Laura Dern’s Vomit, or, Kant and Derrida in Oz

This article explores the role of disgust in Kant’s aesthetic philosophy, Derrida’s deconstruction of Kant’s third Critique in his article 'Economimesis,' and the figure of vomit in two films by David Lynch in order to argue for the ethical possibilities of not giving ground relative to one’s disgust—what I term an ethics of the worse than the worst

Artificial saliva aerosol source and detection system for spreading analysis in indoor environments

In the context of the Corona pandemic the investigation of aerosol spreading is utmost important as the virus is transported by the aerosol particles exhaled by an infected person. Thus, a new aerosol generation and detection system is set up and validated. The system consists of an aerosol source generating a particle size distribution mimicking typical human exhalation with particles sizes between 0.3-2.5 µm and an array of Sensirion SPS30 particulate matter sensors. An accuracy assessment of the SPS30 sensors is conducted using a TSI OPS3330, a high-precision optical particle sizer. Low deviations of ±5 % of the particle concentration measured with the SPS30 with respect to the OPS are reported for concentrations below 2’500/cm³ and +10% for particle densities up to 25’000/cm³. As an application example the system is employed in a short distance single-aisle research aircraft Dornier 728 (Do728) located at DLR Göttingen, to investigate the large-scale aerosol-spreading. With this measurement system a determined spreading distance from an index passenger extending one seat row to the front and two seat rows to the back is determined

Development of secondary vortex structures in rotor wakes

The blade tip vortex system is a crucial feature in the wake of helicopter rotors, and its correct prediction represents a major challenge in the numerical simulation of rotor flows. A common phenomenon in modern high-fidelity CFD simulations is the breakdown of the primary vortex system in hover due to secondary vortex braids. Since they are strongly influenced by the numerical settings, the degree to which these secondary vortex structures actually physically occur is still discussed and needs experimental validation. In the current work, the development of secondary vortex structures in the wake of a two-bladed rotor in hover conditions was investigated by combining stereoscopic particle image velocimetry measurements in different measurement planes and high-fidelity simulations. Secondary vortex structures were detected and quantified at different axial locations in the wake by applying an identical scheme to the measured and simulated velocity data. In agreement, it was found that the number of secondary vortices is maximum at a distance of 0.8R below the rotor. The more intense secondary vortex structures were quantitatively well captured in the simulation, whereas in the experiment a larger number of weaker vortices were detected. No distinct preferential direction of rotation was found for the secondary vortices, but they tended to develop in vortex pairs with alternating sense of rotation. A clustered occurrence of secondary vortices was observed close to the primary tip vortices, where the rolled-up blade shear layer breaks down into coherent vortex structures

Reference experiment on aerosol particle transport for dynamic situations

To study airborne transport of aerosol particles by mixed convection and dynamic situations within a closed room, the Cottbus Aerosol Particle Reference Experiment (CARE) was built and equipped, which includes thermal manikins and a spreader dummy. For various flow configurations (location of spreader, heating bodies, windows opened, air ventilation with and without air purification systems) flow visualisation was performed, particulate matter sensors (PMS) measured local particle concentrations, head-mounted camera systems counted particle concentrations of individuals and finally, large field of view Shake-The-Box Particle Tracking delivered velocity fields. The comprehensive experimental configuration of different measurement systems are discussed in terms of their aerosol transport properties and quantitative results, effective application and comparative efficiency explaining the flow dynamics. The findings from these experiments also provide information under which circumstances particularly high concentrations of aerosol particles can be found on which locations