This invastigation was carried out to estimate the heat transfer coefficient, h_P, in packed bed of grain.
In this analysis, Babcock's approximate solution was adopted to calculate the vale of h_P.
The following conculsion are drawn from the results of this investigation.
1. The effect of air velocity on the value of h_P was arrenged as the relation between Nu and Re, and the following equations were obtained;
glass beads: Nu=0.155Pe^0.92 (25≤Re≤170)
rough rice: Nu=0.0198Re^1.02 (20≤Re≤95)
barley: Nu=0.477x10^-3Re^1.99 (34≤Re≤94)
2. The predicted values of temperature at the each bed length from the approximate solution good agree with the measured values.
3. The values of h_P in packed bed were lowes than those of single kernel and in packed bed, temperature distribution in particle is negligible over the range of this investigation because the values of Biot No. were smaller than 0.1,
4. Air temperature and bed length effect on the value of h_P. In this investgation, however, those effects cannot be analyzed quantitatively. The new model, contains heat loss through the apparatus wall, fluid dispersion and overall heat transfer of particle, should be used to analyze those effects.

抄録全体を表示

The country elevators in Omi-Hachiman city, Shiga Prefecture were analysed by simulation in order to increase the ability of the drying section.
1. Although the receiving pattern varies with the extension of combine harvesting and the understanding of farmers etc., recently this pattern is stable. Therefore this pattern can be used as input data in simulation of the ability of drying section.
2. In the country elevator of 3000t capacity, the amount of treated paddy in the drying section will rise up to 4500t by applying the method of half-drying storage (paddy is dried to 18% W. B., and temporarily stored as long as allowable in quality).
3. With the increment of amount of received paddy, the average amount of temporary storage increases rapidly, while its maximum amount increases with a curve like S letter
4. The working ratio of drying section is almost proportional to the amount of received paddy, but it varies with the total drying amount (defined in Chapter II).
5. The using state of tanks for temporary storage is one of indexes in selecting the proper received amount of paddy.

抄録全体を表示

The application of wellwater spray between double roofs of greenhouse is now being used very effectively in the northern part of Kantoh district to disuse the warm air combustion units in winter.
The authors have been measuring the heating characteristics of this system for two years.
1) The indoor air temperature at night is retained 14.2°C above ambient on an average in the coldest period.
2) The vertical temperature distribution at night is sufficiently uniform and the rate of temperature decrease is limited to about one quarter.
3) Total heat loss in the night is composed of the heat flow from soil floor of one third and the sensible heat supply from spray water of two third.
4) The additional cost of the double roofs with spray equipment is more than compensated for by the advantages of fuel and electricity savings in about seven years.

抄録全体を表示

ミルキングパーラーにおいて, ミルカーの諸仕様変更前後における真空系内圧力変動, 搾乳速度, 搾乳作業能率および乳房に与える影響を比較検討した。主な変更内容は, (1) 設定真空度を380から350mmHgに下げ, (2) 拍動は左右交互方式から前後偏率方式とし, 拍動比を狭く, 拍動数の少ないものとした。(3) ミルクジャーの位置を1450から1200mmに下げ, (4) ユニットを3共用型から6専用型とした。(5) 真空ポンプの排気量を380から1,500l/minとし, (6) 真空パイプおよびミルクパイプの口経を大きくした。
搾乳時および水を2.7kg/minの速度で吸わした模凝搾乳時の圧力変動を, 真空ポンプ直近の真空パイプ内, ミルクジャー内およびライナー内で測定したところ, ミルカー更新後は更新前よりも明らかに改善され小さくなった。
更新前後とも, 最も大きな圧力低下は, 乳流出最盛時のライナー内でみられたが, 搾乳速度の早い牛ほどその低下が大きかった。搾乳速度の最も速い牛の例でこの値は, 更新前には設定真空度に対して平均値で200mmHg以上の低下, 平均値に対する最高値および最低値のふれ幅は100mmHgであったが, 更新後のこれらの値は前者で100mmHg, 後者は50mmHgと縮少された。
ジャー内の乳あるいは水を送乳 (水) した時の圧力低下は, ジャー内が他の2点にくらべて大きく, 最大40mmHgであったが, 更新後には30mmHgに減少した。
搾乳牛各個体の搾乳速度は更新後に有意に遅くなったが, マシンストリッピング時間およびその量は更新後に有意に減少した。
14頭の総搾乳所要時間は更新後に短縮され, 2週間目頃からこの傾向は顕著となった。
更新前後2ヵ月にわたってCMTによる乳房炎検査を行ない, 陽性反応分房延数の検査分房延数に対する割合で比較したところ, 前後にその差を認めなかった。
更新前1ヵ月間に4回測定した分房ごとの乳中細胞数の総平均値に対して, 更新後の2週間内では有意に高い平均細胞数を認めたが, それ以後漸減し次の2週間の平均値との間では有意な差を認あなかった。この事は, 乳牛にとってあるいは作業者にとっても, 新しいミルカーに適応するのに若干の日数が必要なことを示唆している。

抄録全体を表示