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山陽小野田市立山口東京理科大学（本学）は，2021年度に文部科学省「数理・データサイエンス・AI教育プログラム認定制度（リテラシーレベル）」及び「数理・データサイエンス・AI教育プログラム認定制度（リテラシーレベル）プラス」に選定された．また，2023年4月には，工学部に数理情報科学科（仮称）を新設予定であり，データサイエンス教育の充実化を図っている．データサイエンスでは統計や機械学習を用いた分析が必要であり，プログラミングのスキルは必須である．本講義で導入したGoogle Colaboratoryは，Pythonをブラウザから実行できるアプリケーションで，無料で利用可能，環境構築不要，機械学習やディープラーニングの環境の構築が可能，CPU及びGPU環境を利用可能などの多くの利点を有する。現在プログラミングの講義がない応用化学科の学生に対してプログラミングへの抵抗を少しでも和らげ，興味を喚起するために，1コマと少ない回数ではあるが，担当講義である分析化学においてGoogle Colaboratoryによるプログラミングの回を取り入れた．本稿ではGoogle Colaboratoryを使用した図表の作成内容及び講義終了後のアンケート結果について報告する．

Cross-flow boiling in horizontal tube bundles occurs in kettle type evaporators. Convective heat transfer due to the motion of vapor bubbles is an important factor for boiling heat transfer in the evaporator under low heat flux conditions. To clarify the liquid agitation effect on heat transfer, the local heat transfer around a tube in in-line and staggered tube bundles was investigated in two-phase flows under adiabatic and atmospheric pressure conditions. Air and tap water were used as the working fluids. The test section was a vertical duct with inner dimensions of 90 x 90 mm2. In-line and staggered tube bundles each containing eight rows and five columns, were used as test sections. For both bundles, the tube diameter, d, was 18 mm, and the tube pitch, p, was 22.5 mm (p/d = 1.25). The local heat transfer had the highest values around θ = ± 90° where the liquid velocities were high in single-phase, bubbly and intermittent flows for both in-line and staggered arrays. A significant improvement in the heat transfer caused by the bubble motion was present for the in-line array as compared to the staggered array. Owing to the fluctuation of the liquid velocity, the heat transfer coefficient fluctuated significantly under intermittent flow conditions. In the bubbly flow at p/d = 1.25, the average heat transfer coefficient around a tube for the in-line array was higher than that for the staggered array. In contrast, the heat transfer coefficient of the staggered array was high under intermittent flow at a lower gas flow rate. This tendency is different from the results at p/d = 1.5. With a decrease in the relative size between the bubble diameter and the tube gap, there was a high improvement in the heat transfer coefficient due to the liquid agitation in the bubbly flow.

A falling film evaporator can reduce the amount of refrigerant compared with a flooded evaporator. Required functions for the heat transfer surface in falling liquid film evaporation are thin liquid film formation without breaking at low heat flux, nucleate boiling promotion in liquid film, and suppression of liquid entrainment at high heat flux. In this study, a porous thermal spray coating using copper as the coating material was made on a copper cylinder. The heat transfer performance of falling film evaporation and pool boiling was evaluated using HFO1233zd(E) as the refrigerant, and the obtained results were compared with those for HFC-134a. The test cylinder was heated by a cartridge heater inserted at the center. Falling film evaporation experiments had been conducted with a film mass flow rate of 3.3×10-2 kg/(m·s), heat flux of 10 to 85 kW/m2, and a saturation temperature at 20 ºC. The effects of the thermal spray coating, heat flux and thermo-physical properties of the refrigerants on heat transfer performance were investigated. The heat transfer coefficient increased with increasing heat flux. For the thermal spray coating, a large hysteresis effect according to the heating procedure with increasing or decreasing heat flux was observed in the characteristics of the heat transfer coefficient. The heat transfer enhancement factor by the thermal spray coating was up to 4.8. The value was higher than that for HFC-134a, especially under high heat flux condition. In the comparison between pool boiling and falling film evaporation heat transfer, falling film produced higher heat transfer coefficients for the thermal spray coating while the heat transfer on the smooth surface deteriorated due to partial dryout. The fine porous structure enhanced liquid spreading by the capillary force and evaporation from the liquid film surface by vapor bubble agitation.