A Systematic Methodology for Populating the Aircraft Thermal Management System Architecture Space

Presented at AIAA SCITECH 2021The aircraft thermal management system functions to provide suitable working conditions for pilot, crew, passengers, and the other aircraft systems. The additional weight, drag and power consumption caused by it greatly influences the performance of the aircraft. However, due to rising heat load of emerging novel aircraft concepts, traditional design approaches which rely on data and empirical equations may not apply to the future thermal management systems. Many existing literature which tried to identify the optimal thermal management system architectures only considered limited architecture space where the candidates were pre-selected in terms of experience or intuition. Therefore, viable but non-intuitive architectures may not be included in the design space. To fill this gap, this paper proposes a behavior-based backtracking methodology to systematically populate the architecture space by enumerating both intuitive and non-intuitive architectures. Thermal management requirements for traditional and novel configurations are used to generate the architectures. By comparing the generated architectures with existing ones, this paper validates that the proposed methodology is capable of generating both intuitive and non-intuitive architectures

Steering the nuclear motion in singly ionized argon dimers with mutually detuned laser pulses

We demonstrate that the vibrational nuclear motion of singly ionized argon dimers can be controlled with two ultrashort laser pulses of different wavelengths. In particular, we observe a striking ‘‘gap’’ in the pump-probe-delay-dependent kinetic-energy release spectrum only if the probe-pulse wavelength exceeds the pump-pulse wavelength. This ‘‘frustrated dissociation effect’’ is reproduced by our two-state quantum mechanical model, validating its interpretation as a pump-pulse-initiated population transfer between dipole-coupled Born-Oppenheimer electronic states of the dissociating Ar[subscript 2][superscript +] molecular ion. Our numerical results also reproduce the measured collapse and fractional revival of the oscillating Ar[subscript 2][superscript +] nuclear wave packet, and, for single-pulse dissociation, the decrease of the kinetic-energy release with increasing laser wavelength

Sensitive fluorescence spectroscopy of jet cooled 15NO2.

A spectroscopic setup designed for high resolution spectroscopy of jet cooled molecules is described. The primary features of the new setup are an exceedingly low gas consumption and a high detection efficiency, which are achieved by optimizing the detection geometry of the time gated fluorescence in combination with a special piezo valve. This makes the setup particularly suitable for studying expensive gases that come in small supply. The performance of the setup is demonstrated on the first

The A2B2-X2A1 electronic transition of 15NO2: A rovibronic survey covering 14300-18000 cm-1.

More than 250 rotationally resolved vibrational bands of the

Conical intersection dynamics in NO2 probed by homodyne high-harmonic spectroscopy.

Conical intersections play a crucial role in the chemistry of most polyatomic molecules, ranging from the simplest bimolecular reactions to the photostability of DNA. The real-time study of the associated electronic dynamics poses a major challenge to the latest techniques of ultrafast measurement. We show that high-harmonic spectroscopy reveals oscillations in the electronic character that occur in nitrogen dioxide when a photoexcited wave packet crosses a conical intersection. At longer delays, we observe the onset of statistical dissociation dynamics. The present results demonstrate that high-harmonic spectroscopy could become a powerful tool to highlight electronic dynamics occurring along nonadiabatic chemical reaction pathways

Control of ultrafast molecular photodissociation by laser-field-induced potentials

Depto. de Química FísicaFac. de Ciencias QuímicasTRUEpu