Design of a Linerless Cryogenic Propellant Tank for a Small Payload Launch Vehicle
The need of lightweight launch vehicles that will reduce the cost and make ﬂights more frequent into orbit has called for an increase of composite materials in the aerospace industry. Composite material’s low thermal conductivity, high resistance to fatigue, and most importantly, low-weight can greatly reduce the cost of launch operations by decreasing the overall weight of the vehicle. Weight and cost savings are critical because any amount of weight that is saved can be directly applied as an additional amount of payload capability. The tanks on space vehicles are pressurized vessels that store fuel at cryogenic temperatures and have generally been either entirely manufactured or lined with metals. In most cases the tanks are the main structure of the vehicle which consequently can become the heaviest component. These vehicle tanks are exposed to extremely cold temperatures and gravitational loads that weaken the material and could potentially cause a fuel leak. Carbon ﬁber polymer matrix (CFRP) composite materials are a promising option for replacing conventionally used metal in cryogenic tank structures. Therefore, the understanding of composite materials under cryogenic exposure is essential for the next generation of spacecraft propellant tanks. The ﬂexural behavior of plain-woven carbon ﬁber and plain-woven Kevlar ﬁber with Epon 828/ Epikure 3015 curing agent is studied as a potential commercially available material system for application in cryogenic tanks. Samples were exposed to cryogenic temperatures at one surface and to room temperature at the other surface to mimic a realistic environment that the tanks will be exposed to. Carbon and Kevlar ﬁber with epon/epikure material system for pressure vessels are an ideal material selection for cryogenic tank applications. Most current analysis only concentrate on testing materials entirely under cryogenic temperatures, or room temperature. Many fail to consider the small, but impactful temperature gradient caused by the low temperature propellant and ambient temperature on either side of the tank walls.
Torres, Itzel A, "Design of a Linerless Cryogenic Propellant Tank for a Small Payload Launch Vehicle" (2020). ETD Collection for University of Texas, El Paso. AAI27995605.