成果報告書詳細
管理番号20150000000356
タイトル*平成26年度中間年報 再生可能エネルギー熱利用技術開発 コストダウンを目的とした地中熱利用技術の開発 戸建住宅及び小規模-中規模建築物を対象とした地中熱配管埋設工法の研究開発
公開日2015/6/16
報告書年度2014 - 2014
委託先名旭化成建材株式会社
プロジェクト番号P14017
部署名新エネルギー部
和文要約
英文要約Title : Development of application technology of renewable thermal energy - Technical development of geothermal application aimed at cost reduction / Research and development on installation method of heat retraction tubes applicable to houses and small to mid-size buildings.

The following subjects are set as the targets of this project;(1)Optimization in shape of blade of steel piles: To determine effect in terms of time saving and volume of soil discharge with different shapes of blade as variable. In this fiscal year test sites were reviewed. (2)Development of bottom cap: the bottom cap shall avoid soil or rocks from entering into piles or breakage during operation. Also it should be detachable when drilling pile reaches its bottom point. A cap was studied and manufactured on trial and detachment was tested above ground in the current year. (3)Development of steel pile joint: the development of the joint for small-size piles aims to achieve the following targets; 1) Prevention of ground water or soil from entering into piles. 2) Structure that enables joint connection easier and faster. 3) Strength with sufficient safety coefficient against possible forces during operation. 4) No protrusion on inner surface of piles as U-shape tube is inserted. 5) Less friction against soil during drilling operation. This year we reached the conclusion from technical research results that spline joint is the most suitable that can meet the above-mentioned targets of 1), 2), 4) and 5). Stress was analyzed by three-dimension-FEM and a section design was made to clear the condition 3). Then we made a trial joint with enough strength against torque and tensile strength in related to 3) that were expected during drilling with the small-size piling rig and confirmed the joint had enough safety coefficient. (4)Optimization of layout of heat retraction tubes : to study potentials of application in shallow ground (10-40m depth) to minimize costs of heat exchange system, and also to research optimal layout of the retraction tubes, simulation will be done with analysis of three dimension thermal response. Then analysis will be made with different distances, layout of heat tubes, heat conductivity, and time span of heat retraction and radiation. In the current year inter-influences were analyzed for 3 consecutive months in model ground simplified in terms of depth (28m x 28m x 1m depth) with intense installment of heat retraction tubes. From this analysis we assume the tubes should be installed at more than 4m intervals or at 2m intervals without exceeding 2 in the number of adjacent tubes in order to limit decrease in the performance of the heat exchanger by less than 30%. In consideration of the performance of heat exchanger in related to heat conductivity, the performance did not have much influence on the intervals. From these test results, we concluded overall performance shall be calculated from tube layout if ground heat conductivity can be roughly estimated. (5)Making business plan : ground condition data were collected nationwide during this fiscal year.
ダウンロード成果報告書データベース(ユーザ登録必須)から、ダウンロードしてください。

▲トップに戻る