自動攪拌一體車,是一種帶有葉片的軸在圓筒或槽中旋轉,將多種原料進行攪拌混合,使之成為一種混合物或適宜稠度的機器。今天我們為大家介紹一下的攪拌機工作原理:
The automatic mixer truck is a kind of machine with blades rotating in the cylinder or tank to mix various raw materials into a mixture or suitable consistency. Today, we will introduce the working principle of the mixer
攪拌機是由多個參數決定的,用任何一個單一參數來描述一臺攪拌車是不可能的。軸功率(P)、槳葉排液量(Q)、壓頭(H)、槳葉直徑(D)及攪拌轉速(N)是描述一臺攪拌車的五個基本參數。槳葉的排液量與槳葉本身的流量準數,槳葉轉速的一次方及槳葉直徑的三次方成正比。而攪拌消耗的軸功率則與流體比重,槳葉本身的功率準數,轉速的三次方及槳葉直徑的五次方成正比。
Mixer is determined by many parameters. It is impossible to describe a mixer with any single parameter. Shaft power (P), blade discharge (q), head (H), blade diameter (d) and stirring speed (n) are the five basic parameters to describe a mixer. The discharge volume of the blade is directly proportional to the flow standard of the blade itself, the first power of the blade speed and the third power of the blade diameter. The shaft power consumed by stirring is directly proportional to the specific gravity of the fluid, the power criterion of the blade itself, the third power of the rotating speed and the fifth power of the blade diameter.
在一定功率及槳葉形式情況下,槳葉排液量(Q)以及壓頭(H)可以通過改變槳葉的直徑(D)和轉速(N)的匹配來調節,即大直徑槳葉配以低轉速(保證軸功率不變)的攪拌車產生較高的流動作用和較低的壓頭,而小直徑槳葉配以高轉速則產生較高的壓頭和較低的流動作用。在攪拌槽中,要使微團相互碰撞,解決的辦法是提供足夠的剪切速率。
Under the condition of certain power and blade form, the discharge volume (q) and head (H) can be adjusted by changing the matching of diameter (d) and speed (n) of blades, that is, large diameter blades with low speed (ensuring the same shaft power) produce higher flow effect and lower head, while small diameter blades with high speed produce higher head and lower head Mobility. In the stirred tank, the solution is to provide enough shear rate to make the micro clusters collide with each other.
自動上料攪拌機
Automatic feeding mixer
從攪拌車原理看,正是由于流體速度差的存在,才使流體各層之間相互混合,因此,凡攪拌過程總是涉及到流體剪切速率。剪切應力是一種力,是攪拌應用中氣泡分散和液滴破碎等的真正原因。必須指出的是,整個攪拌槽中流體各點剪切速率的大小并不是一致的。通過對剪切速率分布的研究表明,在一個攪拌槽中至少存在四種剪切速率數值,它們是:就槳葉區而言,無論何種漿型,當槳葉直徑一定時,剪切速率和平均剪切速率都隨轉速的提高而增加。
From the principle of mixer truck, it is the existence of fluid velocity difference that makes the fluid layers mix with each other. Therefore, the shear rate of fluid is always involved in the mixing process. Shear stress is a kind of force, which is the real cause of bubble dispersion and droplet breakup in stirring applications. It must be pointed out that the shear rate of fluid in the whole stirred tank is not the same. The results show that there are at least four shear rate values in a stirred tank. They are as follows: for the blade region, the shear rate and average shear rate increase with the increase of the rotating speed, regardless of the size of the impeller.
但當轉速一定時,剪切速率和平均剪切速率與槳葉直徑的關系與漿型有關。當轉速一定時,徑向型槳葉剪切速率隨槳葉直徑的增加而增加,而平均剪切速率與槳葉直徑大小無關。這些有關槳葉區剪切速率的概念,在攪拌車縮小及放大設計中需要特別當心。因小槽與大槽相比,小槽攪拌車往往具有高轉速(N)、小槳葉直徑(D)及低葉尖速度(ND)等特性,而大槽攪拌車往往具有低轉速(N)大槳葉直徑(D)及高葉尖速度(ND)等特性。
However, when the rotating speed is constant, the relationship between the shear rate and the average shear rate and the blade diameter is related to the pulp shape. When the rotating speed is constant, the shear rate of radial blade increases with the increase of blade diameter, but the average shear rate has nothing to do with the blade diameter. These concepts about the shear rate in the blade zone need to be taken care of in the design of the mixer. Compared with the large tank, the small tank mixer often has the characteristics of high speed (n), small blade diameter (d) and low blade tip speed (nd), while the large tank mixer often has the characteristics of low speed (n), large blade diameter (d) and high blade tip speed (nd).