Propulsion Systems

Materials Research & Design (MR&D) specializes in the design and analysis of advanced motor and engine components for air breathing, liquid rocket and solid rocket applications. Our experience spans from conventional turbofan engines to high performance missile nozzles to heavy lift liquid fuel engines. Our in-house materials database and proprietary micro-mechanics codes enable us to tailor advanced material systems for the extreme environments in which these components must operate. The design phase flows into test design, pretest predictions and post test data correlation resulting in final components with an excellent track record of success. MR&D will help you bring the next generation of Propulsion Systems to market on time and under budget.

Large Scale Ceramic Matrix Composite (CMC) Nozzle Extension

MR&D has developed a CMC Nozzle Extension which improves manufacturability and engine integration while also significantly reducing mass. Although composite nozzle extensions have been successfully integrated with existing engines in the past, MR&D’s developments have the potential to offer significantly improved performance and reduced mass at a lower cost. Additionally, our design can be fabricated domestically. Ongoing efforts include developing large scale nozzle extensions manufactured via involute, gore, and tape wrap layups with and without enhanced erosion resistance. MR&D supports these efforts through design and analysis of full scale nozzle extensions and subcomponents as well as test design, pre-test predictions and post test data correlation. MR&D is positioned to help you extend the capabilities of tomorrow’s engines within the confines of today’s budgets and schedules.

Turbofan Inlet Cowl

MR&D was tasked to identify the effects that manufacturing defects have in a composite inlet cowl. MR&D investigated both layered shell and 3D solid elements to correlate the finite element model with test data. Simulations were then used to predict the performance of the component under more complex operating conditions. White light data was utilized to generate a detailed finite element model with exact dimensions, thickness variations and explicitly defined resin rich regions. The ability to model the as-manufactured part, complete with defects, resulted in an accurate assessment of the actual hardware, thereby reducing manufacturing costs associated with defect remediation or outright part rejection.

As-Manufactured Inlet Cowl (Top) & MR&D Finite Element Model (Bottom)

Turbojet Transition Duct

MR&D worked in conjunction with NASA Langley to design and analyze a CMC turbojet transition duct. The objective was to develop a design capable of transitioning from a C-C duct at one end to a metallic duct box at the other end. The major issue was accommodating the thermal expansion differences between the materials with minimal exhaust gas leaking. The experience from this program served as the basis for solving the similar but more complex problems with the CMC nozzle extensions noted above.

CMC Exhaust Duct

MR&D was tasked to determine the parameters of a CMC nozzle for use in a hypersonic cruise environment and provide potential performance improvements over existing metallic exhaust nozzles. Use of CMCs in an exhaust duct offers a number of advantages over a metallic design, such as reduced weight and improved re-usability. Whereas the hypersonic vehicle is designed to be used only once, the scramjet engine is tested multiple times prior to flight and therefore a reusable CMC exhaust duct offers cost advantages. MR&D separately sized the thicknesses of OML C-C and IML C-ZrC / C-C nozzle walls based on membrane loads and a specified unsupported length. Shear and thermal buckling analyses, thrust load, thermal stresses due to max thermal gradient, and acoustic loads were all utilized to determine the thickness for CMC exhaust duct components. Ultimately, the CMC design provided areal weight savings of ~40% over the existing metallic exhaust duct. Weight savings resulted from the load bearing capability of CMC TPS materials while the re-usability of CMCs provided added cost savings.