Flow modeling speeds processing, lowers costs.

If you are on the lookout to lower your costs--and who isn't--think about flow modeling. Flow modeling can help bring better products to market while lowering development costs. It can optimize processing equipment for specific applications.

Flow modeling software, also known as computational fluid dynamics (CFD), can create a virtual prototype of a product or process that simulates real-world conditions. You get detailed predictions of flow velocity, temperature and species concentrations for almost any piece of processing equipment. Once created and validated, these virtual prototypes can be used to investigate a variety of design configurations, optimize manufacturing process parameters and conduct safety studies.

If you can troubleshoot the manufacturing process, correct defects and improve quality using software rather than on the plant floor, you can reduce the length of product development cycles and improve manufacturing processes. State-of-the-art flow modeling programs analyze complex flow and heat transfer problems, such as those involving viscoelastic materials, multiple phases, complex chemical reactions, microbial kinetics, mixing-related phenomena and intricate equipment geometries.

The widespread availability of powerful, inexpensive computers and advances in modeling software have led to commercial software that is reliable, cost-effective and easy to use, as well as customizable for specific applications. The advances in flow modeling have been driven by the tremendous need for analysis, design and optimization of complex equipment in the processing industries.

Flow modeling has evolved into a key component in the design and scaleup of unit processes, bringing about large improvements in process efficiency and product quality. For example, flow modeling can predict the performance of alterations made to an extrusion die design, eliminating the need for expensive die modifications and long trials on production equipment. Or CFD can be harnessed to improve nearly any type of mixer.

In twin-screw extrusion, the screw profile consists of kneading blocks, forward-pumping elements and reverse-pumping elements in a particular sequence. Designing a screw profile for a new product can be challenging. Modeling can determine the design that produces the desired level of mixing, pressure increase or decrease, and residence time. Flow details can determine the mixing effectiveness of the kneading block configuration. Similarly, flow modeling can map the performance of each screw section and aid in developing new screw profiles.

In mixing applications, use CFD to help understand the flow patterns and the circulation time characteristics of a mixer design and liquid material. If there are solids in the system, the simulation can help determine which vibration frequency and amplitude to use to keep the solids in suspension. Further information. Kumar Dhanasekharan, Fluent Inc., 10 Cavendish Ct., Centerra Resource Park, Lebanon, NH 03766; phone: [phone]; fax: [phone]; URL: http://www.fluent.com.