The Design Of Natural Cold Source Of Preservation System For Preservation Storage

With the continuous development of fruit and vegetable industry,people's demand for fruits and vegetables and their quality requirements simultaneously increased.Fruit and vegetable are difficult to store and its perishable,preservation storage can effectively reduce the loss of fruit and vegetable through the storage process.In order to determine the optimal environmental conditions for preservation of fruits and vegetables,fruit and vegetable preservation storage can still maintain the best quality.Combined with the Shenyang Municipal Science and Technology Program project "Hanfu Apple's mobile automatic monitoring and forecast storage and preservation of the library" content.In this paper,the numerical simulation of the actual preservation of the calculation and analysis,and the wireless temperature and humidity monitoring system of preservation was designed.As the Hanfu apple as an object do the storage test research,the results of the study are as follows.(1)The present situation analysis of fruits and vegetables preservation storage fresh technology,numerical simulation technology and wireless monitoring system.Based on the analysis of the present situation of the development of the fruits and vegetables preservation storage fresh technology,the technology of the numerical simulation and temperature and humidity wireless monitoring system are studied.The method of numerical simulation and temperature and humidity wireless monitoring system was used to improve the storage of fresh fruits and vegetables Environment,to enhance the quality of fruit and vegetable storage.The combination of temperature and humidity wireless monitoring system and numerical simulation technology method are proposed,improving the fruit and vegetable preservation storage environment and enhancing the quality of fruit and vegetable.(2)Structural design and numerical simulation analysis of preservation storage.On the basis of the design of the preservation storage structure,the velocity field of three different apple boxes in the preservation storage is simulated and analyzed,and the two-dimensional velocity vector diagram of different positions is obtained.The results show:Apple box before and after the interval of 3cm,left and right interval of 5cm placed in the way,having the distribution of uniform airflow and a large return flow whirlpool,is conducive to the loss of the apple box due to the effect of apple respiration heat.(3)Design of wireless temperature and humidity monitoring system for preservation storage.Based on the NRF24L01 + wireless communication module,the system mainly includes monitoring and control,data transmission and PC monitoring three units.Software design using modular programming ideas,achieving the main program calls the module subroutine.The combination of hardware system design and software system programming can achieve temperature and humidity parameters of the wireless precision monitoring for preservation storage.In addition to achieve the main temperature and humidity monitoring function,but also the temperature and humidity data can be observed outside for preservation storage.Reduce interference within the operating personnel to the preservation system,convenient for operator to observe temperature and humidity data.The system has reliable communication,low cost,has the advantages of a certain accuracy of measurement.(4)Preservation storage system operation and preservation quality verification.The Hanfu apple picking from Shenyang Agricultural University scientific research base,doing a reasonable display according to the results of the numerical simulation,and running the wireless temperature and humidity monitoring system,the system operation effect test and fresh quality test are done.The results show:Compared with the temperature and humidity data measured by the temperature and humidity recorder,the maximum error of temperature and humidity under the wireless temperature and humidity monitoring system are ± 0.2 ?and 0.4%respectively,and temperature and humidity can be controlled within the scope of the error of the requirements,meet the requirements of actual storage;After 10 weeks of operation,the average weight loss rate of Hanfu apple was 1.9%,the peel and flesh color were increased by 11%and 8%respectively,and the overall chewiness and pulp chewing were decreased by 18.59%and 21.53%respectively.Show that the long-term stable running status of preservation storage system,Hanfu apples after storage,the apple quality is better.