Temperature Distribution in a Hollow Cylindrical Workpiece During Machining: Theoretical Model and Experimental Results

1991 ◽  
Vol 113 (4) ◽  
pp. 373-380 ◽  
Author(s):  
G. Subramani ◽  
M. C. Whitmore ◽  
S. G. Kapoor ◽  
R. E. DeVor

In this paper, an analytical model is developed for computation of the temperature distribution in a hollow cylindrical workpiece during machining with a single point tool. Such a model is useful for prediction of machined surface error arising from thermal expansion of the workpiece during machining. The model considers the interface between the tool and the workpiece to be a helically moving volumetric heat source. The governing equation satisfied by the temperature field, along with the appropriate boundary and initial conditions, is solved using the method of integral transforms. The experimental test facility used for the conduct of experiments for measurement of the temperature response in a cylindrical workpiece, namely a cylinder bore, during machining is discussed. The results from tests conducted using a laser as a heat source to verify the analytical model for temperature field are then presented. Several cylinder boring tests have been conducted, and the results from these tests along with the analysis performed with the temperature data to calibrate the temperature model are then discussed. Comparisons between predicted and measured temperature response in a cylinder bore during machining show good agreement.

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Yuhui Wu ◽  
Xinzhi Zhou ◽  
Li Zhao ◽  
Chenlong Dong ◽  
Hailin Wang

Acoustic tomography (AT), as a noninvasive temperature measurement method, can achieve temperature field measurement in harsh environments. In order to achieve the measurement of the temperature distribution in the furnace and improve the accuracy of AT reconstruction, a temperature field reconstruction algorithm based on the radial basis function (RBF) interpolation method optimized by the evaluation function (EF-RBFI for short) is proposed. Based on a small amount of temperature data obtained by the least square method (LSM), the RBF is used for interpolation. And, the functional relationship between the parameter of RBF and the root-mean-square (RMS) error of the reconstruction results is established in this paper, which serves as the objective function for the effect evaluation, so as to determine the optimal parameter of RBF. The detailed temperature description of the entire measured temperature field is finally established. Through the reconstruction of three different types of temperature fields provided by Dongfang Boiler Works, the results and error analysis show that the EF-RBFI algorithm can describe the temperature distribution information of the measured combustion area globally and is able to reconstruct the temperature field with high precision.


2021 ◽  
Author(s):  
Ninh The Nguyen ◽  
John H Chujutalli

Abstract FEA-based Gaussian density heat source models were developed to study the effect of convective and radiative heat sinks on the transient temperature field predicted by the available approximate analytical solution of the purely conduction-based Goldak’s heat source. A new complex 3D Gaussian heat source model, incorporating all three modes of heat transfer, i.e., conduction, convection and radiation, has been developed as an extension of the Goldak heat source. Its approximate transient analytical solutions for this 3-D moving heat source were derived and numerically benchmarked with the available measured temperature & weld pool geometry data by Matlab programming with ~5 to 6 times faster than FEA-based simulation. The new complex 3D Gaussian heat source model and its approximate solution could significantly reduce the computing time in generating the transient temperature field and become an efficient alternative to extensive FEA-based simulations of heating sequences, where virtual optimisation of a melting heat source (i.e. used in welding, heating, cutting or other advanced manufacturing processes) is desirable for characterisation of material behaviour in microstructure evolution, melted pool, microhardness, residual stress and distortions.


2019 ◽  
Vol 2019 ◽  
pp. 1-13 ◽  
Author(s):  
Jerzy Winczek ◽  
Marek Gucwa ◽  
Miloš Mičian ◽  
Krzysztof Makles

In the work, an analysis of the influence of electrode inclination on the distribution of temperature in the weld overlaying has been conducted. In the analytical description of the temperature field, a volumetric heat source model with an inclined axis with respect to the direction of surfacing was adopted. In the numerical simulation, the own theoretical model of heat source, algorithm, and program performed in the Borland Delphi environment were used. In the calculation examples, different electrode inclination angles were adopted in relation to the welded plate, in the direction of surfacing, opposite to the direction of welding, and perpendicular to the weld bead.


Materials ◽  
2019 ◽  
Vol 12 (7) ◽  
pp. 1032 ◽  
Author(s):  
Jae-Hyeon Ha ◽  
Choon-Man Lee

Thermally assisted machining (TAM) is an effective method for difficult-to-cut materials, and works by locally preheating the workpiece using various heat sources, such as laser, induction, and plasma. Recently, many researchers have studied TAM because of its low manufacturing costs, high productivity, and quality of materials. Laser assisted machining (LAM) has been studied by many researchers, but studies on TAM using induction or plasma heat sources, which are much cheaper than lasers, have been carried out by only a few researchers. Lasers have an excellent preheating effect, but are expensive, and the temperature of the heated workpiece drops quickly. Here, multi heat sources were used to solve the shortage in supplied heat source with a single heat source. Induction was applied as an additional heat source. The purpose of this study is to analyze the thermal effect and temperature distribution of single heat source and multi heat sources, and compare the machining characteristics according to heat source types. In order to analyze the preheating effect according to the feed rate of the heat sources, a temperature measurement experiment using thermocouples was carried out, and the efficiency of the thermal effect using multi heat sources was verified. In addition, the effectiveness of the thermal analysis results was verified by comparison with the measured temperature distribution. The machining characteristics of Inconel 718 and Ti-6Al-4V with laser, induction, and laser-induction assisted milling (LIAMill) were analyzed, by cutting force and surface roughness.


2012 ◽  
Vol 542-543 ◽  
pp. 1120-1123
Author(s):  
Chuan Zhi Mei ◽  
Lin Hua Piao ◽  
Quan Gang Yu ◽  
Bao Li Zhang ◽  
Xia Ding ◽  
...  

In this paper, the pendulum characteristic of nature convection gas in dimensional enclosure is analyzed by FEM. Using ANSYS-FLOTRAN CFD program, the stream field and the temperature field caused by the point heat source, when the two-dimensional enclosure is inclined, has been obtained by a series of procedure, such as model building, meshing, loads applying and equation solving. The results are as follow: (1)Under the buoyancy lift affecting, the direction of nature convection gas always keeps the vertical upward in two-dimensional enclosure, nature convection gas has the pendulum characteristic. (2)When the dimensional enclosure is inclined, temperature distribution at the several points in dimensional enclosure will change with the tilt angle. The pendulum characteristic can be utilized to measure the tilt angle by the gas pendulum tilt sensor.


2010 ◽  
Vol 426-427 ◽  
pp. 89-92
Author(s):  
Hong Feng Wang ◽  
Dun Wen Zuo ◽  
Ming Min Huang ◽  
Hong Miao

From the laser welding actual process, the welding heat source model of laser welding process was established, that is, superposition heat source. According to the knowledge of thermodynamics, the establishment of a welding process, the mathematical model of temperature distribution of laser welding process was obtained by laser welding heat source. Finally, the finite element simulation of welding temperature distribution was used. The simulated results were compared with the analytical results of mathematical model of temperature field, it was proved consistent between simulated results and analytical results, at the same time it can account for the correctness of the mathematical model of temperature field.


1975 ◽  
Vol 97 (1) ◽  
pp. 39-44
Author(s):  
C. S. Kang ◽  
Y. P. Chang

This paper presents a numerical method for the solution of problems of moving heat sources with change of phase and with any boundary condition. Calculated results of two specific cases are shown: one for a plane moving source in a rod and the other for a line source in a plate. It is found that for low heat input and/or low initial temperature, the change of phase does not affect significantly the temperature distribution in the medium, were it of solid only. However, the higher the heat input and/or the initial temperature, the larger is the effect of phase-change to the temperature field.


2014 ◽  
Vol 919-921 ◽  
pp. 313-317
Author(s):  
Li Wei Zhang ◽  
Ming Ji Wang ◽  
Wen Cao

Acoustic thermometry method is used to measure two-dimensional temperature distribution of a circular boundary temperature field experimentally. The measured temperature field is compared with a point-by-point temperature measurement, the results shows that the acoustic method is consistent with the point-by-point measurement which proves that it is reliable to use this method to measure the two-dimensional temperature distribution.


2001 ◽  
Author(s):  
Jiuhui Wu ◽  
Hualing Chen

Abstract A non-linear wave equation in a nonuniform sound space is deduced to determine the coupling relation between sound field and temperature field. Adopting Poisson’s integral a formula for calculating the interior sound field with uneven temperature field and certain initial conditions is developed. This establishes the corresponding theoretical foundation for studying the heat and vibroacoustic comfortability in a vehicle passenger room.


Sign in / Sign up

Export Citation Format

Share Document