Comparison of CFD and one-dimensional Bernoulli solutions of the flow in a plate and frame ultrafiltration module in Z configuration AbstractPredictions of flow and pressure distributions in one bank of a plate and frame ultrafiltration module with five channels in parallel operating in a Z configuration were predicted using (1) Bernoulli's equation and a momentum balance in one dimension and (2) a threedimensional field solution (Computational Fluid Dynamics) of the Navier-Stokes equation. CFD solutions were taken as the benchmark and used to refine the 1D model being developed to evaluate flow and pressure distributions for different operating conditions and ultimately different module configurations. The 1D model was able to provide quantitatively accurate flow distribution and qualitatively representative pressure distributions. Flow distributions increased monotonically with increasing channel number, maximum/minimum flow ratios in channels increased from 2 to 6.9 with oil (µ = 0.0361 kg/m/s) as the design cross flow velocity increased from 0.5 to 5 m/s. Pressure distributions were well predicted qualitatively but were typically 40% lower than the CFD solution in the distributor. Key to the accuracy of the 1D model were the implementation of (a) variable contraction co-efficients in the distributor orifice, (b) the 1/7th power law for velocity profiles in the plenums (c) a new approach for combining flows in the collector and (d) assuming only one half of the orifice area was being effectively used by the fluid.

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NASA'S plan to return to the moon by 2020 raises the possibility of conducting science specifically enabled by unique characteristics of the lunar surface. One such science objective is the study of the Epoch of Reionization in the formation of the universe, which has been given top priority by the 2001 National Research Council's Astronomy and Astrophysics Decadal Survey. The "Epoch of Reionization" is the period of transition of the universe from its early state of close-to-perfect uniformity to one of galaxies and inhomogeneous structures, and is currently an area where data is much needed. This period is best studied in the radio waveband, especially at low frequencies, which are inaccessible to ground observatories. In addition, these low frequency waves offer a window on the universe that is unexplored at present. This increases the potential for new and unexpected discoveries. The lunar far side provides an ideal radio-quiet environment essential to observe this period in the universe's history. Such an environment is unavailable on Earth or in near-Earth space. This paper presents the design of a lunar telescope facility that provides the capability to observe the "Epoch of Reionization" by placing a radio array on the far side of the moon. This array is envisioned to consist of 3440 simple radio dipoles, arranged in 215 clusters over an area 62 kilometers in radius, which provides a resolution of 12 arcminutes, to observe the Epoch of Reionization. Highlights of the design include a lightweight, self-deploying structure, a high data-rate wireless communication system, autonomous deployment, and high modularity of system elements. This project is designed to provide value to the exploration community in addition to the science community by leveraging planned lunar exploration architecture transportation elements, including the Ares V launcher, unmanned surface transportation rovers, and communications infrastructure. Additionally, the modularity of the design makes it highly robust from both a technical and a programmatic standpoint.