  
Strongly Coupled ◽  
Mechanical Responses ◽  
Thermal Actuators ◽  
Micro Actuators ◽  
And Performance

A coupled-physics analysis code has been developed to simulate the electrical, thermal, and mechanical responses of surface micromachined (SMM) actuators. Our objective is to optimize the design and performance of these micro actuators. Since many new designs of these electro-thermal actuators have shuttles or platforms between beams, calculating the local Joule heating requires a multi-dimensional electrostatics analysis. Moreover, the electrical solution is strongly coupled to the temperature distribution since the electrical resistivity is temperature dependent. Thus, it is essential to perform a more comprehensive simulation that solves the coupled electrostatics, thermal, and mechanical equations. Results of the coupled-physics analyses will be presented.

Multi-Cell Concept for Simulating Fires in Big Enclosures Using a Zone Model

1996 ◽  
Vol 14 (3) ◽  
pp. 186-198 ◽  
Author(s):  
W.K. Chow
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Temperature Distribution ◽  
Physical Properties ◽  
Flow Pattern ◽  
Layer Thickness ◽  
Zone Model ◽  
Smoke Layer

The multi-cell concept is applied to simulate fire in a big com partment with the zone model CFAST. The predicted physical properties of the smoke layer are used to justify the results, including the smoke layer tempera ture, smoke layer thickness and flows between each cell. Microscopic pictures of the flow pattern and smoke temperature distribution similar to the results pre dicted by the Computational Fluid Dynamics technique can be obtained. This idea is recommended to study fires in big enclosures.

scholarly journals Nonlocal Problems Arising in Thermoelectrics

2014 ◽  
Vol 2014 ◽  
pp. 1-7
Author(s):  
Jaywan Chung ◽  
Byungki Ryu
Keyword(s):  
Power Generation ◽  
Temperature Distribution ◽  
Electric Current ◽  
Nonlocal Problem ◽  
Thermoelectric Effect ◽  
Nonlocal Problems ◽  
Diffusion Term

We revisit the derivation of a nonlocal problem modelling temperature distribution due to power generation using thermoelectric effect. The problem has nonlocal coefficients in reaction and convection terms rather than diffusion term, which makes the problem more interesting. In this paper, we prove that the nonlocal problem has a unique decreasing solution when electric current induced by the thermoelectric effect is small enough.

Change in temperature distribution by constriction of electric current through contact area

2015 ◽  
Vol 20 (4) ◽  
pp. 337-344
Author(s):  
K. Wakabayashi ◽  
P. Hemthavy ◽  
S. Saito ◽  
K. Takahashi
Keyword(s):  
Temperature Distribution ◽  
Electric Current ◽  
Contact Area

scholarly journals Uji Kinerja Alat Penyangrai Kopi Tipe Silinder Menggunakan Band-Heater sebagai Pemanas

2020 ◽  
Vol 4 (4) ◽  
pp. 382-391
Author(s):  
Gamal Abdil Nasir ◽  
Syafriandi Syafriandi ◽  
Mustaqimah Mustaqimah
Keyword(s):  
Temperature Distribution ◽  
Data Collection ◽  
Water Content ◽  
Electric Power ◽  
Electric Current ◽  
Electrical Power ◽  
Coffee Consumption ◽  
Electrical Energy ◽  
Analysis Data ◽  
Heat Element

Abstrak. Konsumsi kopi di Indonesia mengalami kenaikan rata-rata sekitar 3 % setiap tahunnya. Meningkatnya nilai konsumsi kopi menjadi pendorong bagi pelaku pengolahan kopi untuk meningkatkan produksinya. Oleh karena itu penting untuk memiliki alat penyangrai yang dapat meningkatkan kualitas dan kuantitas produksi. Penelitian ini dilakukan pengujian mesin sangrai tipe silinder yang dilengkapi elemen panas (heater) sebagai pemanas dan diharapkan dapat mempercepat proses penyangraian dengan kadar air sangrai yang lebih seragam.Tujuan penelitian adalah untuk mengetahui kinerja mesin sangrai kopi tipe silinder menggunakan elemen panas (heater) untuk penyangraian kopi robusta sebanyak 2 kg/penyangraian.Prosedur penelitian dimulai dengan persiapan alat, pengumpulan data dan analisa data. Pengumpulan data dilakukan dengan metode observasi. Pengamatan dan analisis data meliputi distribusi suhu, kadar air, kuat arus listrik, daya listrik dan kebutuhan energi listrik.Hasil penelitian menunjukan penyangraian dilakukan pada tingkat menengah (medium), nilai distribusi suhu yang dihasilkan berbeda, sesuai jumlah heater yang digunakan. Heater 7, suhu berkisar 70-85 °C dengan kadar air kopi sangrai 2.2 % sementara suhu sangrai 9 Heater, berada di 98.33-114 °C kadar air 1.37 % dengan tingkat kematangan yang relatif beragam. Daya listrik yang diperlukan untuk menjalankan semua elemen panas pada penyangraian dengan 7 heater yaitu 2160.56 watt dengan kuat arus yang diperlukan 9.95 ampere, daya listrik sangrai dengan 9 heater 2726.74 watt arus listrik yang dibutuhkan 12.71 ampere.Test the Performance of Coffee Roasters by Using a Heat Element as a Heat SourceAbstract. Coffee consumption in Indonesia has increased an average of around 3% every year. The increasing value of coffee consumption is driving the coffee processing industry to increase its production. Therefore it is important to have a roaster that can improve the quality and quantity of production. This research is carried out testing a cylindrical type roaster machine equipped with a heating element (heater) as a heater and is expected to accelerate the roasting process with a more uniform roasting water content.The purpose of this study was to determine the performance of a cylindrical type coffee roaster machine using a heat element (heater) for roasting robusta coffee of 2 kg / roasting. The research procedure begins with the preparation of tools, data collection and data analysis. Data collection is done by observation method. Data observations and analyzes include temperature distribution, water content, electric current strength, electric power and electrical energy requirements.The results showed that roasting was done at the medium level (medium), the resulting temperature distribution values were different, according to the number of heaters used. Heater 7, the temperature ranges from 70-85 ° C with 2.2% roasted coffee water content while the temperature of the roasted 9 Heater, is at 98.33-114 ° C the water content is 1.37% with a relatively diverse level of maturity. The electric power needed to run all the heat elements in roasting with 7 heaters is 2160.56 watts with the required strong current of 9.95 amperes, roasted electrical power with 9 heaters 2726.74 watts of electric current required 12.71 amperes.

Thermal Stresses Induced into Two Plane Strain Sectors Having Different Material Properties

1977 ◽  
Vol 99 (1) ◽  
pp. 26-30
Author(s):  
I-Chih Wang ◽  
J. P. Eimermacher
Keyword(s):  
Temperature Distribution ◽  
Physical Properties ◽  
Plane Strain ◽  
Material Properties ◽  
Thermal Stresses ◽  
Structural Characteristics ◽  
Uniform Temperature ◽  
General Application ◽  
Numerical Examples ◽  
Stress Functions

Thermal stresses induced into two joined plane strain sectors having different physical properties and subjected to a uniform temperature distribution are investigated. Considering the elastic equations of equilibrium, compatibility, the stress-strain equations and appropriate boundary conditions, airy stress functions are formulated which describe the structural characteristics of the sectors. Stress and displacement relations are then obtained. Numerical examples are given illustrating the usage and general application of the derived expressions.

scholarly journals VI. The influence of stress and strain on the physical properties of matter. Part I. Elasticity— continued . The effect of magnetisation on the elasticity and the internal friction of metals

1886 ◽  
Vol 40 (242-245) ◽  
pp. 447-449 ◽  
Keyword(s):  
Internal Friction ◽  
Physical Properties ◽  
Electric Current ◽  
Stress And Strain ◽  
The Wire ◽  
Permanent Rotation ◽  
A Current

The principal object of this investigation was to test the soundness of the view advanced by Professor G. Wiedemann respecting the cause of the internal friction of a torsionally oscillating wire. According to this view the internal friction is mainly due to permanent rotation to-and-fro of the molecules about their axes; it seemed probable, therefore, that experiments on the effects of magnetising a wire either longitudinally with a helix or circularly by passing a current through it would aid in elucidating the matter. In the experiments on the effects of longitudinal magnetisation arrangements were made so that the heat generated in the magnetising helix should not reach the wire, whilst the effect of the heat generated in the wire when an electric current was passed through it was eliminated in a manner which is fully described in the paper.

In situ scanning electron microscopy observations of filler material transport in branched carbon microtubes by Joule heating

Microscopy ◽  
2020 ◽  
Vol 69 (5) ◽  
pp. 291-297
Author(s):  
Masaki Okada ◽  
Daiya Sasaki ◽  
Hideo Kohno
Keyword(s):  
Electron Microscopy ◽  
Electric Current ◽  
Joule Heating ◽  
Volume Expansion ◽  
Filler Material ◽  
Material Transport ◽  
Metal Filler ◽  
Thermal Volume Expansion ◽  
Scanning Electron

Abstract Y-branched or side-by-side-branched carbon microtubes with metal filler material were fabricated, and material transport in the branched microtubes with Joule heating was investigated using in situ scanning electron microscopy with micro-electrode probes. When a voltage and electric current were applied, the material enclosed in the microtubes moved from its original position. The movement was not related to the direction of the electric current; therefore, it is concluded that the movement was not due to electromigration, but rather a temperature gradient, volume expansion and increased vapor pressure by Joule heating. In Y-branched microtubes, a part of the metal filler material moved from one branch to another branch, which would be useful for microfluidic flow switching. A cylindrical filler material was also observed to be expelled from a branch while its shape was maintained, and this phenomenon is presumably caused by vaporization-induced high pressure and could find application in micro-mechanical manipulators such as punching needles. In side-by-side-branched carbon microtubes, Joule heating caused thermal volume expansion to fill the spaces in the branches that were initially empty. The microtubes then reverted to a state almost identical to the initial state with empty spaces when the electric current was turned off. These results suggest that thermal volume expansion could be employed for flow switching.

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