Energy used for lighting is one of the major components of total energy consumption in buildings. Nowadays, buildings have a great potential to reduce their energy consumption, but to achieve this purpose additional efforts are indispensable. In this study, the need for energy savings evaluation before the implementation of lighting control algorithms for a specified building is highlighted. Therefore, experimental tests have been carried out in a university building with laboratories and other rooms, equipped with KNX building automation system. A dimmable control strategy has been investigated, dependent on daylight illuminance. Moreover, a relationship between external and internal daylight illuminance levels has been evaluated as well. Based on the experimental results, the authors proposed a method for the rough estimation of electrical energy savings. Since, according to the EN 15232 standard, Building Automation and Control Systems (BACS) play an important role in buildings’ energy efficiency improvements, the BACS efficiency factors from this standard have been used to verify the experimental results presented in the paper. The potential to reduce energy consumption from lighting in non-residential buildings by 28% for offices and 24% for educational buildings has been confirmed, but its dependence on specific building parameters has been discussed as well.

Evaluated atomic data concerning the 4sand 4pconfigurations of Ar I are averaged in order to simplify their use in various cases of Ar plasma modeling and diagnostics. These data are used here to model a low-power arcjet, running with Argon at low pressure. In so doing, they are explicitly introduced in the chemical processes included in a fluid Navier-Stokes type code, allowing for evaluation of the spectroscopically measurable level populations and of the electronic temperatures. The characteristics of the model are described and the main processes are discussed in view of the results of the calculations.

The modelling of a dc plasma source operating at low power and at low mass flow rate is presented. The physical description of the electric arc in volume with chemical and thermal non-equilibrium conditions is given: two-temperature model, ionization-neutralization process and arc-gas interactions are discussed. The modelling assumptions are justified by the local non-dimensional numbers characterizing the system (Damkhöler, Reynolds and Knudsen numbers). Special attention is focused on the influence of the arc power on the thermal non-equilibrium between electrons and heavy particles and the resulting ionization rate. The kinetic thermal non-equilibrium is shown as a decreasing function of the arc discharge current and it is established that the electron density never reaches equilibrium conditions, even at the throat exit. Calculations have been performed for a stationary arc confined to the throat. The gas is argon and the flow is axisymmetric and stationary.

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This contribution proposes a description of selected experimental activities conducted in aerospace sciences and dedicated to generate experimental data to assess atmospheric entry plasma models. In order to provide comprehensive set of experimental data, high enthalpy shock tube facilities have been developed to generate plasma representative of entry plasma for broad range of trajectory entry conditions. The shock-heated plasma is obtained through adiabatic compression and the resulting post-shock plasma flow exhibits thermodynamic state analogous to actual entry plasma. However, significant insight can be obtained through experiments conducted also with non-equilibrium plasma flows obtained with other methods. The typical methodologies adopted to provide experimental data of interest to enhance entry plasma modeling are sketched for four distinct non-equilibrium plasma kinds produced respectively by four specific ground facilities. The contribution firstly will consider experimental campaigns conducted with a high enthalpy shock tube in order to document in absolute radiance the radiative signature in the UV spectral range of an Earth entry plasma. Then, the investigations of the interaction between a shock wave and an electrical discharge will be described. These investigations were performed to identify the role of the internal degrees of freedom of molecular gases on the propagation of the shock. Also, the contribution covers investigations devoted to the thermodynamic state characterizations by means of spectroscopic diagnostics in the cases of the non-equilibrium plasmas flows generated by plasma wind tunnels. The examination of the Saha-Boltzmann equilibrium is proposed in the case of a subsonic plasma flow. And at last, the characterization methods of air supersonic plasma jet are presented and the 2D distributions of the subsequently measured plasma properties are documented for a straight comparisons with non-equilibrium plasma jet computations.