Structures and Design Phase I Summary for the NASA Composite Cryotank Technology Demonstration Project

Abstract

A description of the Phase I structures and design work of the Composite Cryotank Technology Demonstration (CCTD) Project is in this paper. The goal of the CCTD Project in the Game Changing Development (GCD) Program is to design and build a composite liquid-hydrogen cryogenic tank that can save 30% in weight and 25% in cost compared to state-of-the-art aluminum metallic cryogenic tank technology when the wetted composite skin wall is at an allowable strain of 5000 µin/in. Three Industry teams developed composite cryogenic tank concepts that are compared for weight to an aluminum-lithium (Al-Li) cryogenic tank designed by NASA in Phase I of the CCTD Project. The requirements used to design all of the cryogenic tanks in Phase I will be discussed and the resulting designs, analyses, and weight of the concepts developed by NASA and Industry will be reviewed and compared.

Damage monitoring of polymer-lined carbon fibre-reinforced plastic using small-diameter fibre Bragg grating sensors

“…The applications of CFRP cryogenic tanks have been studied for over the past two decades. [1][2][3][4][5][6][7][8][9] Although the required pressure is low compared with general purpose highpressure vessels, a CFRP tank is exposed to cryogenic temperatures. Moreover, because the curing temperature of high-performance CFRP is approximately 180 C, a difference in the thermal expansions of carbon fibres and resins evolves non-negligible thermomechanical stresses, which were also influenced by the cure shrinkage and vitrification, and tool-part interaction.…”

Structural Design and Sizing of a Metallic Cryotank Concept

“…Three of the four industry teams (Boeing, Lockheed Martin, and Northrop Grumman) were tasked with developing composite cryotank designs. [1][2][3] The NASA team developed an aluminum lithium alloy cryotank design that incorporated Technology Readiness Level 4 (TRL) 9 structural design methodology, materials, and manufacturing techniques to serve as a reference design for comparison to the composite cryotank designs. The reference design was based heavily on the Space Shuttle Super LightWeight Tank 5 (SLWT) and the Ares I liquid hydrogen (LH2) tank.…”

The Application of Carbon Fiber Composites in Cryotank

“…A cost analysis effort showed that 20-25% cost saving can be achieved by utilizing an automated fiber placement process [20].…”

“…NASA worked with four competing industry partners-ATK, Boeing, Lockheed Martin, and Northrop Grumman at the design phase of the project with the aim to reduce weight by 30%, reduce cost by 25%, and withstand a strain of 0.005 [20]. Four competing conceptual designs differing in materials, structures, manufacturing processes were assessed through coupon testing and finite element stress analysis.…”