Design And Experimental Study Of Seabuckthorn Infrared Hot Air Drying Oven

Seabuckthorn has high medicinal and edible value.Drying is an essential link in the processing of seabuckthorn.The quality and efficiency of drying directly affect the quality of finished seabuckthorn.However,the existing seabuckthorn drying technology and equipment are still in the primary stage,and most of them are dried by experience.There is a lack of a set of relatively scientific drying technology and equipment,which restricts the development of seabuckthorn industry.Aiming at the problems of low drying efficiency and poor drying quality of seabuckthorn caused by unclear mechanism and poor working parameters of the existing drying device,in order to further explore the drying mechanism of seabuckthorn and optimize the working parameters of the drying device,an infrared hot air combined drying device based on temperature and humidity control is designed,the structure and key components of the whole machine are designed and optimized,and the performance of the drying device is verified by simulation analysis and experimental research,A set of high-efficiency and high-quality drying process for seabuckthorn is proposed,which provides theoretical guidance for large-scale drying of seabuckthorn.The main research contents are as follows:(1)The material characteristics of fresh seabuckthorn were studied.The structural dimension of seabuckthorn is measured,which provides data support for the design of material tray in drying oven;The initial moisture content and color characteristics of seabuckthorn were tested,and the initial moisture content and color parameters of fresh seabuckthorn were obtained,which provided a theoretical basis for the subsequent drying oven design,parts selection and prototype test.(2)An infrared hot air drying oven for seabuckthorn was designed.At present,seabuckthorn has the problems of poor drying quality and low drying efficiency.According to the measured characteristic parameters of seabuckthorn materials,an infrared hot air drying oven based on temperature and humidity control is designed,the basic structure and working principle of the drying oven are described,and the key parts and internal circulation structure are designed and studied to determine the relevant design parameters.(3)The flow field uniformity of the drying oven was optimized.The method of combining Computational Fluid Dynamics simulation analysis with actual wind speed measurement is used to adjust the flow field uniformity of the drying oven and determine the height of the air equalizing plate.Finally,it is determined that after adjusting the height of the upper and lower five layers of air equalizing plates to 1.5 mm,6 mm,10 mm,12 mm and 15 mm respectively,the uniformity coefficient of the dry layer reaches 97.15%,and the flow field of the five layers of dry layer is basically uniform.(4)The prototype test of seabuckthorn infrared hot air drying oven was carried out.The effects of temperature and relative humidity on the drying quality of seabuckthorn were studied by taking drying rate,color and rehydration ratio as evaluation indexes.In a certain temperature and humidity range,according to the test results,the best working parameter combination is determined as follows: temperature 70?,relative humidity 20%.The results showed that the drying time was 8 h and the color difference value ?E is 3.85 and rehydration ratio is 1.277.The performance of the drying oven achieves the expected effect.Using the same working parameters,the drying efficiency and quality of the infrared hot air drying oven designed in this paper are better than that of single hot air drying.