• 한국태양에너지학회 논문집
• /
• 제27권3호
• /
• pp.107-115
• /
• 2007

The measured solar radiation incident on tilted surfaces has been widely used as important solar radiation data in installing photovoltaic arrays. To optimize the incident solar radiation, the slope, that is the angle between the plane surface in question and the horizontal, and the solar azimuth angles are needed for these solar photovoltaic systems. This is because the performance of the solar photovoltaic systems is much affected by angle and direction of incident rays. The expert system can predict the optimum installation angle of photovoltaic arrays with those factors.

• 한국지반공학회지:지반
• /
• 제13권4호
• /
• pp.55-66
• /
• 1997

본 연구에서는 그물식 뿌리말뚝의 타설경사각과 횡방향저항력 사이의 관계를 비교분석하고자 여러가지의 타설경사각을 갖는 모형 그물식 뿌리말뚝을 제작하여 모형지반에 설치한 다음 횡방 향재하시험을 하였다. 모형 뿌리말뚝의 배치는 12개의 말뚝을 6개씩 2개의 크고 작은 동심원에 접하도록 하였는데 각각의 시험에 사용한 모형말뚝은 $0^{\circ}\;, 5^{\circ}\;, 10^{\circ}\;, 15^{\circ}\;, 20^{\circ}\;, 25^{\circ}$의 타설경사각을 갖 는 직경 5m의 강봉에 모래를 입힌 것이다. 횡방향하중을 받는 뿌리말뚝에 있어서 실험을 통해 얻은 하중변위곡선으로 판단해 볼 때 1mm정도의 횡방향변위에서는 타설경사각이 커질수록 횡방향저항력도 커지지만 최적 타설경사 각은 횡방향변위가 증가할수록 감소하며 6mm의 횡방향변위에서는 $17.5^{\circ}$. 타설경 사각 $0^{\circ}$횡방향저항력에 대한 최적 타설경사각에서의 횡방향저항력의 비는 횡방향변위가 증가할수록 감소하므로 횡방향변위가 커질수록 말뚝을 경사지게 배치함으로써 얻는 저항력 증대효과는 줄어들 것으로 예상된다.

• 한국지열·수열에너지학회논문집
• /
• 제14권4호
• /
• pp.61-67
• /
• 2018

Solar energy depends on the altitude and azimuth of the sun, and the amount of energy collected on the slope depends on the latitude of the area being installed. However, since most solar heating systems are fixed to the ground, it is necessary to analyze the optimal installation angle from the early design stage. However, problems arise when energy consumption is not considered together because heating systems are not used in the summer In this study, the optimum installation angles of the solar collectors according to the latitude of the installation area are not simply determined by the amount of energy collected, but because the system is overheated due to climate change or energy usage patterns, And the amount of additional energy input.

• 설비공학논문집
• /
• 제22권9호
• /
• pp.635-640
• /
• 2010

This study is suggested tilt window type to be restrained solar radiation through vertical window type in buildings. The shading and aesthetical effect of buildings would be solved by installation of tilt window type. For investigate optimum an angle of tilt window and building azimuth in reference region, the distance of transmitted solar radiation is calculated. The results of calculation showed optimum an angle of tilt window is obtained $7^{\circ}$ that the distance of transmitted solar radiation is 20% of 1.5m of balcony width. In case of an tilt window angle of $7^{\circ}$, the optimum building azimuth is showed $SW15^{\circ}{\sim}SE15$.

• 태양에너지
• /
• 제6권1호
• /
• pp.47-59
• /
• 1986

This paper presents the establishment of optimum design conditions and economic evaluation for solar hot water system. The aim of this study is to present thermal performance of solar heating systems and to determine their performance as a function of collector size, storage capacity, tilting of collector and other factors. By analyzing its performance under the various conditions, optimum design of solar heating system can be obtained. System performance are obtained monthly and yearly basis respectively. At the same time the economics of various systems are evaluated. For the computer simulation Mokpo, Kangnung, Chupungnyong and Seoul are selected for particular installation places. As a result, the optimal design condition of solar heating system considering the following factors such as installation angle of collector, capacity of storage tank, collector size in each place can be obtained as follows; (1) Installation angle of collector Tilt = lattitude (2) Capacity of storage tank Solar domestic hot water system : $45\;1/m^2$ Multifamily solar domestic hot water system : $35\;1/m^2$ (3) Collector size i) Solar domestic hot water system Seoul & Chupyungyong area : $11.52\;m^2$ Mokpo area : $8.64\;m^2$ ii) Multifamily solar domestic hot water system Seoul, Chupyungyong & Mokpo area : $345.6\;m^2$ Kangnung area : $259.2\;m^2$

• 한국태양에너지학회 논문집
• /
• 제29권2호
• /
• pp.47-54
• /
• 2009

The amount of incident rays over inclination according to direction has been widely utilized as important data m installing solar thermal systems. To optimize the incident solar radiation, the slope, that is the angle between the plane surface in question and the horizontal, and the solar azimuth angles are needed for these solar thermal systems. This is because the performance of the solar thermal systems in much affected by angle and direction of incident rays. Recognizing that factors mentioned above are of importance, actual experiment on the moving route of the sun have been performed in this research to obtain the angle of inclination with which the maximum incident rays can be absorbed. After all, the standard for designing highly optimized solar thermal systems will be provided for designers and employees working in the solar collector related industries.

• 한국추진공학회지
• /
• 제2권1호
• /
• pp.88-94
• /
• 1998

이 연구에서는 100인승 항공기 급의 저익-주익장착나셀(wing mounted nacelle)의 추진기관 장착설계 방법을 제시하였다. 장착설계 방법을 구체적으로 설명하기 위해 세부적인 설계제한조건(design constraint)과 설계요구조건(design requirement and objectives)을 정의하고, 그러한 기준을 근거로 실례의 항공기(K100)를 사용하여 주익장착방식의 장착설계를 수행하였다. 장착설계는 간섭항력(interference drag), roll clearance, ground clearance, nose gear collapse margin, rotor burst, 연료탱크용량 등의 설계제한사항들을 고려하여 엔진성능을 만족시킬 수 있는 최적의 나셀 장착위치(spanwise, FS, WL)와 장착각도(toe-in, incidence, droop angle), wing dry bay의 위치와 크기를 결정하여 향후에 개발될 주익장착방식의 추진기관 장착설계에 활용될 수 있는 설계절차를 구축하였다.

• 한국분무공학회지
• /
• 제16권4호
• /
• pp.201-209
• /
• 2011

Optimum engine performance is obtained when the spray characteristics is well matched to the geometry of a combustion chamber. Among many parameters governing the combustion performance in internal combustion engine, fuel supply characteristics and atomization are important performance factors. Therefore, spray characteristics of high pressure multi-hole injector has been studied experimentally. An experimental test system has been made to operate high pressure injection system and to visualize spray behavior. Spray visualization has been performed to analyze spray formation, spray cone angle, bent angle and penetration length. Spray interaction with piston has been analyzed with various injector installation angle, injection pressure and ambient pressure. Test results show that penetration length is greatly influenced by the injection pressure. Penetration length is decreased as ambient pressure increased. Spray cone angle is increased as injection pressure and ambient pressure increased. However, bent angle is not influenced by the change of injection pressure and ambient pressure. Spray cone angle distribution map is plotted using the experimental data. Fuel movement around the spark-plug has been enforced as increasing injector installation angle.

• KIEAE Journal
• /
• 제15권4호
• /
• pp.5-11
• /
• 2015

Purpose: Recently, renewable energy system has been widely used to reduce the energy consumption and CO2 emission of building. A photovoltaic/thermal(PVT) system is a kind of efficient energy uses, which is combined with photovoltaic module and solar thermal collector. PVT system removes heat from PV module by through thermal fluid to raise the performance efficiency of the PV system. However, though PVT system has the merit of the improved efficiency in theoretical approach, there have been few performance analysis for PVT system using the dynamic energy simulation. In this study, in order to establish the optimum design method of this system, simulation was conducted by using individual system modules. Method: For the dynamic simulation, TRNSYS17 was used and local weather data was utilized. Furthermore, the system performance in various installation condition was calculated by case studies. Result: As a result, the amount of electric generation and heat production in each case was found by the simulation. The gap of system performance was also evident according to the installation condition.

• KIEAE Journal
• /
• 제12권1호
• /
• pp.113-118
• /
• 2012

The photovoltaic is one of the most important sustainable technologies appliable to architectures. The power performance mainly depends on the installation conditions of them. This study aims to evaluate the power performance of photovoltaic system by the installation conditions, the tracking methods and reflecting mirrors. For the study, the Solar Pro computer simulations have been conducted on installation angles, solar azimuth and solar altitude. Also, the field mock-up tests are performed to of its application to verify the simulation results. Both the results of the experiment and the simulation have proved that the efficiency of 90-degree fixed angle method was higher than that of 30-degree fixed angle, the efficiency of altitude tracking was better than that of azimuth tracking method, and changing both the altitude and the azimuth together is more efficient rather than the shortened tracing way. In addition, the light-concentrating method in which the incidence angle of the sun is controlled by an adhered reflector has been analyzed to have better efficiency than the general method of tracing according to the orbit of the sun. Therefore, this thesis is expected to offer the basic data to set a more effective tracing-type of photovoltaic power generation system in the future. For this, more researches are to be conducted hereafter on a high efficiency drive motor and the establishment of an economic system.