New Investigators Program

The NC Space Grant New Investigators Program is designed to provide seed funding to faculty who are striving to conduct research that is directly aligned with NASA's priorities. This program is primarily focused upon funding investigators who have yet to become established researchers or are attempting to branch out in new directions. By doing so, NC Space Grant contributes to building the intellectual capital and knowledge base of the state of North Carolina.

Self-Sustained Dropwise Condensation PI: Chuan-Hua Chen, Duke University

The objective of this proposal is to explore the feasibility of continuously enhancing dropwise condensation using a self-propelled condensate removal mechanism recently discovered at the PI's lab. During condensation on a superhydrophobic surface, condensate drops spontaneously “jump” out of plane upon drop coalescence, which releases surface energy powering the self-propelled motion. This discovery offers new possibilities in using superhydrophobic surfaces to enhance condensation heat transfer. The self-sustained dropwise condensation is particularly relevant to NASA because of its orientation-independent operation in both high-g launching and low-g orbiting.

Electrostatic Atomization Enhancement of Liquid Sprays for Liquid Propellant Rocket Engines PI: Dr. Tiegang Fang, NC State University

Liquid rocket engines are the primary propulsion systems for launch vehicles and spacecrafts in most cases. The atomization and mixing of liquid fuel and oxidizer play crucial roles in combustion process and determines the combustion efficiency, stability, and heat transfer characteristics. The optimized control of the propellant atomization and mixing is a key objective to achieve. The proposed research focuses on a novel approach to improve the atomization and mixing quality of these swirl atomizers by using an active electrostatic force to control the atomization process during the operation of the liquid rockets. The objective of the project is to fundamentally investigate the liquid breakup and atomization a transient fuel spray from a swirl atomizer under the effect of an electrostatic field. The results will demonstrate the feasibility of an active atomization and mixing control technique. The application of the proposed novel approach in liquid propellant rocket engines can lead to drastic improvements in fuel economy and combustion stability.

Chemical Enrichment of the Young Solar System PI: Dr. Fabian Heitsch, UNC - Chapel Hill

Several chemical elements found on Earth and in meteoritic material suggest that the young solar system has been exposed to a massive stellar explosion ("supernova") during its formation. One of these elements, a radio-active isotope of aluminum, is suspected to play a major role during the early stages of planet formation, when its radio-active decay heats the cores of the young planetesimals. This isotope, together with other elements, is produced during the late stages of a massive star, before its explosion. The explosion then carries the elements far into interstellar space, where they can be integrated into the next generation of young stars. Yet the half-life time of radio-active aluminum is much shorter than the timescales on which stars can form out of interstellar gas. Thus, the supernova must have occurred during the formation of the solar system, and also close-by. The project will investigate the physical mechanisms of injecting trace elements into a young proto-stellar cloud, identifying the conditions that are needed to reach the observed abundances, thus improving our understanding of the formation of Earth-like planets. Physically, this is largely a problem of turbulent mixing, for which the PI's hydrodynamical simulation tool is perfectly suited. The program will provide training to UNC-CH undergraduates in computational physics and fluid dynamics, and the resulting three-dimensional simulations will offer ample opportunities for public outreach programs.

High Temperature Piezoelectric Sensors for Future Propulsion Structure Health Monitoring PI: Dr. Xiaoning Jiang, NC State University

High temperature sensors are in critical need for future propulsion structure health monitoring, turbine engine control and health monitoring, as well as performance and maintainability improvement for power production facilities and other rotary combustion engines. Recently discovered high temperature oxyborate crystals showed stable piezoelectric properties and high resistivity at temperatures close to its melting point (~ 1500° C), which is very promising for high temperature sensor applications. In this project, low profile, highly sensitive high temperature piezoelectric micro-accelerometers will be investigated for structure vibration monitoring at temperatures above 1200° C (or > 2100° F).

Comparative Genomic Analysis of Some Hazard Resistant Deinococcus-Thermus Bacteria PI: Dr. Gaolin Zheng Milledge, NC Central University

Bacteria have been reengineered to produce medicine, clean water, oxygen, and recycle wastes. To explore the Mars, astronauts might want to bring some reengineered bacteria with them. There are many problems associated with engineering bacteria for the Mars exploration. A key need is to identify molecular mechanisms that allow life-forms to survive in harsh conditions. Comparative genomics is a powerful tool to elucidate the molecular mechanisms of observable traits and phenotypes that cannot easily be deduced from the analysis of individual genomes alone. In this project, we will conduct comparative genomic analysis on four Deinococcus-Thermus bacteria that are highly resistant to environmental hazards. Our analysis will include DNA sequences from both coding and non-coding regions (e.g., regulatory motifs, RNA genes, microRNA, structural elements, etc.).

Carolina Bays: a Paleoclimatic Perspective PI: Dr. Lee Phillips, UNC - Pembroke

The goal of Carolina Bays: a Paleoclimatic Perspective is to better establish the timing of primary bay formation and subsequent infilling, with attention to climatic controls and conditions during their development. Carolina Bays are shallow, elliptically shaped, oriented landforms found within the Atlantic Coastal Plain from Georgia to New Jersey. A better understanding of their spatial and temporal relationships will assist in understanding the processes that have affected their formation and the timing of events leading to emplacement and subsequent destruction. In accord with NASA's Earth Science research objective, we seek to improve the understanding of the role of oceans, atmosphere, and ice in the climate system which could lead to improved predictive capability for future climate evolution. Data produced during this research will contribute to the terrestrial record in southeastern North America of recent climate shifts including glacial and interglacial cycles of the last 130,000 years. Such understanding of how geologically rapid changes of Earth's climate can cause major ecosystems shifts, which, in turn, lead to development of primary landforms over a wide area could lead to an improved predictive capability for similar climate changes, as well as an improved interpretation of similar geomorphic features elsewhere on Earth and, possibly, beyond. Toward this end, this project includes the training of undergraduates in methods of scientific inquiry through faculty-mentored research experiences coupled with intense training on understanding climate change. These efforts are designed to advance the goals of NASA's Earth Science mission, specifically knowledge within the broad area of the Earth Science and to stimulate interest in further study and pursuit of careers in Earth Sciences.

Cross-talk between Vacuolar Traffic and Plant Gravitropism PI: Dr. Marcela Rojas-Pierce, NC State University

The plant response to gravitropic stimuli is in part mediated by the endomembrane system, as several protein trafficking mutants also display defects in the gravitropic response. This project seeks to characterize the cross-talk between the plant gravitropic signaling pathway and protein trafficking to the vacuole by a chemical genetic approach. Several chemical inhibitors of gravitropism and/or protein trafficking to the vacuole have been previously identified. Our goal is to characterize the effects of a few these inhibitors at the cellular and physiological levels in order to gain insight into molecular mechanisms that are common to these two pathways. Furthermore, since these small molecules affect the response to gravity, they are potential pharmacological agents for modulating plant growth in conditions of microgravity or to inhibit the gravity signals in earth studies with plants or other organisms.

Validated computational tool for optimizing turbine cooling design with CAD-based geometries PI: Dr. Ahmad K. Sleiti, UNC - Charlotte

The need for advanced turbomachinery and heat transfer concepts, methods and tools is critical to enable NASA to reach its goals in the various Fundamental Aeronautics projects. These goals include significant reductions in aircraft fuel burn, noise, and emissions, as well as an ability to achieve mission requirements for Subsonic Rotary Wing, Subsonic Fixed Wing, Supersonics, and Hypersonics project flight regimes. In the compression system, advanced concepts and technologies are required to enable high stage loading and wider operating range while maintaining or improving aerodynamic efficiency. Such improvements will enable reduced weight and part count, and will enable advanced variable cycle engines for various missions. In the turbine, the very high cycle temperatures demanded by advanced engine cycles place a premium on the cooling technologies required to ensure adequate life of the turbine component. Reduced cooling flow rates and/or increased cycle temperatures enabled by these technologies have a dramatic impact on the engine performance. Research is needed in the turbomachinery and heat transfer area to provide: Tools and methods to optimize the turbine cooling design including film cooling and internal cooling, especially considering the ability to incorporate such tools into the engine design cycle. Currently, turbine cooling designs are developed via empirical information which may be derived from idealized cases not applicable to the actual turbine flow environment. It would benefit the community greatly to have a validated computational tool for optimizing the turbine cooling design. This tool should allow the prediction of turbine wall temperatures with sufficient accuracy and within reasonable time scales to allow optimization of the film and internal cooling geometrical features capable of handling CAD-based geometries.

The proposed research will combine all significant parameters that affect the turbine blades and vanes cooling into sophisticated design and optimization tools based on analytical, computational and experimental reasoning under realistic conditions and geometries. These developed tools are unique by allowing the designers to quickly making a design decision. The resulting internal cooling geometry and flow/heat transfer data from this model will be incorporated into a Flow Solver, for final design phase. The results from this research project can be incorporated into the structural/thermal stress life cycle and then into the final engine design cycle.

Vertically Aligned Carbon Nanotube Arrays for Ultrahigh Mechanical Damping PI: Dr. Yong Zhu, NC State University

A variety of civilian and aeronautic oriented dynamic systems are prone to vibratory motions that can become severe when resonance, chaotic and/or aeromechanical instability occurs. The introduction of damping into these systems could lead to alleviation of aero-elastic flutter, reduction of gust loading, increased fatigue life of structural elements, reduced cabin noise and improved maneuverability. An ideal damper should possess high energy dissipation, low weight, large stiffness and good thermal stability. One excellent candidate material could come from carbon nanotubes (CNTs) that possess large elastic modulus, low density and high thermal stability. The proposed research will explore the damping application of vertically aligned CNT arrays and CNT nanocomposites with focus on fundamental understanding on the energy loss mechanisms and damping characteristics under various loading conditions.