The Research Of The Temperature Distribution Characteristics During The Process In Bulk Curing Barn

Bulk curing barn has many good benefits,such as forced ventilation,hot air circulation,automated or semi-automated control of temperature and humidity.It is widely used in our country.But the short time bulk curing barn applied and the research of its temperature distribution is not deep enough.This is likely to cause unreasonable distribution of tobacco,and lead to poor quality of tobacco.This article has been studied for temperature distribution of Yunyan No.85 baking process.Real-time temperature of 12 or 18 key points of barn is measured by thermometer and recording such data.These data are used to analyze the influence of some factors on temperature distribution,such as different flow direction,different clamping methods of tobacco,and different methods of woven together and other factors.These analyzes are for ascertaining the temperature distribution of barn in different ways,thus reasonably determine the spatial distribution of tobacco and accurately grasp the tobacco curing process.It is very important to improve the crafts of bulk curing process and the quality of tobacco.The main findings are as follows.1.In the Most of time,the temperature of the airflow decrease barn,which is included the average temperature,the maximum temperature and the minimum temperature,is higher than the corresponding values of air rising barn.The maximum temperature difference between airflow decrease barn ceiling and air rising barn is 1.3oC.2.The maximum temperature area of the air rising barn moves backward with baking and ultimately it is stable in the middle area of the barn.The lowest temperature area of the air rising barn is located at the ceiling end area in the period of tobacco yellow,and it is located at the front of ceiling in the period of determine color and dry.The maximum temperature area of the airflow decrease barn moves forward with baking and ultimately it is stable in the front area of the barn.The lowest temperature area of the airflow decrease barn is located at the ceiling middle and back area.3.Most of the time,the value between temperature maxima and temperature minima of air rising barns is less than the corresponding value of airflow decrease barns,and the maximum is 3.50 C.The average temperature difference of air rising barn section is less than the corresponding value of airflow decrease barn.In the horizontal direction,temperature distribution difference of the air rising barn is more uniform than the airflow decrease barn.4.Maximum and minimum temperatures of the hanging rod type barn are higher thanthe cage type barn.The maximum temperature difference and the minimum temperature difference are 2.50 C and 4.80 C.Difference between the maximum value and the minimum value of hanging rod type barn is lower than the cage type barn in the most time,and continuously increased to 2.30 C.5.Most of the time,the value between temperature maxima and temperature minima of the hanging rod type barn is higher than the corresponding value of the cage type barn;the maximums of the ceiling and the bottom shelf are 1.70 C.The average temperature difference of the hanging rod type barn is higher than the corresponding value of the cage type barn.In the horizontal direction,temperature distribution difference of the cage type barn is more uniform than the hanging rod type barn.6.Maximum and minimum temperatures of the hanging rod type barn are higher than the cage type barn,and it is up to 2.40 C.Difference between the maximum value and the minimum value of the hanging rod type barn is lower than the cage type barn in the most time.In the vertical direction,temperature difference of the hanging rod type barn is smaller,and it is conducive to bake.7.Heat utilization of three series of tobacco is higher than two and four.Temperature distribution of three series tobacco is more uniform both vertical or horizontal direction,and it provides a better curing environment.