基于閉式熱泵沸騰床干燥器流化特性與干燥的CPFD數值模擬

摘 要：采用閉式熱泵沸騰床干燥器可在高效干燥的同時實現干燥介質除濕、加熱循環再利用，又因其結構相對較為簡單，易于實現工業化放大。為能夠進一步地探究其顆粒的流化特性和干燥過程，基于計算流體力學Barracuda CPFD理論方法，以典型農副產品胡蘿卜顆粒為例，對閉式熱泵沸騰床干燥器中胡蘿卜顆粒的流化特性和干燥過程進行數值模擬計算及分析。通過對比CPFD的模擬計算數據及同等條件下的實驗數據可知，Ganser曳力模型能夠較為準確地預測胡蘿卜顆粒在沸騰床中的流化特性和干燥效果。該文驗證CPFD的數值計算方式能夠準確地預測閉式熱泵沸騰床干燥器內部的顆粒流化特性和干燥過程，具有十分廣大的應用前景，為同類型的沸騰床干燥器的工業級放大的研究以及新型閉式熱泵沸騰床干燥器的工藝設計和參數調配提供可靠的指導。

關鍵詞：閉式熱泵沸騰床；流化特性；CPFD；干燥；胡蘿卜顆粒；曳力模型

中圖分類號：TQ02 文獻標志碼：A 文章編號：2095-2945（2024）29-0027-07

Abstract： The use of a closed heat pump fluidized bed dryer can achieve dehumidification， heating and recycling of the drying medium at the same time of efficient drying， and because of its relatively simple structure， it is easy to realize industrial scale-up. In order to further explore the fluidization characteristics and drying process of carrot particles in a closed heat pump fluidized bed dryer， the fluidization characteristics and drying process of carrot particles in a closed heat pump fluidized bed dryer were numerically simulated and analyzed based on Barracuda CPFD theory. By comparing the simulation data of CPFD and the experimental data under the same conditions， the Ganser drag model can accurately predict the fluidization characteristics and drying effect of carrot particles in the fluidized bed. This paper verifies that the numerical calculation method of CPFD can accurately predict the particle fluidization characteristics and drying process in the closed heat pump fluidized bed dryer， which has a very broad application prospect， and provides reliable guidance for the industrial scale-up study of the same type of fluidized bed dryer and the process design and parameter allocation of the new closed heat pump fluidized bed dryer.

Keywords： closed heat pump fluidized bed; fluidization characteristics; CPFD; drying; carrot particles; drag model

干燥技術作為農業生產過程中的一項重要技術，在我們的生產、生活中都有著重要作用，在農業、化工、食品等行業中的應用至關重要，涉及領域十分廣泛，在國民經濟發展中有著舉足輕重的作用[1]。干燥技術在延長產品的儲存時間和提高糧食質量等方面發揮重要作用。糧食的干燥利用熱質交換的原理，使糧食中的水分逐步減少，這個過程中涉及熱力學、生物學、化學和流體力學等學科的交叉融合，是一項十分復雜的生產加工技術[2]?！?br>