• Title/Summary/Keyword: Energy load calculation

Search Result 240, Processing Time 0.028 seconds

Study on critical buckling load calculation method of piles considering passive and active earth pressure

  • Chen, Yong-Hui;Chen, Long;Xu, Kai;Liu, Lin;Ng, Charles W.W.
    • Structural Engineering and Mechanics
    • /
    • v.48 no.3
    • /
    • pp.367-382
    • /
    • 2013
  • Different types of long slender pile shall buckle with weak soil and liquefied stratum surrounded. Different from considering single side earth pressure, it was suggested that the lateral earth pressure can be divided into two categories while buckling: the earth pressure that prevent and promotes the lateral movement. Active and passive earth pressure calculation model was proposed supposing earth pressure changed linearly with displacement considering overlying load, shaft resistance, earth pressure at both sides of the pile. Critical buckling load calculation method was proposed based on the principle of minimum potential energy quoting the earth pressure calculation model. The calculation result was contrasted with the field test result of small diameter TC pile (Plastic Tube Cast-in-place pile). The fix form could be fixed-hinged in the actual calculation assuring the accuracy and certain safety factor. The contributions of pile fix form depend on the pile length for the same geological conditions. There exists critical friction value in specific geological conditions that the side friction has larger impact on the critical buckling load while it is less than the value and has less impact with larger value. The buckling load was not simply changed linearly with friction. The buckling load decreases with increased limit active displacement and the load tend to be constant with larger active displacement value; the critical buckling load will be the same for different fix form for the small values.

Study on the Effect of Earthquake Loads for Fixed Offshore Wind Turbines According to Soil Type (지반 종류에 따른 고정식 해상 풍력발전기 지진 하중 영향 연구 )

  • Yongoon Oh;Jeonggi Kim;Miseon Kim;Jonghun Jung;Johyug Bang
    • Journal of Wind Energy
    • /
    • v.14 no.1
    • /
    • pp.14-20
    • /
    • 2023
  • In this study, using the commercial software Bladed developed by DNV for integrated load calculation of wind turbines, the generation of seismic waves according to soil type based on Korea's domestic regulations, and load calculation considering earthquake conditions were performed according to the IEC standard, and load in the main coordinate system of the fixed offshore wind turbine was calculated. By comparing the calculated load with the design load of the fixed offshore wind turbine, the effect of earthquake loads according to soil type on the main components of fixed offshore wind turbines was evaluated. As a result of the evaluation, when an earthquake load on a wind turbine is considered, the effect of the earthquake load is related to the natural frequency of the major components and the magnitude of the adjacent acceleration in the earthquake response spectrum, and the earthquake load differs according to soil type and may exceed the design load.

The study of the solar radiation emitted per hour in Incheon applied in load calculation programs (부하계산 프로그램에서 적용되는 인천지역의 시간당 일사량에 관한 연구)

  • Yoo, Ho-Chun;Lee, Seon-Dong
    • Journal of the Korean Solar Energy Society
    • /
    • v.30 no.6
    • /
    • pp.108-117
    • /
    • 2010
  • Although many researches of simulation programs to predict climate under the current climate change have been performed but more detailed studies of weather date which might influence the load of buildings seem insufficient. In this study, in Incheon are analyzed IES (Integrated Environmental Solutions)6.0, Ecotect 2010, EnergyPlus v4.0's IWEC file and ISO-TRY, the Korean standard weather data provided by the Korean Solar Energy Society for direct normal radiation which is used in load calculation programs. The results show that the radiation of the programs is the same as that of direct normal radiation per month but has a mere difference, compared with the radiation per hour and IWEC has also 77.12% when compared with ISO-TRY, meaning that it could affect load values of buildings when applied to them. And in case of ISO-TRY, it could be judged that the application of test reference year applied by the data measured has higher reliability than IWEC file.

Verification and Application of MASTER for Load Follow Operation

  • Park, Yong-Soo;Cho, Byung-Oh;Lee, Chang-Ho;Jung, Yil-Sup;Park, Chan-Oh
    • Proceedings of the Korean Nuclear Society Conference
    • /
    • 1996.05a
    • /
    • pp.231-236
    • /
    • 1996
  • The xenon dynamics module in the nuclear design code MASTER was verified through a simulation calculation. The simulation result shows that the xenon dynamics module in MASTER can trace and predict xenon behavior with accuracy under any core transient state and therefore can simulate load follow operations.

  • PDF

Cost-Effectiveness Evaluation of Energy Conservation Programs Using Avoided Operating Cost Calculation (운전회피비용 계산을 이용한 효율향상 프로그램의 비용효과 분석)

  • 김회철;이기송;박종배;신중린;신점구
    • Journal of Energy Engineering
    • /
    • v.11 no.4
    • /
    • pp.317-323
    • /
    • 2002
  • This paper proposed the calculation method of the generation operating avoided cost to cost-effectiveness evaluation of energy conservation programs that compounded the Proxy Plant Method and Load Decrement Method. This method introduced an operating index of the Energy Efficiency Demand-Side Management (EEDSM) resources based on the end-user's behaviors on the electricity power usage. The operation index is applied to calculate the hourly operating capacity of diffused high-efficiency appliances. And the operating capacity on the peak load hours for reference load is computed through the reduction of the peak load that contributes to that hour. Also, the proposed method evaluated the effect of EEDSM resources. The IEEE-RTS is adopted as a sample system to analyze impacts of an EEDSM. This paper, we have analyzed the effect of EEDSM upon the changes in the generation of generator, generation cost and the system marginal price (SMP). This method can be used to evaluate the impact of the diffused DSM resource and to estimate the impact in short-term EEDSM program. Further, result of the calculation can be utilized to pabulum for effect analysis of EEDSM resources.

Analysis of Heating Energy in a Korean-Style Apartment Building 3 : The Effect of Room Condition Settings (한국형 아파트의 난방에너지 분석 3 :실내설정조건의 영향)

  • Park, Yoo-Won;Yoo, Ho-Seon;Hong, Hi-Ki
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
    • /
    • v.17 no.8
    • /
    • pp.722-728
    • /
    • 2005
  • The present paper deals with heating energy estimation in Korean-style apartments, paying special attention to the effect of room condition settings. Two types of heating modes are considered: continuous single-zone and scheduled multi-zone. In the latter, zones during unoccupied periods remain unconditioned. Also analyzed are sensitivities in heating energy with respect to the air change rate and the set temperature. The energy use is estimated with TRNSYS 15, a dynamic load calculation program. Heating energy for the actual residential condition (1.0 ACH and $24^{\circ}C$) appears to be nearly the same as that for a typical design standard (1.5 ACH and $20^{\circ}C$). The air change rate affects heating energy as sensitive]y as the set temperature. For all the simulated cases, the scheduled multi-zone heating mode is more energy-efficient than the continuous single-zone. Heating energy depends appreciably on the shading factor. It is expected that considerable heating energy for apartment houses can be saved by employing a multi-zone mode along with appropriate control devices.

Evaluation on Reducing Peak Cooling Load Based on Dynamic Load Model of Building Perimeter Zones (건물의 외주부 존에 대한 동적 부하모델 이용 피크냉방부하 저감효과 분석)

  • Lee, Kyoung-Ho;Brau, James E.
    • Journal of the Korean Solar Energy Society
    • /
    • v.31 no.4
    • /
    • pp.1-8
    • /
    • 2011
  • In this paper, inverse building modeling was applied to building perimeter zones which have different window orientation. Two test zones of east-facing and west-facing zones in ERS(Energy Resource Station) building, which is representative of small commercial building, was used to test performance of cooling load calculation and peak cooling load reduction. The dynamic thermal load model for the east and west zone was validated using measured data for the zones and then it was used to investigate the effect of peak cooling load reduction by adjustment of indoor cooling temperature set points during on-peak time period. For the east zone, the peak load can be reduced to about 60% of the peak load for conventional control even without any precooling. For the west zone, PLR is nearly independent of the start of the on-peak period until a start time of 1pm. Furthermore, PLR has a small dependence on the precooling duration. Without any precooling, the peak cooling load can be reduced to about 35% of the peak load associated with conventional control.

A Study on the Optimal Method of Loss Calculation in Distribution System (배전계통에 있어서 최적 손실산정 기법에 관한 연구)

  • 김미영;노대석;황혜미;김광호;신성수;김재언
    • The Transactions of the Korean Institute of Electrical Engineers A
    • /
    • v.53 no.6
    • /
    • pp.340-349
    • /
    • 2004
  • Recently, the needs and concerns for the power loss are increasing according to the energy conservation at the level of the national policies and power utilities's business strategies. Especially, the issue of the power loss is the main factor for the determining the electric pricing rates in the circumstances of the deregulation of electrical industry. However, because of the lacking of management for power loss load factors (LLF), it is difficult to make a calculation for the power loss and to make a decision for the electric rates. And loss factor(k-factor), which is a most important factor for calculation of the distribution power loss, has been used as a fixed value of 0.32 since the fiscal year 1973. Therefore, This study presents the statistical calculation methods of the loss factors classified by load types and seasons by using the practical data of 65 primary feeders which are selected by proper procedures. Based on the above the algorithms and methods, the optimal method of the distribution loss management classified by facilities such as primary feeders, distribution transformers and secondary feeders is presented. The simulation results show the effectiveness and usefulness of the proposed methods.

Optimal Calculation Method of Distribution Loss in Distribution Systems

  • Rho Dae-Seok
    • KIEE International Transactions on Power Engineering
    • /
    • v.5A no.2
    • /
    • pp.109-115
    • /
    • 2005
  • Recently, the needs and concerns regarding power loss have been increasing according to energy conservation at the level of the national policies and the business strategies of power utilities. In particular, the issue of power loss is the main factor for determining rates for electrical consumption in the deregulation of the electrical industry. However, because of the lack of management for power loss load factors (LLF) it is difficult to make a calculation for power loss and to make a decision concerning the electric rates. Furthermore, loss factor (k-factor) in Korea, which is of primary significance in the calculation of distribution power loss, has been used as a fixed value of 0.32 since the fiscal year 1973. Therefore, this study presents the statistical calculation methods of the loss factors classified by load types and seasons by using the practical data of 65 primary feeders that have been selected by appropriate procedures. Based on the above, the algorithms and methods, as well as the optimal method of the distribution loss management classified by facilities such as primary feeders, distribution transformers and secondary feeders is presented. The simulation results demonstrate the effectiveness and usefulness of the proposed methods.

Customer Baseline Load Calculation using Time Series Prediction Technique in Energy Efficiency Programs (시계열 모델을 이용한 행동기반 에너지 효율화 프로그램의 고객기준부하 산정 방안)

  • Koh, Sae-Hyun;Joo, Sung-Kwan;Lee, Jae-Hee;Moon, Guk-Hyun;Wi, Young-Min
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.68 no.1
    • /
    • pp.19-26
    • /
    • 2019
  • As global demand for energy, energy prices, and power generation has increased worldwide, the government is turning to supply-oriented electricity supply and demand policies, such as behavior-based energy efficiency programs. In order to measure the implementation effect of the behavior-based energy efficiency program, the energy reduction must be accurately calculated by calculating the customer baseline load.