Each impeller has a diameter, D, a blade width W, and an off bottom clearance C. Agitation is created within the tank by the action of an impeller or impellers, turning at the shaft speed, N. In addition to solid, constant diameter shafts, agitators may have stepped diameter or even hollow shafts. This shaft must transmit torque, withstand bending moment and not operate at a speed close to its natural frequency. The power is transmitted to the impeller or impellers by a shaft, with diameter d and extension L from the mounting surface. Some agitators are mounted on open-top tanks, and do not have a seal. This may be a lip seal, packing or various types of mechanical seals. In many cases, the agitator is mounted on a closed top tank, so it will have a shaft seal. These duties are normally best served by using a gear drive specifically designed for agitator service, rather than a standard speed reducer. This reducer, in addition to reducing speed and increasing torque, must usually support all of the shaft loads, which include not only torque, but bending moment, downward load (weight) and pressure thrust in a closed tank. Therefore, the power is transmitted through a speed reducer, which is normally a gear drive. In most cases, (except in small tanks, typically less than 2000l capacity) motor speed is too high to drive the shaft directly. Most commonly, agitators are fixed speed, though multispeed motors or variable speed drives may be used where there is a need to change speed during different parts of the process, a desire to fine-tune results, or simply to minimize energy consumption. Though any device which provides rotary power can in principle be used (the author has seen such things as hydrostatic drives, steam turbines and internal combustion engines used), the most common prime mover is the simple electric motor. Power is provided by means of a prime mover.
![agitator design handbook pdf agitator design handbook pdf](https://d3525k1ryd2155.cloudfront.net/h/725/494/854494725.0.m.jpg)
Note that the term agitator refers to the entire machine some people incorrectly use this term to apply to the impellers only. Let us follow the flow of power through the system, identifying the nomenclature and standard symbols as we do so. To begin, it is useful to identify the major components of an agitated tank, as shown in Figure 1. We will also cover the basics of heat transfer calculations. Likewise, mechanical design is not covered, both due to time limitations and the availability of such information in more generic agitation courses.Ĭhapter One: Agitator Design Basics In this section, we will cover nomenclature, standard symbols, basic concepts, principle dimensionless numbers and the main classifications of flow patterns. Solids suspension is not covered, as serious solids suspension applications are rare in these industries, and are covered in more generic agitation courses available in the marketplace.
![agitator design handbook pdf agitator design handbook pdf](https://demo.fdocuments.in/img/378x509/reader023/reader/2020111503/552cb7554a7959047d8b477c/r-1.jpg)
An introduction to advanced tools such as Computational Fluid Mixing (CFM) is given, and sanitary design issues are addressed.
![agitator design handbook pdf agitator design handbook pdf](http://patentimages.storage.googleapis.com/US6715913B2/US06715913-20040406-D00002.png)
#Agitator design handbook pdf how to#
Considerable time is devoted to fermenter and bioreactor design, including how to pilot in such a way as to get the kind of data which is useful for agitation scale-up and energy cost minimization.
![agitator design handbook pdf agitator design handbook pdf](https://www.mdpi.com/processes/processes-08-00955/article_deploy/html/images/processes-08-00955-g009.png)
The course begins with a basic introduction to agitation terminology and principles, then progresses through design concepts for liquid motion, gas dispersion and scale-up. A basic Introduction to general agitator design principles is given, but the focus is primarily on applications found in the Pharmaceutical/Bioprocessing Industries. The application technology ranges from simple to complex, and the construction details range from standard to highly sanitary. Typical applications in these industries might include, for example, simple tanks containing CIP solutions, broth and slurry tanks, compounding tanks and fermenters/bioreactors. Introduction This course is intended to aid those in the bioprocessing, pharmaceutical and food industries who must specify, purchase, operate, troubleshoot or perform research involving agitation equipment. Benz Copyright Benz Technology International, Inc. Agitator Design Principles for Pharmaceutical and 1 of 129Īgitator Design Principles for the Bio/Pharm Industries Gregory T.