Emission performance assessment of passenger car engines: A comparative analysis

The automotive market is constantly developing and employing innovative technologies. The new trend of electromobility affects the whole world and is part of the transformation of the economy. Also, the European Union takes significant steps to support the development of the electric sector of the automotive market. This is confirmed by the signed declaration in Glasgow, which leads towards a ban on the sale of cars with combustion engines by 2035. Due to the initiatives taken by international institutions to green all processes in the economy and the defined legal framework, these activities have an influence on other market participants. The problem identified in this article is the actual impact of implemented solutions concerning the type of engine used in cars offered for sale in Poland. The aim of the article is accompanied by a research question, is the electric vehicle less harmful to the environment? The paper compares cars of the same producer, class and type with petrol, diesel, hybrid (petrol-electric) and electric engines in terms of the environmental impact parameters described in the methodology. The research method is a comparative analysis of SUVs of urban type. As a result of the research, it has been determined that a vehicle with an electric engine emits the least amount of carbon dioxide and is the most environmentally friendly solution.

Alternative propulsion plants for modern LNG carriers

This paper shows the latest evolution trends of propulsion plants of modern LNG tankers. Features of conventional and advanced steam plants were confronted with propulsion plants such as Dual Fuel - Diesel electric and plants equipped with slow speed two stroke diesel engines. Propulsion plants were compared in terms of plant efficiency, reliability and environmental. The shipyard’s order book and the active fleet of LNG carriers with a capacity above 65000 m3 were analyzed

Identification of waste heat energy sources of a conventional steam propulsion plant of an LNG carrier

This paper presents the origins of marine steam turbine application on liquefied natural gas carriers. An analysis of alternative propulsion plant trends has been made. The more efficient ones with marine diesel engines gradually began to replace the less efficient plants. However, because of many advantages of the steam turbine, further development research is in progress in order to achieve comparable thermal efficiency. Research has been carried out in order to achieve higher thermal efficiency throughout increasing operational parameters of superheated steam before the turbine unit; improving its efficiency to bring it nearer to the ideal Carnot cycle by applying a reheating system of steam and multi stage regenerative boiler feed water heating. Furthermore, heat losses of the system are reduced by: improving the design of turbine blades, application of turbine casing and bearing cooling, as well as reduction in steam flow resistance in pipe work and maneuvering valves. The article identifies waste energy sources using the energy balance of a steam turbine propulsion plant applied on the liquefied natural gas carrier which was made out basing on results of a passive operation experiment, using the measured and calculated values from behavioral equations for the zero-dimensional model. Thermodynamic functions of state of waste heat fluxes have been identified in terms of their capability to be converted into usable energy fluxes. Thus, new ways of increasing the efficiency of energy conversion of a steam turbine propulsion plant have been addressed

Determination of the operating parameters of steam jet injectors for a main boiler’s regenerative feedwater system

Due to the development of alternative propulsion systems, there is a need for LNG tanker turbine propulsion plants to regain their competitiveness. Previous research revealed effective methods to increase the thermal efficiency of the steam cycle based on quality assessment, and it was proposed that the latent heat of the main turbine exhaust steam could be recovered. Research was carried out for the steam cycle using regenerative heat exchangers fed by steam jet injectors. In this paper, an algorithm to determine the operating parameters of steam jet injectors, and the calculation results for different drive steam parameters are presented. The obtained results will be used as input parameters for further heat balance calculations of the proposed regenerative steam cycles

Application of a Two-Stage Steam Jet Injector Unit for Latent Heat Recovery of a Marine Steam Turbine Propulsion Plant

The paper presents the results of the numerical research of the steam jet injector applications for the regenerative feed water heating systems of marine steam turbine propulsion plants. The analysis shows that the use of a single injector for a single heat exchanger results in a relative increase in the thermal efficiency of the plant by 0.6–0.9%. The analysis also indicates the legitimacy of the usage of multistage feed water heating systems, which would enable the operating parameters optimization of the injectors. The obtained steam pressure up to the value of 1.8 barA allows for the heating of the feed water up to 110 °C. For higher degrees of feed water heating in the heat exchangers, it is necessary to supply heating steam of higher pressure. Therefore, the usage of two-stage steam jet injector units was considered advisable for the analyses

Experimental Investigation of Concrete Sandwich Walls with Glass-Fiber-Composite Connectors Exposed to Fire and Mechanical Loading

Precast concrete sandwich panels (PCSPs) are known for their good thermal, acoustic and structural properties. Severe environmental demands can be met by PCSPs due to their use of highly thermally insulating materials and non-metallic connectors. One of the main issues limiting the wider use of sandwich walls in construction is their unknown fire resistance. Furthermore, the actual behaviour of connectors and insulation in fire in terms of their mechanical performance and their impact on fire spread and the fire resistance of walls is not fully understood. This paper presents an experimental investigation on the structural and thermal behaviour of PCSPs with mineral-wool insulation and glass-fiber-reinforced polymeric bar connectors coupling two concrete wythes. Three full-size walls were tested following the REI certification test procedure for fire walls under fire and vertical eccentric and post-fire mechanical impact load. The three test configurations were adopted for the assessment of the connectors’ fire behaviour and its impact on the general fire resistance of the walls. All the specimens met the REI 120-M criteria. The connectors did not contribute to the fire’s spread and the integrity of the walls was maintained throughout the testing time. This was also confirmed in the most unfavourable test configuration, in which some of the connectors in the inner area of the wall were significantly damaged, and yet the structural connection of the concrete wythes was maintained. The walls experienced heavy heat-induced thermal bowing. The significant contribution of connectors to the stiffness of the wall during fire was observed and discussed

Experimental Investigation of Concrete Sandwich Walls with Glass-Fiber-Composite Connectors Exposed to Fire and Mechanical Loading

Precast concrete sandwich panels (PCSPs) are known for their good thermal, acoustic and structural properties. Severe environmental demands can be met by PCSPs due to their use of highly thermally insulating materials and non-metallic connectors. One of the main issues limiting the wider use of sandwich walls in construction is their unknown fire resistance. Furthermore, the actual behaviour of connectors and insulation in fire in terms of their mechanical performance and their impact on fire spread and the fire resistance of walls is not fully understood. This paper presents an experimental investigation on the structural and thermal behaviour of PCSPs with mineral-wool insulation and glass-fiber-reinforced polymeric bar connectors coupling two concrete wythes. Three full-size walls were tested following the REI certification test procedure for fire walls under fire and vertical eccentric and post-fire mechanical impact load. The three test configurations were adopted for the assessment of the connectors’ fire behaviour and its impact on the general fire resistance of the walls. All the specimens met the REI 120-M criteria. The connectors did not contribute to the fire’s spread and the integrity of the walls was maintained throughout the testing time. This was also confirmed in the most unfavourable test configuration, in which some of the connectors in the inner area of the wall were significantly damaged, and yet the structural connection of the concrete wythes was maintained. The walls experienced heavy heat-induced thermal bowing. The significant contribution of connectors to the stiffness of the wall during fire was observed and discussed

Influence of Different Fiber Dosages on the Behaviour of Façade Anchors in High-Performance Concrete

The behaviour of façade anchors in high performance fiber reinforced concrete (HPFRC) has not been investigated in sufficient detail in recent years. The regulations in the European Technical Approvals also do not fully describe the load-bearing capacity of anchor systems. Due to the increase in the production of HPFRC elements, it is necessary to analyse the impact of added fibers in the concrete composition on the behaviour of anchors. In particular, the behaviour of anchors in filigree façade elements, which is one of the main application areas of the programme of polypropylene (PP) fiber-reinforced concrete, is therefore analysed. With a sufficient content of PP fibers surrounding the steel anchors oriented in an optimal direction, the fibers may enhance both the load-bearing capacity of anchors and the ductility of concrete. However, unfavourable effects on the installation process or even on the load-bearing capacity may also occur due to unfavourable fiber orientation. Therefore, tensile and punching tests were carried out in uncracked concrete with different types of anchor systems containing a tension anchor and an adjustable spacer bolt. The PP fiber content of the concrete component varied during the tests

Mechanical and Thermal Properties of Basalt Fibre Reinforced Polymer Lamellas for Renovation of Concrete Structures

The level of energy consumption in renovation activities of buildings has huge advantages over the demolition of old buildings and the construction of new structures. Such renovation activities are usually associated with the simultaneous strengthening of their elements, such as externally bonded carbon fibre reinforced polymer (CFRP) lamellas or sheets on vertical and horizontal surfaces as structural reinforcements. This means the process of refurbishing a building, as well as the raw materials themselves have a significant impact on CO2 emissions and energy consumption. This research paper demonstrates possibilities of replacing state of the art, highly energy-intensive CFRP lamellas with basalt fibre reinforced plastics as energy-efficient structural reinforcements for building constructions. The mechanical and thermal properties of basalt fibre reinforced polymer (BFRP) composites with variable matrix formulations are investigated. The article considers macroand microstructures of innovative BFRP. The investigations focus on fibre–matrix interactions with different sizing formulations and their effect on the tensile strength, strain as well as modulus of elasticity

Mechanical and Thermal Properties of Basalt Fibre Reinforced Polymer Lamellas for Renovation of Concrete Structures

The level of energy consumption in renovation activities of buildings has huge advantages over the demolition of old buildings and the construction of new structures. Such renovation activities are usually associated with the simultaneous strengthening of their elements, such as externally bonded carbon fibre reinforced polymer (CFRP) lamellas or sheets on vertical and horizontal surfaces as structural reinforcements. This means the process of refurbishing a building, as well as the raw materials themselves have a significant impact on CO2 emissions and energy consumption. This research paper demonstrates possibilities of replacing state of the art, highly energy-intensive CFRP lamellas with basalt fibre reinforced plastics as energy-efficient structural reinforcements for building constructions. The mechanical and thermal properties of basalt fibre reinforced polymer (BFRP) composites with variable matrix formulations are investigated. The article considers macro- and microstructures of innovative BFRP. The investigations focus on fibre–matrix interactions with different sizing formulations and their effect on the tensile strength, strain as well as modulus of elasticity