为提高离心式水洗茶鲜叶脱水率并实现连续脱水,本研究基于离心式脱水原理,引入风道吹风提高茶鲜叶在脱水过程中的离散度,采用离散场—流场的多相流耦合技术,对茶鲜叶离心脱水过程进行数值仿真模拟,对影响茶鲜叶脱水效果的因素进行研究。研究表明,在确定送风方向的基础上,发现在由离心筒内向外送风的情况下,离心筒与螺旋推进器驱动轴的旋转速度差对脱水效果的影响最大,离心筒转速对脱水效果影响次之,风速对脱水效果影响相对较小。
Abstract
In order to improve the dewatering rate and achieve continuous dewatering, a concept of increasing the dispersion of tea leaves through venting, and using the multiphase flow coupling technology of discrete field - flow field was introduced based on the centrifugal dewatering principle. The centrifugal dewatering process of fresh tea leaves was numerically simulated and verified by experiments to determine the factors affecting the dewatering rate. It was found that the difference of rotational speeds between centrifugal barrel and spiral body had the greatest influence on the dewatering effect in the case that the direction of blowing air was outward from the centrifugal barrel. The centrifugal speed ranked the second on the dewatering effect. The speed of wind had the least effect on the dewatering effect.
关键词
茶叶 /
多相流耦合 /
风道 /
离心脱水
Key words
air duct /
centrifugal dewatering /
multiphase flow coupling /
tea
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基金
国家科技支撑计划(2014BAD06B06)、国家自然科学基金(31201138)