Distributed diagnostics temperature distribution measurement

By measuring the retention volume of a solute, the distribution coefficient can be obtained. The distribution coefficient, determined over a range of temperatures, is often used to determine the thermodynamic properties of the system this will be discussed later. From a chromatography point of view, thermodynamic studies are also employed as a diagnostic tool to examine the actual nature of the distribution. The use of thermodynamics for this purpose will be a subject of discussion in the next chapter. It follows that the accurate measurement of (VV) can be extremely... 

Chapters 4-6 address specific diagnostic methods in PEFCs. Martin et al. provide a detailed review of methods for distributed diagnostics of species, temperature, and current in PEFCs in Chapter 4. In Chapter 5, Hussey and Jacobson describe the operational principles of neutron radiography for in-situ visualization of liquid water distribution, and also outline issues related to temporal and spatial resolution. Tsushima and Hirai describe both magnetic resonance imaging (MRI) technique for visualization of water in PEFCs and tunable diode laser absorption spectroscopy (TDLAS) for measurement of water vapor concentration in Chapter 6. 

Several studies [23-25] have shown the effect of the combustor inlet conditions on the predicted flame structure, liner temperature, and emissions. These boundary conditions include the axial, tangential, and radial velocities the turbulent kinetic energy and associated length scale. To characterize the flow field at the exit of the TARS, two approaches were adopted. First, advanced diagnostic, such as LDV (discussed above), was used to measure the flow field distribution at the exit of the swirler. The data collected are used for inlet boundary conditions for the LES and database for numerical model validation. Second, a RANS model was used to study mixing and turbulence parameters in the TARS swirler [6]. 

Despite the limited number of molecules that are technically detectable, the above-mentioned scenario is more than enough. Usually, one or two molecular species are observed for local concentration measurements (either spatially resolved through point-like acquisitions or imaged with field techniques). For instance, images of the distribution of hydroxil radical (OH) can be very rich in information. Rather often, this type of data is associated with other diagnostic means capable of complementary data (e.g., temperature or velocity) so that the researchers can reach a comprehensive understanding of the processes they are looking at. 

Additionally, we seek diagnostic tools to understand how the fuel cell performance varies with the location in an individual fuel cell and between fuel cells in a stack. Spatial and cell-to-cell variations in current, temperature, reactant concenhation, and other parameters occur, especially at moderate to high currents and during load transients, and tools are needed which can measure or directly observe these effects. In an operating stack, the number of sensors are Umited due to various cost and size constraints, but laboratory diagnostics are very sophisticated. To understand distributed effects such as flooding in PEFCs or temperature distribution in SOFCs, direct visualization tools and sensors are... 

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