Laminar and Turbulent Jets Using Ansys Fluent

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In many industrial applications, such as combustors and mixers, the flow introduced into the flow domain is in the form of a jet. A jet, which is a type of free shear flow, is exhaust from a confined source such as a nozzle into the quiescent surrounding. It is generally a stream of flowing fluid that mixes with the surrounding quiescent fluid that is generally at rest. Depending on the cross-section of the exhaust, these jet flows can be planar or round. From an engineering standpoint, the jet centerline velocity, spreading rate, and penetration length are the parameters of interest. Based on the flow properties, jet flows can be laminar or turbulent. Nozzles are designed for maximum efficiency under certain flow conditions by studying these flow behaviors. This can be achieved using computational fluid dynamics (CFD).

In this course, we consider a canonical problem of 2D axisymmetric jet flow to compare laminar and turbulent flow behavior. This SimCafe course was developed by Dr. Rajesh Bhaskaran, Swanson Director of Engineering Simulation at Cornell University, and Lara Camille Backer in partnership with Ansys. It serves as an e-learning resource to integrate industry-standard simulation tools into courses and provides a resource for supplementary learning outside the classroom. In this course, we will learn to set up the models in Ansys Fluent and compare the laminar and turbulent jet flow results. We will also discuss the importance of the k-epsilon turbulence model in this course.

For more ways to learn, check out the Cornell edX course, A Hands-on Introduction to Engineering Simulations at

Cornell University also offers a Fluid Dynamics Simulations Using Ansys online certificate authored by Dr. Rajesh Bhaskaran. Learn more here:

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