Secondary Development of ANSYS Software to Calculating Sunshine Temperature Stress of Hollow Pier

2011 ◽  
Vol 255-260 ◽  
pp. 1906-1909
Author(s):  
Jun Ying Ge

For hollow but high bridge piers, single side sun exposure causes great temperature stress. Currently, the bridge specifications of each countries have different regulations on hollow pier’s temperature load, partly can only reference to the temperature gradient curve of box girders, but the errors might be large sometimes. This paper gives a method to calculate the hollow pier’s temperature field and stress that caused by solar radiation, a method which can consider any region, any season and any time. A secondary development is also applied to reinforce ANSYS software, and the aforementioned functions is embedded in the ANSYS GUI.

2011 ◽  
Vol 255-260 ◽  
pp. 3539-3542
Author(s):  
Pan Wu Li ◽  
Jia Ming Gao ◽  
Xian Zhe Zeng

The heat(cold) caused by atmospheric temperature flows backward during construction period makes the temperature field and the stress field of concrete change a lot, and we have to take relevant measures when the change influence the crack resistance of concrete. Based on the causes and the change-principium of thermal stress, we use ANSYS software to analyze the influence on temperature field and the stress field of concrete that caused by atmospheric temperature, and find some measures to protect the concrete from excessive temperature stress.


Energies ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1792
Author(s):  
Bingbing Dong ◽  
Yu Gu ◽  
Changsheng Gao ◽  
Zhu Zhang ◽  
Tao Wen ◽  
...  

In recent years, the new type design of current transformer with bushing structure has been widely used in the distribution network system due to its advantages of miniaturization, high mechanical strength, maintenance-free, safety and environmental protection. The internal temperature field distribution is an important characteristic parameter to characterize the thermal insulation and aging performance of the transformer, and the internal temperature field distribution is mainly derived from the joule heat generated by the primary side guide rod after flowing through the current. Since the electric environment is a transient field and the thermal environment changes slowly with time as a steady field under the actual conditions, it is more complex and necessary to study the electrothermal coupling field of current transformer (CT). In this paper, a 3D simulation model of a new type design of current transformer for distribution network based on electric-thermal coupling is established by using finite element method (FEM) software. Considering that the actual thermal conduction process of CT is mainly by conduction, convection and radiation, three different kinds of boundary conditions such as solid heat transfer boundary condition, heat convection boundary condition and surface radiation boundary condition are applied to the CT. Through the model created above, the temperature rise process and the distribution characteristics of temperature gradient of the inner conductor under different current, different ambient temperatures and different core diameters conditions are studied. Meanwhile, the hottest temperature and the maximum temperature gradient difference are calculated. According to this, the position of weak insulation of the transformer is determined. The research results can provide a reference for the factory production of new type design of current transformer.


2011 ◽  
Vol 199-200 ◽  
pp. 1492-1495 ◽  
Author(s):  
Guo Shun Wang ◽  
Rong Fu ◽  
Liang Zhao

The simulation calculation on the temperature field of the disc brake system on high-speed trains under the working condition of constant speed at 50Km/h is made. A steady-state calculation model is established according to the actual geometric size of a brake disc and a brake pad, and the analog calculation and simulation on the temperature field of the brake disc and the brake pad by using the large-scale nonlinear finite element software ABAQUS are carried out. The distribution rules of the temperature field of the brake disc and the brake pad under the working condition of constant speed are made known. The surface temperature of the brake disc at friction radius is the highest, with a band distribution for temperature. There exists a temperature flex point in the direction of thickness, of which the thickness occupies 15% of that of the brake disc; due to the small volume of the brake pad, the temperature gradient of the whole brake pad is not sharp, and larger temperature gradient occurs only on the contact surface.


2011 ◽  
Vol 2-3 ◽  
pp. 856-860
Author(s):  
Chang Li ◽  
Guang Bing Zhao ◽  
Shu Yu Zhang ◽  
Xing Han

Cast molding is the main manufacture process in foundry, because the most disfigurements occurs in this step, while the foundry itself is a complex non-linear instantaneous transferring heat process, in which it should take the absorbing and releasing potential heat into account. In this paper, it simulates the temperature field changing process of the cast solidification in ANSYS software, gets the temperature field change rule for a typical cast, and analyzed the effect of different foundry technics parameters on composite interface temperature, which will provide numerical bases for optimizing foundry technics parameters in future.


2014 ◽  
Vol 1065-1069 ◽  
pp. 882-888
Author(s):  
Yue Huang ◽  
Xing Fa Wu

In the approach spans of Quanzhou Bay Cross-sea Bridge, these standard spans are 50m or 70m , width is 20.05m.The approach spans have been built by using short Line segments precast and erection method. This is the first application in the cross sea bridges. According to characteristics of this project, the research on prefabrication and erection technology of wide box girders has been carried out to solve the technical problems in the process of construction. The research show that: 1)In precasting process , the vertical deformation of wide box girder is very small under dead load and temperature load etc. so the influence of prefabrication and erection accuracy can be ignored; 2)The temporary anchor using prestressed steel strand better than planished steel; 3) When using epoxy gasket to adjust geometric line shape, the thickness of cemented layer has a great influence on the linear adjustment;4)The epoxy gasket and bridge erecting machine should be used together, Alignment adjustmen could obtain satisfactory results.


2017 ◽  
Vol 835 ◽  
pp. 170-216 ◽  
Author(s):  
Sayan Das ◽  
Shubhadeep Mandal ◽  
Suman Chakraborty

The motion of a viscous droplet in unbounded Poiseuille flow under the combined influence of bulk-insoluble surfactant and linearly varying temperature field aligned in the direction of imposed flow is studied analytically. Neglecting fluid inertia, thermal convection and shape deformation, asymptotic analysis is performed to obtain the velocity of a force-free surfactant-laden droplet. The droplet speed and direction of motion are strongly influenced by the interfacial transport of surfactant, which is governed by surface Péclet number. The present study is focused on the following two limiting situations of surfactant transport: (i) surface-diffusion-dominated surfactant transport considering small surface Péclet number, and (ii) surface-convection-dominated surfactant transport considering high surface Péclet number. Thermocapillary-induced Marangoni stress, the strength of which relative to viscous stress is represented by the thermal Marangoni number, has a strong influence on the distribution of surfactant on the droplet surface. The present study shows that the motion of a surfactant-laden droplet in the combined presence of temperature and imposed Poiseuille flow cannot be obtained by a simple superposition of the following two independent results: migration of a surfactant-free droplet in a temperature gradient, and the motion of a surfactant-laden droplet in a Poiseuille flow. The temperature field not only affects the axial velocity of the droplet, but also has a non-trivial effect on the cross-stream velocity of the droplet in spite of the fact that the temperature gradient is aligned with the Poiseuille flow direction. When the imposed temperature increases in the direction of the Poiseuille flow, the droplet migrates towards the flow centreline. The magnitude of both axial and cross-stream velocity components increases with the thermal Marangoni number. However, when the imposed temperature decreases in the direction of the Poiseuille flow, the magnitude of both axial and cross-stream velocity components may increase or decrease with the thermal Marangoni number. Most interestingly, the droplet moves either towards the flow centreline or away from it. The present study shows a critical value of the thermal Marangoni number beyond which the droplet moves away from the flow centreline which is in sharp contrast to the motion of a surfactant-laden droplet in isothermal flow, for which the droplet always moves towards the flow centreline. Interestingly, we show that the above picture may become significantly altered in the case where the droplet is not a neutrally buoyant one. When the droplet is less dense than the suspending medium, the presence of gravity in the direction of the Poiseuille flow can lead to cross-stream motion of the droplet away from the flow centreline even when the temperature increases in the direction of the Poiseuille flow. These results may bear far-reaching consequences in various emulsification techniques in microfluidic devices, as well as in biomolecule synthesis, vesicle dynamics, single-cell analysis and nanoparticle synthesis.


2017 ◽  
Vol 898 ◽  
pp. 422-429 ◽  
Author(s):  
Wei Guo Zhang ◽  
Zhi Jie Liu ◽  
Song Ke Feng ◽  
Fu Zeng Yang ◽  
Lin Liu

The stress rupture life of DZ125 nickel-based superalloy that was prepared by directional solidification process under the temperature gradient of 500 K/cm has been studied at 900°C and 235MPa. The results showed that with the increase of directional solidification rate from 50 μm/s to 800 μm/s, the primary dendrite arm spacing reduced from 94 μm to 35.8 μm and γ' precipitates reduced and more uniformed in size. The high temperature stress rupture life of as-cast sample increased firstly and then decreased and reached its maximum at the solidification rate of 500 μm/s. The dislocation configuration of sample with refine dendritic structure after stress rupture was investigated and discovered that the dislocations in different parts of sample had different morphology and density, which indicated that the deformation of as-cast samples were uneven during high temperature stress rupture. A lot of dislocations intertwined around carbides and at the interface of γ/γ', and the dislocation networks were destroyed and the dislocations entered γ' precipitate by the way of cutting.


2010 ◽  
Vol 3 (5) ◽  
pp. 1487-1507 ◽  
Author(s):  
M. Kiefer ◽  
E. Arnone ◽  
A. Dudhia ◽  
M. Carlotti ◽  
E. Castelli ◽  
...  

Abstract. We examine volume mixing ratios (vmr) retrieved from limb emission spectra recorded with the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) on board Envisat. In level 2 (L2) data products of three different retrieval processors, which perform one dimensional (1-D) retrievals, we find significant differences between species' profiles from ascending and descending orbit parts. The relative differences vary systematically with time of the year, latitude, and altitude. In the lower stratosphere their monthly means can reach maxima of 20% for CFC-11, CFC-12, HNO3, H2O, 10% for CH4 and N2O. Relative differences between monthly means of 1-D retrieval results and of the true atmospheric state can be expected to reach half of these percentage values, while relative differences in single vmr profiles might well exceed those numbers. Often there are no physical or chemical reasons for these differences, so they are an indicator for a problem in the data processing. The differences are generally largest at locations where the meridional temperature gradient of the atmosphere is strong. On the contrary, when performing the retrieval with a tomographic two dimensional (2-D) retrieval, L2 products generally do not show these differences. This suggests that inhomogeneities in the temperature field, and possibly in the species' fields, which are accounted for in the 2-D algorithm and not in standard 1-D processors, may cause significant deviations in the results. Inclusion of an externally given adequate temperature gradient in the forward model of a 1-D processor helps to reduce the observed differences. However, only the full tomographic 2-D approach is suitable to resolve the horizontal inhomogeneities. Implications for the use of the 1-D data, e.g. for validation, are discussed. The dependence of the ascending/descending differences on the observation strategy suggests that this problem may affect 1-D retrievals of infrared limb sounders, if the line of sight of the instrument has a significant component in the direction of the horizontal temperature variation.


2006 ◽  
Vol 2 (S239) ◽  
pp. 513-513
Author(s):  
D. Skandera ◽  
W.-Ch. Müller

AbstractSpectral properties of convective magnetohydrodynamic (MHD) turbulence in two and three dimensions are studied by means of direct numerical simulations (Skandera D. & Müller W.-C. 2006). The investigated system is set up with a mean horizontal temperature gradient in order to avoid a development of elevator instabilities in a fully periodic box. All simulations are performed without mean magnetic field. The applied resolution is 5123 and 20482. The MHD equation are solved by a numerical code (Müller & Biskamp 2000) that uses a standard pseudospectral scheme. For removing of aliasing errors a spherical truncation method is employed. Obtained results are compared with predictions of various existing phenomenological theories for magnetohydrodynamic and convective turbulence (Müller & Biskamp 2000). While the three-dimensional system is found to operate in a Kolmogorov-like regime where buoyant forces have a negligible impact on the turbulence dynamics (relatively low Rayleigh number achieved in the simulation; Ra ∼106), the two-dimensional system exhibits interesting irregular quasi-oscillations between a buoyancy dominated Bolgiano-Obukhov-like regime of turbulence and a standard Iroshnikov-Kraichnan-like regime of turbulence (Müller & Biskamp 2000). The most important parameter determining the turbulent regime of 2D magnetoconvection, apart from a high Rayleigh number, seems to be the mutual alignment of velocity and magnetic fields. The non-linear dynamics and the interplay between individual fields are examined with different transfer functions that confirm basic assumptions about directions of energy transfer in spectral space. Kinetic, magnetic and temperature energy are transported by a turbulent cascade from large to smaller scales. The local/nonlocal character of the transport is tested for several individual terms in the governing equations. Moreover, other statistical quantities, e.g. probability density functions, are computed as well. A passive character of the temperature field in the investigated three-dimensional magnetoconvection is supported by computations of intermittency using extended self-similarity. The intermittency of the Elsasser field z+ is in agreement with results from numerical simulations of isotropic MHD turbulence (Müller & Biskamp 2000). The intermittency of the temperature field is found to approximately agree with results of passive scalar measurements in hydrodynamic turbulence (Ruiz-Chavarria, Baudet & Ciliberto 1996).


1988 ◽  
Vol 110 (3) ◽  
pp. 254-256 ◽  
Author(s):  
E. H. Wissler

Presented in this paper is a solution for countercurrent heat exchange between two parallel vessels embedded in an infinite medium with a linear temperature gradient along the axes of the vessels. The velocity profile within the vessel is assumed to be parabolic. This solution describes the temperature field within the vessels, as well as in the tissue, and establishes that the intravessel temperature is not uniform, as is generally assumed to be the case. An explicit expression for the intervessel thermal resistance based on the difference between cup-mixed mean temperatures is derived.


Sign in / Sign up

Export Citation Format

Share Document