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Understanding the fundamental details of drop/wall interactions is important to improving engine performance. Most of the drop-wall interactions studies are based on the impact of a single drop on the wall. To accurately mimic and model the real engine conditions, it is necessary to characterize spray/wall interactions with different impingement frequencies at a wide range of wall temperatures. In this study, a numerical method, based on Smoothed Particle Hydrodynamics (SPH), is used to simulate consecutive droplet impacts on a heated wall both below and above the Leidenfrost temperature. Impact regimes are identified for various impact conditions by analyzing the time evolution of the post-impingement process of n-heptane drops at different impingement frequencies and wall surface temperatures. For wall temperature below the Leidenfrost temperature, the recoiled film does not leave the surface.

A tire may be one of the most critical and complex components in vehicle dynamics and road loads analyses because it serves as the only interface between the road surface and the vehicle. Extensive research and development activities about vehicle dynamics and tire models have been published in the past decades, but it is still not clear about the applications and parameter identification associated with all of these tire models. In this literature review study, various published tire models used for vehicle dynamics and road loads analyses are compared in terms of their modeling approaches, applications and parameters identification process and methodologies. It is hoped that the summary of this literature review work can help clarify and guide the future research and development direction about tire modeling.

Hollow fiber membranes aerate wastewater without bubble formation by separating the liquid and gases phases with a semi-permeable membrane. These membranes have shown to successfully create aerobic conditions within a biological reactor. This research investigated the effect of long term usage and biofilm growth on membrane's ability to transfer oxygen to solution. Results show that oxygen transfer across the membrane decreased significantly compared to unused membranes in areas of high biofilm growth while low biofilm growth showed only slight decreases.

This research is based on the hypothesis that recycling biofilm can provide the required carbon to increase biological denitrification of the carbon limited early planetary base wastewater. Recycling biofilm may offer significant advantages including a reduction in solid waste from biological wastewater processors, increased N2 return to cabin air, a reduction in TDS loading to the RO system, and increased alkalinity to drive further nitrification. The results of the study indicate that denitrification rate did increase due to the addition of lysed biofilm derived from the nitrification reactor. However, there was a simultaneous large release of additional ammonium. Further work will be required to understand the magnitude of the ammonium release and overall benefits of the process.

The concept that plants and humans in a living system are mutually beneficial was communicated to 2nd - 12th grade students in science educational and outreach programs at Texas Tech University's Center for Space Science. Students traveled to the TTU horticulture greenhouse for a live program, which focused on research in the Engineering Development Unit. The research is funded by NASA's Advanced Life Support. During the program students were presented with the science of growing plants, how plants benefit humans in space, and baseline science vocabulary. A survey instrument was developed to assess student level of understanding of sciences, and their comprehension of living cycles, which work together to support manned space missions. The survey consisted of multiple-choice questions covering topics presented during the program. Likert questions were used to assess student's desire to travel in space, be an astronaut or a scientist, and their enjoyment of science and growing plants.

This research compared the nutrient content of the Biological Water Processor (BWP) effluent at JSC with acceptable nutrient ranges for general hydroponic NFT-solutions. Evaluated nutrient-components were NO3-N, P, K, Ca, Mg, Fe, Mn, Zn, B, Cu and Mo. Compared to Cooper's and Molyneaux's solution (Jones, 1997) BWP-nutrient concentrations were low for Ca, Mg, Fe and B. Compared to the NFT-solution used at KSC (Wheeler et al., 1997), the BWP-effluent showed higher contents of P, K, Zn, Cu and Mo and lower contents of N, Ca, Mg, Fe and B. This indicates that the BWP-effluent could support NFT-plant production.