In this study, gas flow pattern and temperature distribution in a laboratory scale low temperature furnace for carbonization were numerically analyzed. The furnace was designed for testing carbonization process of carbon fibers made from polyimide(PI) precursor. Nitrogen gas was used as a working gas and it was treated as an ideal gas. Three-dimensional computational fluid dynamics analysis for steady state turbulent flow was used to analyze flow pattern and temperature field in the furnace. The results showed that more uniform velocity profile and axisymmetric temperature distribution could be obtained by varying mass flow rate at the inlets.

The SMC(Sheet molding compound) process is widely used in the automotive industry to produce parts that are large, thin, lightweight, strong and stiff. Compression molded parts are formed by squeezing a glass fiber reinforced UP(Unsaturated Polyester) sheet, known as sheet mold compound(SMC), between two heated cavity surfaces. This paper has performed flow analysis to predict optimization process of low density SMC. After five types of design variables and six types of response variables were defined, DOE(Design of Experiment) and RSM (Response Surface Method) were applied in order to measure sensitivity of design variables and realize optimization through regression model. After design optimization, the total warpage of the SMC is reduced by about 12% compared to the initial design of SMC and cure time, cure temperature, clamping force and flow pressure are decreased by 0.6∼27% in comparison with the initial design. By doing this, the production costs could be diminished.

본 연구는 물리적인 방법을 이용하여 설계갈수량을 추정할 수 있는 방법을 제안한 것이다. 가뭄기간과 갈수유출사상이 상사하다는 전제하에 재현기간을 감수시간으로 변환 할 수 있는 모형을 유도하였다. 또 계측지점이나 미계측지점에 적용할 수 있는 감수모형을 제안했다. 본 감수시간 모형의 매개변수는 기후조건치, 유역특성치, 유출특성치 등이고 감수모형의 매개변수는 초기유량, 감수상수이다. 본 모형을 용담수위표 지점과 다른 임시관측 지점에 적용해 본 결과 유량관측 기

A Numerical simulation on the thermal flow performance was carried out to propose the incinerator type for the domestic refuses and to investigate the design factor and operating conditions. The SSTI(Standard Stoker Type Incinerator) proposed in this study was modified from the type with central flow. It has the characteristics of good mixing between refuse and hot combustion gas in primary combustion chamber and between unburned gas inflowing and secondary air jet in secondary chamber. By predictive results, the SSTI was no recirculation zone in secondary chamber so that mixing time was increased with high residence time. It has good characteristics of combustion and low emission. Parametric screening studies have been understood with phenomenon of combustion in incinerator.