• Journal of Advanced Marine Engineering and Technology
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• v.25 no.2
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• pp.331-337
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• 2001

A numerical simulation of the temperature rise for sliding surface in dry contact is based on Jaegers formula combined with a calculated heat input. A gear tooth temperature analysis was performed. The pressure distribution has the Hertzian pressure distribution on the heat source. The heat partition factor is calculated along ling of action. A Temperature distribution of tooth surface is calculated about before and after profile modification. A Temperature of addendum and deddendum in modified gear have reduced.

• Tribology and Lubricants
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• v.18 no.6
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• pp.389-395
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• 2002

The surface temperature at the interface of bodies in a sliding contact is one of the most important factors influencing the behavior of machine components. The calculation of the surface temperature at a sliding contact interface has been an interesting and important subject for tribologist. Temperature analyses were usually performed under the consideration contacted two bodies as semi-infinite. But the analysis was difficulty in being applied to finite body and considering the boundary condition. In this study, contact temperature rise of two finite bodies and surfaces due to frictional heating under the rectangular and the circular sliding contact is calculated. Heat partition factor is calculated using semi-infinite solid analysis and the temperature of the finite bodies is calculated using FVM. It will be shown that Most frictional heat in the fore part of contact region for sliding direction is conducted into body that has a moving heat source and the site of the maximum temperature rise moves to the opposite direction of sliding during sliding.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2000.06a
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• pp.251-257
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• 2000

A numerical simulation of the temperature rise for sliding surface in dry contact is based on Jaeger's formula combined with a calculated heat input. A gear tooth temperature analysis was performed. The pressure distribution has the Hertzian pressure distribution on the heat source. The heat partition factor is calculated along line of action. A Temperature distribution of tooth surface is calculated about before and after profile modification. A Temperature of addendum and deddendum in modified gear have reduced.

• KSTLE International Journal
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• v.1 no.1
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• pp.63-68
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• 2000

Angular contact ball bearings are mainly used in the spindle, which requires high speed and stiffness. The heat generation is studied by experiments and simulations using a pair of angular contact ball bearings. The temperature variation of inner and outer races and the temperature increment distribution are measured by using thermocouples for the rotational speed, preload, viscosity of lubricant. The measured values from experiments are used to estimate the heat conduction rate. The method of oil-air lubrication is used for the experiment. The amount of conduction heat transfer to the test spindle and the convection heat transfer coefficients long the spindle are computed by using inverse method with temperature increment distribution. Total heat generation rate is estimated with the heat partition rate which is calculated from temperatures of inner and outer races. In addition, the empirical factor of oil-air lubrication method for Palmgren's heat generation model is suggested. The empirical friction coefficients, which are obtained from the experiments, depend on the preload condition, and can give us more accurate estimation of the heat generation in ball bearings.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2003.11a
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• pp.97-104
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• 2003

The surface temperature at the interface of bodies in a sliding contact is one of the most important factors influencing the behavior of machine components. So the calculation of the surface temperature at a sliding contact interface has long been an interesting and important subject for tribologist. In this study to verify estimation of temperature rising, calculated temperatures were compared with measured temperatures. It is possible to calculate bulk and flash temperature.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2001.11a
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• pp.260-266
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• 2001

The surface temperature at the interface of bodies in a sliding contact is one of the most important factors influencing the behavior of machine components. So the calculation of the surface temperature at a sliding contact interface has long been an interesting and important subject for tribologist. Several methods for calculating surface temperature have been devised. Several numerical methods have been used to predict the temperature rise of sliding surface. but those need much time to calculate. In this study to reduce the calculation time the hybrid method using both semi-infinite solid analysis and FVM was used. It is founded that the computing time of hybrid method was shorter than that of FVM.

• Fire Science and Engineering
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• v.22 no.1
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• pp.128-138
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• 2008

Lots of products stocked at a traditional market are made of rubbers, synthetic fibers and plastics which when on fire, emit high heat to easily ignite nearby inflammables. And shops are not divided by fireproof partitions but by combustible curtains, which contributes to a possibility of a conflagration. In this study, danger and weak factors on fire at a traditional market was analyzed. Non-existence of partition between shops and the height of piled inflammables are set as danger factors and change of extinguishing capacity of sprinklers was analyzed using fire dynamics simulator. As a result, it turned out that partitions between shops and high-piled inflammables reduced watering radius of sprinklers and increased the size of fire and distribution of temperature.