| Summary: | 碩士 === 國立臺北科技大學 === 能源與冷凍空調工程系碩士班 === 97 === Because the thermal radiation vacuum freezing-drying method compares in the partial freezing and it has the advantage of fast merit; when collecting and reading related information, and some literature discusses to be the desired dry material by milk, and perform vacuum freeze-drying. Therefore the present paper depends on the literature to carry on vacuum chamber model of the experiment, and performs numerical simulation by CFD software, and observes heat transfer phenomenon of the internal vacuum chamber.
By the simulation of different conditions, and making the following several conclusions: 1.knowing by the results, the heater and vial flask contacted area conduction to the sample base; But its contacted area''s size is really small regarding the sample base temperature''s influence. 2.In literature milk sample temperature distribution, only case 2.2 and case3.2 has its tendency. 3.Freeze milk sublimation latent heat for - 12542.5W/m3
4.The result and the literature data''s error, its possible reason for the actual freezing and drying process, because the mealy structure which the freeze milk will form dry to reduce the heat conduction. , but the analogue result its sample temperature may maintain at 63~64℃.
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