• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.2984-2988
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• 2008

Numerical analyses are carried out in order to understand complex thermal characteristics of a gas turbine combustor liner such as combustion gas temperatures, wall temperatures and heat transfer distributions. As results, The maximum internal and external heat transfer is $2218W/m^2K$ and $2358W/m^2K$, respectively. The combustion gas temperatures range is 673K to 1760K. A range of temperature on TBC is 676K to 1382K. Lastly, temperature range on outer surface of combustion liner cooled by compressed air is 676K to 1188K.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2011년도 제37회 추계학술대회논문집
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• pp.988-991
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• 2011

본 연구는 공기흡입식 추진기관을 위한 슬롯형 냉각라이너의 설계변수가 냉각성능에 미치는 영향을 살펴보기 위한 것이다. 슬롯형 냉각라이너의 설계변수 세가지를 선정하여 냉각성능에 미치는 영향을 분석하였다. 본 논문에서는 슬롯형 냉각라이너의 각 설계변수에 대한 열전달 계산으로부터 얻어진 내벽온도 계산결과를 비교하였다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2010년도 제35회 추계학술대회논문집
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• pp.642-647
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• 2010

막냉각은 고온의 연소가스에 장시간 노출되어 있는 공기흡입식 추진기관의 연소실 내벽을 열적으로 보호하기 위해 사용하고 있으며, 슬롯형 냉각라이너를 이용한 막냉각 방법은 냉각특성을 향상시키기 위해 오랫동안 연구되어 왔다. 본 논문에서는 다중 슬롯형 냉각라이너의 연소영역과 냉각영역에서의 기체역학적 유동 및 열전달 계산에 대한 연구결과를 기술하였다.

• Journal of Advanced Marine Engineering and Technology
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• 제20권4호
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• pp.36-42
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• 1996

Analysis of heat transfer on small-size Diesel engine is required for the development of high performance and efficiency engine. This basic study aims to establish heat transfer technique for marine Diesel engine. The main results from this study are as follows : 1) Overall engine heat transfer correlation of Re-Nu. 2) Radiant heat flux as fraction of total heat flux over the load range of several different Diesel engine. 3) Characteristics of heating curves on piston, cylinder liner and head. 4) Surface heat flux versus injection timing.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2003년도 제20회 춘계학술대회 논문집
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• pp.127-130
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• 2003

This paper presents the numerical thermal analysis for regeneratively cooled rocket thrust chambers. An integrated numerical model incorporates computational fluid dynamics for the hot-gas thermal environment, and thermal analysis for the liner and coolant channels. The flow and temperature fields in rocket thrust chambers is assumed to be axisymmetric steady state which is presumed to the combustion liner. The heat flux computed from nozzle flow is used to predict the temperature distribution of the combustion liner. As a result, we present the wall temperature of combustion liner and the temperature change of coolant.

• 설비공학논문집
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• 제24권3호
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• pp.224-229
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• 2012

The importance of ventilation system is being emphasized by interest of indoor air quality. Especially, heat recovery ventilation system has attracted attention as most effective ventilation plan. Because it can reduce hazardous construction materials, indoor air pollutions, and also can reduce air conditioning energy cost. In heat recovery ventilator, the element core is the most important part. The element core is composed of liner and spacer. And liner and spacer are stacked alternately. On the Liner, heat and humidity transfer are made between supply and exhaust air. And spacer plays a role as a tunnel of exhaust and supply. In this study, we investigated and analyzed the efficiency of a heat recovery ventilator, when the spacer's properties are changed. As a result, difference spacer's properties affect an efficiency of heat recovery ventilator.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2010년 춘계학술대회논문집
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• pp.247-251
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• 2010

It is very difficult to understand and estimate the heat transfer and flow characteristics in the combustor, which is one of main components in the Auxiliary Power Unit (APU), because its flow filed has very complex structure. In this paper, specified is characteristics of injection and flow through different air goles in the liner, which consist of large circular holes film cooling holes, and tangential air swirl holes. The durability of the liner depends on whether the surface of the liner is exposed to the hot gas over 1000 $^{\circ}C$ of a temperature or net. It is proved that the locations of hot spots estimated from the calculation using CFD are matched well with that from the test. In this study, CFD simulations were performed to examine the heat transfer and temperature distributions in and about a liner wall with film cooling on the wall. This computational study is based on the ensemble average continuity, compressible Navier-Stokes, energy, and PDF combustion equations closed by the standard $k-{\varepsilon}$ turbulence model with standard wall functions for the gas phase and the Fourier equations for conduction in the solid phase.

• 오토저널
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• 제2권1호
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• pp.39-50
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• 1980

This paper presents the variations obtained in heat flow rate and engine performance of a four-stroke cycle Diesel engine when there were changes in the temperature of cooling water, compression ratio, injection timing of fuel, and other factors. Heat dissipation of engine cylinder was calculated by the heat transfer coefficient of Nusselt's empirical equation and the analysis of distribution of temperature in cylinder barrel was obtained by the finite element method of two-dimensional steady state heat conduction. In this experiment, the out side temperature of cylinder liner was measured by the data logger, and the temperature distribution of liner was computed by the analysis of triangular finite element model under the assumption due to surface heat flux of cylinder inner surface. The results obtained by this study are as follows. Under the given operating condition, the temperature distribution of cylinder liner by using finite element method shows that the mean temperature of barrel is in accordance with the experimental results of Eichelberg and temperature difference is lower than 4.23.deg. C. The heat dissipation of engine decrease in accordance with the decrease of piston mean velocity, compression ratio, and the increase of coolant temperature. Influence on the delay of injection timing of fuel brings about the decrease of heat rejection over the cylinder at constant test conditions.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2013년도 제46회 KOSCO SYMPOSIUM 초록집
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• pp.123-126
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• 2013

Combustor development requires high fidelity simulation capable of predicting recirculation zone (RZ), temperature field, and pollutant emission. Swirling flow is widely used in combustor for its benefits in efficient mixing and flame stabilization by RZ. Large eddy simulation (LES) is used to calculate swirling flow in an expanding pipe [1], and shows higher accuracy than RANS. Reactive flow modeling using LES and flamelet model is validated with experiments by Barlow et al. [4] and Masri et al. [3]. Finally, heat transfer simulation of Samsung Techwin's combustor liner is presented.

• Journal of Ship and Ocean Technology
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• 제8권4호
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• pp.34-44
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• 2004

Engine visualization is the most important process to develop the new engine. But this step has a major difficulty that is almost impossible to access the engine on running. Therefore, little indication from the experimental and analytical results has been so far. This work has conducted the important issue of developing a quartz liner. And it has given us good qualitative and quantitative results of temperature and stress fields in the quartz cylinder by considering forced convection of outside quartz liner, thickness of the quartz liner and preheating effect to operate quartz engine safely.