• Journal of Welding and Joining
• /
• v.9 no.3
• /
• pp.41-51
• /
• 1991

The thermomechanical coupling phenomena in the resistance welding process is complicated due to interactions of mechanical, thermal and electrical factors. Although experimental investigations of resistance spot welding have been carried out, but there are a few by computer simulation. so the purpose of this research is to decrease the time and cost much required in experimental investigation by carrying out the analysis of the resistance spot welding process through computer simulation based on the finite element method. The tool used in the computer simulation is the commercial ANSYS program package. A two dimensional axisymetric model is used to simulate the resistance spot welding for two stainless steel sheets of equal thickness and parametric study is carried out for variable welding current, workpieces of unequal thickness and dissimilar materials. The results from the computer simulation are in good agreement with the experimental one. Through these results, such items as stress distribution, temperature profiles, thermal expansion and weld nugget formation are predicted. Reliability and applicability of finite element models have been demonstrated to simulate and to analyze the resistance spot welding process.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.9 no.3
• /
• pp.364-375
• /
• 1997

The fundamental theory and technical approach to aid design and development of an automotive air-conditioning system are presented. The evaluation methods for transient cooling load transferred to a passenger compartment and simulation of automotive air-conditioning components are outlined. The structure of the computer program, the experiemntal correlations, and the simulation results are also included. The total cooling load of the white-colored car is reduced upto 5% for that of the black-colored car when the car is running. Using the infrared reflectance glass, we can also obtain 5% reduction of the total cooling load for the common glass.

• Proceedings of the KSME Conference
• /
• 2000.04b
• /
• pp.19-24
• /
• 2000

The objective of this study is to develope a computer simulation model and estimate theoretically the transient performance characteristics of heat exchangers in an automotive air-conditioning system. To do that, the mathematical modelling of heat exchangers, such as evaporator and condenser, is presented first of all. For detail calculation, evaporator and condenser are divided into many sub-sections. Each sub-section is an elemental volume for transient modelling. The elemental volume is assumed to consist of three components, refrigerant, tube with fin, and air, and various properties including temperatures of three components are determined step along sub-sections. The properties of refrigerant R134a and air are calculated directly in the program. The heat transfer coefficients and pressure drop in single or two phase are also calculated by suitable empirical correlations. The overall tendencies of the simulation results were agreed well with those of actual situation.

• Journal of radiological science and technology
• /
• v.32 no.4
• /
• pp.445-451
• /
• 2009

The computed tomography(CT) simulation tool provides virtual experimental environment without using a high cost medical equipment. We made teaching materials for the CT simulation tools and educated the students and entry level of radio-technologists. We divided the experimental objects into two groups; students who took only theoretical classes (group 1) and students who took both theoretical and simulation classes (group 2). The results showed that the group 2 outperformed group 1 significantly, which indicates that the simulation program provides a good educational material for not only students but also radio-technologists.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.10 no.2
• /
• pp.202-216
• /
• 1998

A computer simulation for the performance analysis of automobile air conditioning components is carried out for the various operating conditions. The automobile air conditioning system consists of laminated type evaporator, swash plate type compressor, parallel flow type condenser, externally equalized thermostatic expansion valve and receiver drier. The overall heat transfer coefficient and the pressure drop in laminated type evaporator were obtained through experiments. In parallel flow type condenser, the performance analysis computer program using the empirical equation for heat transfer coefficient has been developed and the results are compared with experimental results. A model for matching the performance analysis programs of respective components .of automobile air conditioning system is introduced. Further, the effects of varying condenser size and refrigerant charge on the performance of automobile air conditioning system are discussed clearly.

• Journal of the Korean Society for Heat Treatment
• /
• v.2 no.2
• /
• pp.11-16
• /
• 1989

Understanding and control of thermal history of heat-treated components are very important in heat treating process. A computer program was developed for prediction of thermal history in quenching process with various cooling media and agitation conditions. Computer simulation of heat flow in quenching treatment of spur gear of SCM 22 H was carried out by two and three dimensional finite difference method. Distributions of microstructure and hardness in heat-treated spur gear were predicted by computer simulation, and the results showed a good agreement with the experiments. It was concluded that the

• Journal of the Korea Society of Computer and Information
• /
• v.27 no.1
• /
• pp.61-67
• /
• 2022

In this paper, we propose a model that can convert some of the simulation program resources to a mobile environment. Recently, smart factories that use PLCs as controllers in the manufacturing industry are rapidly becoming widespread. However, in the situation where it is difficult to operate due to the shortage of PLC operation personnel, the actual situation is that a platform for PLC operation education is necessary. Currently most PLC-related educational platforms are based on 2D, which makes accurate learning difficult and difficult. When a simulation program is applied to distance learning in a general PC environment, many elements are displayed on the monitor, which makes screen switching inconvenient. Experiments with the proposed model confirmed that there was no frame deterioration under general circumstances. The average response time by the request frame was 102 ms, and it was judged that the learner was not at the level of experiencing the system delay.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.6 no.4
• /
• pp.384-389
• /
• 1982

It is necessary that machine tool structures should be designed so that they will cause a minimum chance of machining chatter. In order to do this, a computer program package is developed utilizing Finite Element Method, modal flexibility and energy balance method. Validity of the program package is verified through computer simulation analysis and impulse test of a simplified machine tool structure.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
• /
• v.17 no.6
• /
• pp.686-695
• /
• 1988

An algorithm and a computer program were developed for the operational simulation of office building cooling system. Using this computer program, the following results were obtained. ${\bullet}$ There is a critical number of coil rows in AHU with which the cooling system can be operated in maximum efficiency. ${\bullet}$ Energy conservation can be achieved in an office building through TAB(Testing Adjusting and Balancing) of zone air volumes.

• The Journal of the Petrological Society of Korea
• /
• v.26 no.1
• /
• pp.93-98
• /
• 2017

In this paper, we propose a lava flow simulation program to predict the range of lava flows area and thickness of lava flows during volcanic eruptions. The map information is represented as a 'cell' with observed values per fixed area such as DEM and a lava flow prediction algorithm using a cellular automata model is performed to predict the flow of lava flows. To obtain quantitative data of lava flows, fluid properties of lava flows are defined as Bingham plastic fluid and derived equation is applied to the rules of cellular automata. To verify the program, we use a 30m resolution DEM provided by USGS. We compared simulation results with real lava flows for the Pu'u'O'o crater area in Hawaii, which has erupted since May 24, 2016.