White Papers

Executive Summary

The demand for automotive turbocharger designs has been falling in recent years, but research and development teams for electric vehicles is on the rise and will also need turbomachinery expertise. Sophisticated cooling systems for EV’s will require much more advanced turbomachinery than internal combustion engine cooling systems. In addition, fuel cell electric vehicles need efficient, high range air compressors. Some methods for improving range are shared in this white paper. Designers of these components will need advanced tools to be successful.

Author: David Schowalter, Ph.D., Concepts NREC

Executive Summary

There are numerous benefits of supercritical carbon dioxide power generation systems, including reduced size and cost. Highly non-linear fluid properties enable the development of unique cycles targeted at specific applications. These fluid properties, however, represent just one of the challenges of designing these systems. Other challenges include increased mechanical stresses, tight manufacturing tolerances, and secondary flow path control.

Reducing the risk of working with supercritical carbon dioxide is a key factor for successful projects. Firstly, appropriate tools for cycle and component design need to address the non-linear fluid properties, specifically. In addition, mechanical considerations such as stability, control, large thrust forces and rotordynamics must also be taken into account. Finally, adequate testing will always play a role. Addressing these considerations early in the design and development process will improve the likelihood of a winning supercritical CO2 endeavor.

Author: Peter Klein, Director CAM Software, Concepts NREC

When designing bladed rotating components, engineers often use ruled-surface blades with the goal of making a shape that is easily manufactured on a milling machine. These blades can be quickly machined in one pass using the side of a cutting tool (see Figure 1). This process is often referred to as “flank milling.” The alternative is to make many passes cutting with the tool tip, a process known as “point milling”. For the right application flank milling is favored for shorter cutting times and better surface quality. However, the ruled data should be well conditioned and several pitfalls should be avoided during the design and construction process.

Authors:  Mark R. Anderson, Carlos Felipe F. Favaretto, Concepts NREC

Casing treatment was first developed to extend the range and off design performance of centrifugal compressors in turbocharger applications. Tighter regulations on exhaust gas emissions from vehicles have driven the development of smaller, turbocharged engines. The technology is now gaining increasing attention in other industries that share many of the same requirements.   This paper examines the design process for casing treatment in detail using specialized turbomachinery software from Concepts NREC’s Agile Engineering Design® suite for preliminary design modeling and optimization.