In this work, we build the model and derive the theory of nonlinear deformation for substitutional alloy AB with interstitial atom C and face‐centered cubic structure under pressure from the statistical moment method. The calculation results for FCC‐AuCuSi are presented. We obtain the values of density of deformation energy, maximum real stress, limit of elastic deformation, and the stress‐strain curve and compare the calculated results with experiments and other calculations.

This study analyzes the feasibility of increasing the energy and economic efficiency of a residential heating and domestic hot water (DHW) preparation system with a solar-assisted air-to-water heat pump (AWHP), implemented in southeast Romania. The following options are evaluated from the sustainability point of view (energy, economic and CO₂ emissions): renovation of the building and modernization of the system by integrating an electric accumulator, increasing the capacity of photovoltaic panels (PV) and solar thermal collectors (STCs), and the option of replacing the AWHP with a ground-source heat pump (GSHP) with a vertical loop (GSHP-VL) and a GSHP with a horizontal loop (GSHP-HL). The energy performance of heating systems was simulated using GeoT*SOL software. The results show that by renovating a home, the energy requirement for heating decreased by about 58%; therefore, following the current financial rules applied to prosumers, the GSHP-VL system has the best energy performance (electricity consumption and solar coverage rate of this consumption), economic performance (investment recovery period and annual operating cost) and environmental performance (lowest CO₂ emissions) and that through a government program that promotes energy efficiency and the use of renewable energy sources in homes, capital costs can be reduced by (43–57)% in the case of systems with HP, PV and electric storage. This study shows that a 5 kW PV system combined with 5 kWh battery cannot cover the full heat demand of a medium-to-large house during the winter, and for full energy independence, a larger PV array paired with a higher-capacity battery is necessary. Generous government subsidies amounting to 50% can reduce the payback period for such investments from (11.26–14.68) years to (5.86–7.26) years.

The paper presents a study concerning the influence of air conditioning system operation on the increase of gases emissions from cars. The study focuses on urban operating regimes of the automobile, regimes when the engines have low loads or are operating at idling. Are presented graphically the variations of pollution emissions (CO, CO₂, HC) depending of engine speed and the load on air conditioning system. Additionally are presented, injection duration, throttle position, the mechanical power required by the compressor of air conditioning system and the refrigerant pressure variation on the discharge path, according to the stage of charging of the air conditioning system.

The paper presents a study of smoke emissions for car Dacia Solenza 1.9D-SDI (63HP) which was produced by Renault in Romania. A similar engine can also be found on the Kangoo Express and Kangoo Passenger cars respectively. Smoke emissions are analyzed comparatively, between idling regimes and load regimes. Also are presented variations of engine speed, accelerator pedal position, fuel flow injected, automotive speed, which are taken using OBD II connection and Autocom CARS CDP+ Scanner. To simulate the load regimes chassis dynamometer V-Tech Dyno VT-2/B1 was used. A module for measuring the opacity of the exhaust gases was used, which is in the gas analyzer Ultimax 600. In graphics are shown variations of the opacity of exhaust gases between idling regimes and load regimes considered. The different pollutions levels with smoke are analyzed between idling regimes and low loads, respectively high loads. Conclusions about the level of pollution are stated. Also are make recommendations for operating regimes of the car, so as to reduce the level of pollution.

The paper presents a study of NO_x and CO₂ emissions for a standard diesel direct injection engine, which equips the Renault-Dacia Solenza 1.9D-SDI cars. The different pollutions levels are analysed between idling regimes and medium and high loads at different speeds and transmission gearboxes. To simulate the load regimes, chassis dynamometer V-Tech Dyno VT-2/B1 was used. The exhaust gases were taken to various operating modes on the chassis dynamometer, specific regimes in urban and extra-urban mode. In the paper, some recommendations are made on operating regimes that would ensure the functioning of the car at a lower polluting level.

Because the air pollution is a serious environmental problem, this study aims to identify the smoke emissions level of different driving regimes for diesel-powered vehicles that run on roads in urban and extra-urban areas. For the experimental determinations we used a car within the Euro 3 pollution norm, because according to the statistics of the National Institute of Statistics, in 2020 the number of Euro 3 and Euro 4 cars in Romania represents 54% of the total of 7,3 million registered cars and only 1,7 million Euro 5 and Euro 6 are registered. The study has been performed in laboratory conditions and simulates various driving modes. To simulate the load regimes on horizontal roads, chassis dynamometer V-Tech Dyno VT-2/B1 was used, equipment that is in the Thermal Systems and Automotives Department. This work investigates the effects of vehicle speed and fuel consumption on smoke emissions and at the same time makes recommendations concerning the optimal operating regimes of diesel cars to reduce the level of smoke pollution.