Organization of the rational form of air kinetics in chamber for the heat treatment of food products

In this work, the effectiveness of the turbulent (three-dimensional trajectory) kinetics of air in the cargo volume of thermal chambers under recirculation conditions is substantiated analytically and practical tests of heat treatment of food products by convection. The object of research is the aerodynamic parameters of the air in the zone of processing of sausage products and the temperature in their geometric center. Analytical studies of heat exchange processes were carried out on the basis of using a system of differential equations with the involvement of criterion dependencies and similarity theory, and full-scale studies were carried out on a prototype of a heat chamber with an improved air distribution system. As an experimental material, dummies of boiled sausages – sausage casings stuffed with sawdust – were used to fill the working space of the thermal chamber. In the industrial scale experiments boiled sausages “Likarska” were used. To improve air distribution, the aerodynamic network was equipped with specially designed equipment located in the upper part of the chamber symmetrically to its longitudinal axis. Uniform distribution of air along the periphery of the chamber was provided by a double-discharge centrifugal fan an air ducts of equal static pressure, heating was provided by finned bimetallic heat exchangers. Converging pyramidal nozzles on heat exchangers divided the air entering the peripheral channels of the chamber into two flat streams with adjustable aerodynamic parameters for a certain influence of each on the nature of air movement near the product. Its rational three-dimensional movement, characterized by the Reynolds criterion equal to 8200, and the product heating unevenness of 2 degrees Celsius, was formed by nozzles with geometry: air compression angle -18 degrees, proportionality coefficient of compressed air separation on the main and side flows -14, and the degree of freedom of the main flow - 9.09. Thus, the implementation of technical solutions for the organization of three-dimensional air kinetics in a heat chamber under recirculation conditions ensured a sufficiently high uniformity of heat supply to processed products, their quality and safety while reducing the total cost of their production. In addition, the accuracy of engineering calculations when designing air distribution systems.

Gýda ürünlerinin ýsýl iþlemi için haznede rasyonel hava kinetiði formunun organizasyonu

Bu çalýþmada, termal odalarýn kargo hacmindeki havanýn türbülanslý (üç boyutlu yörünge) kinetiðinin devridaim koþullarý altýnda etkinliði, gýda ürünlerinin konveksiyon yoluyla ýsýl iþleminin analitik ve pratik testleriyle kanýtlanmýþtýr. Araþtýrmanýn amacý, sosis ürünlerinin iþlendiði bölgedeki havanýn aerodinamik parametreleri ve geometrik merkezlerindeki sýcaklýktýr. Isý deðiþim süreçlerinin analitik çalýþmalarý, kriter baðýmlýlýklarý ve benzerlik teorisini içeren bir diferansiyel denklem sistemi kullanýlarak gerçekleþtirildi ve geliþtirilmiþ hava daðýtým sistemine sahip bir ýsý odasýnýn prototipi üzerinde tam ölçekli çalýþmalar yapýldý. Deneysel bir malzeme olarak, termal odanýn çalýþma alanýný doldurmak için haþlanmýþ sosislerden (talaþla doldurulmuþ sosis kýlýflarý) maketler kullanýldý. Endüstriyel ölçekte yapýlan deneylerde haþlanmýþ “Likarska” sosisleri kullanýldý. Hava daðýtýmýný iyileþtirmek için aerodinamik að, odanýn üst kýsmýnda uzunlamasýna eksenine simetrik olarak yerleþtirilmiþ özel olarak tasarlanmýþ ekipmanlarla donatýldý. Havanýn odanýn çevresi boyunca düzgün daðýlýmý, çift deþarjlý bir santrifüj fan ve eþit statik basýnca sahip süt kanallarý ile saðlandý, ýsýtma kanatlý bimetalik ýsý eþanjörleri ile saðlandý. Isý eþanjörleri üzerindeki yakýnsak piramidal nozullar, odanýn çevresel kanallarýna giren havayý, her birinin ürünün yakýnýndaki hava hareketinin doðasý üzerinde belirli bir etkisi için ayarlanabilir aerodinamik parametrelere sahip iki düz akýþa böldü. 8200'e eþit Reynolds kriteri ve 2 santigrat derecelik ürün ýsýtma eþitsizliði ile karakterize edilen rasyonel üç boyutlu hareketi, geometriye sahip nozullar tarafýndan oluþturulmuþtur: hava sýkýþtýrma açýsý -18 derece, basýnçlý hava ayýrmanýn orantýsal katsayýsý. ana ve yan akýþlarda -14 ve ana akýþýn serbestlik derecesi - 9.09. Bu nedenle, termal odadaki havanýn üç boyutlu kinetiðinin devridaim koþullarý altýnda düzenlenmesi için teknik çözümlerin uygulanmasý, iþlenmiþ ürünlere ýsý tedarikinde yeterince yüksek bir homojenlik, bunlarýn kalitesi ve güvenliðini saðlarken ayný zamanda genel maliyetleri azaltýr. iþlem. Ayrýca termal ekipmanlarda hava daðýtým sistemleri tasarlanýrken mühendislik hesaplamalarýnýn doðruluðu arttýrýlýr.