农业工程学报
農業工程學報
농업공정학보
2014年
7期
236-242
,共7页
粮食%干燥%水分%干燥动力%解析法
糧食%榦燥%水分%榦燥動力%解析法
양식%간조%수분%간조동력%해석법
grain%drying%moisture%the force of drying%exergy%analytical method
为揭示粮食中水分蒸发耗能特征,基于不可逆热力学分析方法,把水分迁移的现象看作是一定数量的能量迁移,建立水分结合能解析模型,给出了水分结合能随温度、含水率变化规律,清晰地呈现了粮食在高水分段水分蒸发受物料的限制作用很小,而在低水分段水分结合能随温度升高显著降低的特征,研究结果为解析粮食二段降速干燥过程、合理匹配干燥温度提供了依据和分析方法,为揭示干燥质驱动机理,制订科学的能效评价标准,合理的干燥装备系统设计补充了技术基础理论。
為揭示糧食中水分蒸髮耗能特徵,基于不可逆熱力學分析方法,把水分遷移的現象看作是一定數量的能量遷移,建立水分結閤能解析模型,給齣瞭水分結閤能隨溫度、含水率變化規律,清晰地呈現瞭糧食在高水分段水分蒸髮受物料的限製作用很小,而在低水分段水分結閤能隨溫度升高顯著降低的特徵,研究結果為解析糧食二段降速榦燥過程、閤理匹配榦燥溫度提供瞭依據和分析方法,為揭示榦燥質驅動機理,製訂科學的能效評價標準,閤理的榦燥裝備繫統設計補充瞭技術基礎理論。
위게시양식중수분증발모능특정,기우불가역열역학분석방법,파수분천이적현상간작시일정수량적능량천이,건립수분결합능해석모형,급출료수분결합능수온도、함수솔변화규률,청석지정현료양식재고수분단수분증발수물료적한제작용흔소,이재저수분단수분결합능수온도승고현저강저적특정,연구결과위해석양식이단강속간조과정、합리필배간조온도제공료의거화분석방법,위게시간조질구동궤리,제정과학적능효평개표준,합리적간조장비계통설계보충료기술기출이론。
In order to explore the characteristics of energy consumption for drying grain, the moisture migration potential and its characteristic function in grain were determined by the method of irreversible thermodynamics. Analytical models of moisture binding energy were established by considering the moisture migration as a certain amount of energy transfer. Analytical methods of drying force and quantitative evalution of energy consumption in grain drying were applied to analyze changes of moisture binding energy with temperature and moisture. The result showed that evaporation from grains with high moisture content was little affected by grain features, and moisture could be mostly dried in normal air. Moisture binding energy of grains with low moisture content was significantly decreased with increasing temperature. It indicated that low moisture grain dried at high temperature was inexpensive, on the contrary, increasing the temperature of grain did not improve energy consumption for moisture evaporation in high moisture grain. This study provided valuable information for analyzing the two-stage drying process and drying temperature in grain drying, revealed the driving mechanism of drying mass and the exergy, established exergy transfer model of high moisture grain, analyzed the change laws of exergy value, and proposed a scientific evaluation standard for energy efficiency and the reasonable design of drying system.