• Title/Summary/Keyword: Design ice load

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A Measurement of Sea Ice Properties at Chukchi Borderland During the Summer (여름철 Chukchi Borderland 부근 해빙 재료특성 계측)

  • Jeong, Seong-Yeob;Choi, Gul-Gi
    • Journal of the Society of Naval Architects of Korea
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    • v.49 no.1
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    • pp.45-51
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    • 2012
  • Sea ice properties have been considered a key indicator in the structural design criteria of icebreaking vessels and arctic offshore platforms to estimate design ice load and resistance for their safety management in Arctic Ocean. A measurement study of sea ice properties was conducted during July to August of 2011 with the Korean icebreaking research vessel "Araon" around Chukchi Borderland. The sea ice concentration appears to be rapidly decreasing during this cruise. Ice condition seems to be thick second-year ice and multi-year ice and then, a lot of melt ponds were observed in the surface of ice floe. Calculated flexural strength of sea ice was about 250~550kPa, ice thickness was roughly 1.3~3.0m. In this research we performed field experiment to measure ice temperature along the depth, thickness, density, salinity, brine volume ratio and crystal structure. Apparent conductivities derived with the electromagnetic induction instrument were compared to drill hole measurement results and accuracy of sea ice thickness estimation formula was discussed.

Prediction of practically chargeable cold energy in an ice storage system (빙축열시스템의 실질적인 최대 축열 가능량 예측)

  • Lee, D.-Y.;Kang, B.H.;Kim, M.S.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.11 no.1
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    • pp.133-146
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    • 1999
  • The charge operation of an ice storage system has been analyzed in this paper. The thermal characteristics of major components of the ice storage system. i.e., the refrigerator and the ice storage tank are evaluated from performance tests on an existing ice storage system. Based on the measured data for thermal characteristics, a simulation is carried out for the charge operation and the effect of the refrigerator size on the system performance is investigated. The results indicate that the larger the refrigerator size for a given storage capacity, the lower the inlet temperature of the ice storage tank so that the lower the efficiency of charge operation. It is also found that there exists an optimal size of the refrigerator with which the ice storage at the end of the charge operation is maximized, but the complete charge is not possible even with the optimally sized refrigerator. This leads to the result that the design capacity of the storage tank should be larger than the required amount of cold energy for the daytime cooling considering the practically chargeable amount of cold energy during the nighttime. Where the cooling load sharing of the storage is 40%, the nominal capacity of an ice storage tank needs to be larger than the required storage amount by 30%.

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Analysis Method of Ice Load and Ship Structural Response due to Collision of Ice Bergy Bit and Level Ice (유빙 및 평탄빙의 충돌에 의한 빙하중과 선체구조응답 해석기법)

  • Nho, In Sik;Lee, Jae-Man;Oh, Young-Taek;Kim, Sung-Chan
    • Journal of the Society of Naval Architects of Korea
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    • v.53 no.2
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    • pp.85-91
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    • 2016
  • The most important factor in the structural design of ships and offshore structures operating in arctic region is ice load, which results from ice-structure interaction during the ice collision process. The mechanical properties of ice related to strength and failure, however, show very complicated aspect varying with temperature, volume fraction of brine, grain size, strain rate and etc. So it is nearly impossible to establish a perfect material model of ice satisfying all the mechanical characteristics completely. Therefore, in general, ice collision analysis was carried out by relatively simple material models considering only specific aspects of mechanical characteristics of ice and it would be the most significant cause of inevitable errors in the analysis. Especially, it is well-known that the most distinctive mechanical property of ice is high dependency on strain rate. Ice shows brittle attribute in higher strain rate while it becomes ductile in lower strain rate range. In this study, the simulation method of ice collision to ship hull using the nonlinear dynamic FE analysis was dealt with. To consider the strain rate effects of ice during ice-structural interaction, strain rate dependent constitutive model in which yield stress and hardening behaviors vary with strain rate was adopted. To reduce the huge amount of computing time, the modeling range of ice and ship structure were restricted to the confined region of interest. Under the various scenario of ice-ship hull collision, the structural behavior of hull panels and failure modes of ice were examined by nonlinear FE analysis technique.

Material Properties of Arctic Sea Ice during 2010 Arctic Voyage of Icebreaking Research Vessel ARAON: Part 1 - Sea Ice Thickness, Temperature, Salinity, and Density - (쇄빙연구선 ARAON호를 이용한 북극해 해빙의 재료특성 (1) - 해빙의 두께, 온도, 염도, 밀도 계측 -)

  • Park, Young-Jin;Kim, Dae-Hwan;Choi, Kyung-Sik
    • Journal of Ocean Engineering and Technology
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    • v.25 no.2
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    • pp.55-61
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    • 2011
  • A field trial in an ice-covered sea is one of the most important tasks in the design of icebreaking ships and offshore structures. To correctly estimate the ice load and ice resistance of a ship's hull, it is essential to understand the material properties of sea ice during ice field trials and to use the proper experimental procedure for gathering effective ice data. The first Korean-made icebreaking research vessel, "ARAON," had her second sea ice trial in the Arctic Ocean during the summer season of 2010. This paper describes the test procedures used to obtain proper sea ice data, which provides the basic information for the ship's performance in an ice-covered sea and is used to estimate the correct ice load and ice resistance of the IBRV ARAON. The data gathered from the sea ice in the Chukchi Sea and Beaufort Sea during the Arctic voyage of the ARAON includes the temperature, density, and salinity of the sea ice, which was believed to be from two-year old ice floes. This paper analyses the gathered sea ice data in comparison with data from the first voyage of the ARAON during her Antarctic Sea ice trial.

A Study on Analysis of Air Conditioning System in Ice Rinks (빙상경기장의 공조시스템 분석에 관한 연구)

  • Chae, Mun-Byoung;Yun, Hae-Dong;Lee, Jong-Sin;Byun, Woon-Seob
    • Proceedings of the SAREK Conference
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    • 2009.06a
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    • pp.441-446
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    • 2009
  • A modern industrial society is presently considering not only cultural life but also health promotion to enhance the quality of life. There are many ways to enjoy the wellbeing life. Especially, ice-skating has been focused on as leisure sports with many remarkable advantages. Even though ice-skating was recognized as winter sport, nowadays people enjoyed skating are increased more and more because of indoor ice link. So, construction of indoor ice link has been boomed up. However, The techniques of ice link freezing system are insufficient because the ice link freezing system on the local construction was designed by advanced country techniques. So, this study has been conducted to analyze the air conditioning and refrigeration system in existing local ice link to suggest the design method of ice link.

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Analysis of Thermal and Flow Characteristic in Ice Storage Tank (빙축열조 내부의 열적유동 특성 해석)

  • Kim, Y.I.;Hong, H.K.;Bai, C.H.;Kim, Y.I.;Yoon, H.S.
    • The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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    • v.17 no.4
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    • pp.369-376
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    • 1988
  • Among several methods to solve the unbalanced electric power load, the Ice Storage System (ISS) for the air conditioning is relatively easy to realize and gives big effect on balancing the electric power load. The goals of this study are to develop the practical ISS for the air conditioning through the design, manufacturing and performance test of the experimental ISS (size $0.335m^3$, cold storage capacity 14200 kcal, IPF 0.4). Thermal fluid motion inside the ice storage tank during cooling storage and cooling release are studied. The data are analyzed by the dispersion analysis and optimal design conditions are derived from the result.

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A Study on the Development of the Large Building Air-conditioning System with the Regenerative Ice-energy and its Computer Aided Design (빙축열을 이용한 대형빌딩 공기조화시스템 개발과 설계전산화에 관한 연구)

  • 권형정;김원영;김용모;김경근
    • Journal of Advanced Marine Engineering and Technology
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    • v.15 no.5
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    • pp.38-46
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    • 1991
  • In the design of an electric power plant, the capacity to meet the peak load demand is one of the important factors to be considered. This peak load usually occurs when the most of the cooling air-conditioning systems are being operated during daytime in summer season. Therefore, it is necessary to construct an additional electric power plant and to develop the new air-conditioning system for relieving the peak load. This paper analysed the performance characteristics of this experimental regenerative ice energy system by means of a bundle of the heat-pipes. And the result of this analysis was applied to the simulation of an air-conditioning system model. Also, an operation program of moisture air was made according to air load and in order to computerize the air-conditioning system a CAD program was developed by the properties of moisture air.

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A Study on Estimation of Cooling Load for Effective Control of Ice Thermal Storage System (빙축열 시스템의 효율적인 제어를 위한 냉방부하 예측에 관한 연구)

  • Yoo, Seong-Yeon;Han, Kyu-Hyun;Lee, Je-Myo;Han, Seung-Ho
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.20 no.2
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    • pp.128-136
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    • 2008
  • It is necessary to estimate the cooling load of the next day for effective control of ice thermal storage system. In this paper, new methodology is proposed to estimate the cooling load using design parameters of building and predicted weather data. Only six input parameters such as sensible heat coefficient and constant, latent heat coefficient and constant, maximum and minimum temperature are necessary to obtain hourly distribution of cooling load for the next day. Two benchmarking buildings(hospital and research institute) are selected to validate the performance of the proposed method, and the estimated cooling loads in hourly and daily bases are calculated and compared with the measured data for E hospital. The estimated results show fairly good agreement with the measured data for both buildings.

A Comparative Analysis of Sea Ice Material Properties in the Amundsen Sea, Antarctica (남극 아문젠해에서 계측된 해빙의 재료특성 비교 분석)

  • Choi, Kyungsik;Kim, Hyun Soo;Ha, Jung Seok;Lee, Chun-Ju
    • Journal of the Society of Naval Architects of Korea
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    • v.51 no.3
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    • pp.254-258
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    • 2014
  • Field trial in ice-covered sea is one of the most important tasks in the design of icebreaking ships. To correctly estimate ice load and ice resistance on ship's hull, It is essential to understand the material properties of sea ice during ice field trials and to perform the proper experimental procedure by gathering sea ice data. A measurement of sea ice properties was conducted during February and March of 2012 with the Korean Icebreaking research vessel "ARAON" in the Amundsen Sea, Antarctica. This paper describes a test procedure to obtain sea ice data which provide basic information to estimate ice loads and icebreaking performance of the ship. The data gathered from sea ice field trials during the 2012 Antarctic voyage of the ARAON includes ice temperature/salinity/density and the compressive/flexural strength of sea ice. This paper analyses the gathered Antarctic sea ice material properties comparing with the previous data obtained during ARAON's Arctic and Antarctic voyages in 2010.

A Study on the Estimation of Temperature, Humidity and Cooling Load (온도, 습도 및 냉방부하 예측에 관한 연구)

  • Yoo, Seong-Yeon;Han, Seung-Ho;Lee, Je-Myo;Han, Kyou-Hyun;Noh, Kwan-Jong
    • Proceedings of the SAREK Conference
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    • 2006.06a
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    • pp.80-85
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    • 2006
  • The peak demand of electricity in summer season mainly comes from the day time cooling loads. Ice thermal Storage System (ITSS) uses off-peak electricity at night time to make ice for the day time cooling. In order to maximize the use of cold storage in ITSS, the estimation of day time cooling load for the building is necessary. In this study, we present a method of cooling load estimation using 5 years of normalized outdoor temperature, relative humidity, and the building construction data. We applied the hourly-based estimation to a general hospital building with relatively less sudden heat exchange and the results are compared with the measured cooling load of the building. The results show that the cooling loads estimation depends on the indoor cooling design temperature of the building.

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