• 한국연소학회:학술대회논문집
• /
• 한국연소학회 2004년도 제29회 KOSCI SYMPOSIUM 논문집
• /
• pp.181-186
• /
• 2004

Catalytic combustion is one of the suitable methods which is applicable to micro heat source due to high energy density and no flame quenching. And hydrogen can be oxidized at room temperature with platinum catalyst. So hydrogen-fueled micro catalytic combustor with platinum catalyst can be good and easy-handling heat source for another micro devices. In this work we focused on general catalytic combustion characteristics of hydrogen-air premixed gas in 10mm scale catalytic combustor for the further application to micro scale. Platinum was coated on dense ceramic monolith which can be installed in simple-structured catalytic combustor. We investigated the effect of flow rate, heat loss and platinum percentage in catalyst-coated monolith on catalytic combustion performance by temperature distribution in the combustor. By those results we confirmed catalytic reactivity and estimated reaction area. And we simulated micro scale catalytic reaction by sliced monolith. The results of this work will be important design factors for micro scale catalytic combustor.

• 대한기계학회논문집B
• /
• 제22권11호
• /
• pp.1538-1546
• /
• 1998

The aim of this study is to investigate the characteristics of the catalytic burner to bum LPG and toluene alternately which can be applied to the dryer of an acryl coating process of textile. It was difficult to obtain complete conversion when the catalytic burner was installed to downward direction. The catalytic burner was improved by introducing the forced diffusion combustion air and the premixing air. The optimal operating conditions for the newly improved catalytic burner were obtained. The catalytic burner for toluene mixture was also investigated to incinerate toluene mixture exhausted from drying process. Results showed that the catalytic burner could oxidize toluene mixture completely at the proper operating conditions. Finally, the catalytic burner to bum LPG and toluene alternately was applied to the dryer of acryl coating. By using the catalytic burner, benefits of energy savings and environmental protection were obtained.

• 한국대기환경학회지
• /
• 제15권3호
• /
• pp.249-255
• /
• 1999

We sdudied effect of additives on catalytic activity in thermal catalytic de-NOx process which was composed of thermal reduction, catalytic reduction and catalytic oxidation stage. Pd-Pt/${\gamma}$-$Al_2O_3$ catalysts with the addition of transition metals(Co, Cu, Fe, Ni, W, Zn, Zr) and rare earth metals(Ce, Sr) were prepared by the conventional washcoating method. Those catalysts were characterized by CO pulse chemisorption, ICP, $N_2$ adsorption, SEM and XRD. The effect of catalyst additives on NOx removal for diesel emission was studied in thermal catalytic de-NOx process at reduction temperature(350~50$0^{\circ}C$), space velocity(5,000~20,000 $hr^{-1}$) and the engine load(0~120kW). The concentraton of CO, $CO_2$, NO and $NO_2$ in the exhaust gas increased with the engine load. On the other hand the concentration of $O_2$ decreased. The de-NOx activityof all prepared catalysts increased with respect to high CO and low $O_2$ level in the thermal reduction stage of the process. Insertion of Ce to Pt-Pd/${\gamma}$-$Al_2O_3$ catalyst showed the best activity of all the catalysts under these experimental conditions. De-NOx catalysts are effective to remove CO in addition to NOx in the catalytic reduction stage.

• 한국자동차공학회논문집
• /
• 제10권1호
• /
• pp.45-50
• /
• 2002

Use of a phenomenological model, developed far prediction of catalytic deactivation, is demonstrated in comparing harshness of different driving cycles that are currently used to rapidly age catalytic converters on engine test benches. The model shows that seemingly equivalent driving cycles cause the catalytic converters to reach significantly different levels of deactivation. The comparison of the model prediction with the limited vehicle data seems encouraging despite the simplicity of the model at the current stage of its infancy.

• 한국연소학회:학술대회논문집
• /
• 대한연소학회 2003년도 제27회 KOSCO SYMPOSIUM 논문집
• /
• pp.299-308
• /
• 2003

This paper provides a review of the status and of the perspectives of advanced catalytic combustion for ultra clean combustion of gas turbines and for industrial combustors. The development of catalytic materials and their combustion techniques for gas turbines are briefly reported. The fuel-rich approaches to catalytic combustion are mentioned for a new technology of thermal- and fuel-NOx control. The fuel-rich catalytic combustion are also applicable to the combustor of ceramic gas turbine, and to the combustion of biomess and municipal waste sludge. Some extended technologies of combustion synthesis are introduced for the synthesis of carbon nanotube and of Perovskite combustion catalysts

• 한국연소학회:학술대회논문집
• /
• 한국연소학회 2002년도 제24회 KOSCO SYMPOSIUM 논문집
• /
• pp.79-84
• /
• 2002

The catalytic heat exchanger was designed which employs the regenerative preheating system of combustion air. The characteristics of the catalytic heat exchanger have been experimentally studied at the various operating parameters. The results showed that the mixture velocity did not affect significantly the performance of catalytic combustor whereas the preheating temperature of combustion air affected significantly the conversion rate. The complete conversion was achieved in the catalyzed honeycomb at a preheating temperature of $370-390^{\circ}C$, a mixture velocity of 0.53 $^{\sim}$ 0.75 m/s and an equivalence ratio of 0.19 $^{\sim}$ 0.27. The heat exchange efficiency of the catalytic heat exchanger appeared to be about 75 % when the air of room temperature was used as a working fluid. The results showed that both the heat balance of the system and the mixture conditions determine its stable catalytic combustion.

• 한국연소학회:학술대회논문집
• /
• 한국연소학회 2000년도 제20회 KOSCO SYMPOSIUM 논문집
• /
• pp.169-177
• /
• 2000

The catalytic heat exchanger, which integrates two functions of heat generation and heat exchange into one equipment, was designed and its characteristics were investigated by the experiment and numerical simulation. The surface of the fin tube was deposited with Pd catalyst. The conversion of the mixture in the catalytic heat exchanger was more significantly affected by the inlet velocity of the mixture than by the inlet temperature and equivalence ratio of the mixture. It was found that the catalytic surface area of the fin tubes should be sufficiently increased to make the combustion intensity of the catalytic heat exchanger as high as possible. Results showed that the fin tubes, placed in the triangularly staggered form, should be adjusted so that the mixture flows uniformly over all the catalytic fin surfaces. Numerical simulation results demonstrated that the flow pattern of the mixture significantly affected the conversion of the mixture.

• 대한기계학회논문집B
• /
• 제31권4호
• /
• pp.376-383
• /
• 2007

This research represents the catalytic converter for application in the motorcycle. We have to consider about catalytic converter for reducing exhaust gas strength regarding the displacement volume enlargement. The catalytic converter has been widely used to satisfy the regulations of pollutant emissions from automobiles. Recently, all catalytic converter researches are about automobile. Study about motorcycle catalytic converter has not been conducted yet. In this study, flow uniformity and pressure distribution were simulated in the monolithic inlet of catalytic converter for motorcycle. Exhaust pulsation pressure was set as transient condition about. It was found that flow uniformity shown in base model (0.85) was lower than megaphone model (0.98).

• 산업기술연구
• /
• 제43권1호
• /
• pp.33-41
• /
• 2023

This paper provides a general overview of surface catalytic recombination in hypersonic flow. The surface catalytic recombination phenomena is elaborated in terms of its general overview and numerical modeling associated with it. The general overview of the surface catalytic recombination phenomena describes the elementary surface reactions for the surface catalytic and the role of the surface catalytic recombination efficiency in the heat transfer determination. In the numerical modeling, the surface catalytic recombination is described based on the stagnation-point boundary layer analysis, and finite-rate surface reaction modeling. Throughout this overview manuscript, a general understanding of this phenomena is obtained and can be used as foundation for deeper application with the numerical computational fluid dynamics (CFD) flow solver to estimate the surface heat transfer in the hypersonic vehicles.

• 에너지공학
• /
• 제17권2호
• /
• pp.100-106
• /
• 2008

매트형태의 연소촉매를 사용하는 촉매연소 버너는 발생 열을 원적외선 형태로 피 가열체에 공급할 수 있기 때문에 저온 공정에서 효율적으로 열을 사용할 수 있다. 매트형태 촉매연소 버너의 활용 가능성을 높이기 위해 촉매연소버너를 제작하고 구조에 따른 연소성능에 대해 고찰하였다. 확산식 촉매연소에서는 연소면의 방향이 연소반응에 많은 영향을 주며, 촉매 주위 온도변화에 따른 산소의 확산속도 차이가 촉매 연소 반응 속도에 많은 영향을 주는 것을 알았다. 예혼합 촉매연소에서 연소공기는 이론공기량 보다 조금 많게 공급하는 것이 최적이고, 연소열의 70% 이상이 복사로 전달됨을 알았다.