Zbigniew Kneba

The thermal balance of vehicle cabins when only an internal combustion engine was used was an insignificant element of the vehicle design. The excess thermal energy on board did not require energy saving. Only the cold start was slightly problematic. However, it could still use a combustion heater that quickly warmed up the cabin. In purely electric cars, each use of electricity stored in the battery shortens the vehicle's range. Three types of heating are used in this case: a) an electric air heater; b) an electric heater for the liquid cooling the drive components; c) a heat pump receiving heat from the drive components, also temporarily supported by an electric air or liquid heater. The use of a heat pump is the most promising and is also used in cheap city cars (e.g. Renault ZOE). The source of thermal energy for a heat pump is: a) vehicle drive engine(s); b) AC/DC converters – charger, DC/DC – charger, DC/AC – motor inverter; c) battery. In cheaper vehicles, air cooling is partially used; currently, a mixture of antifreeze fluids is used. The article presents a calculation example for a city bus cabin.

In the presented research, the authors dealt with the specific properties of the combustion process of dimethyl ether (DME) in a combustion car (Volkswagen Golf IV) engine AJM 1.9 TDI PDE made by Volkswagen factory. Dimethyl ether is an alternative fuel produced most often from natural gas, which...

The use of alternative fuels and, in the future, synthetic fuels has forced changes in the design of fuel supply systems in internal combustion engines. When operating a stationary engine at constant load, the possibility of using lean fuel mixtures appears. Selection of a precisely operating mixture ignition system requires changes in traditional fuel systems. The article presents the current designs of fuel supply systems and their properties. Attention was paid to operating parameters resulting in acceptable emissions of toxic exhaust gas components. Control systems that make the operation of the fuel system dependent on the properties of fuels are being developed.

The aim of the present research was to develop a mathematical model for estimating the amount of viscous gas generated as a function of weather conditions. Due to the lack of models for predicting gas formation caused by sudden changes in weather conditions in the literature, such a model was developed in this study using the parameters of landfills recorded for over a year. The effect of temperature on landfill gas production has proved to be of particular interest. We constructed an algorithm for calculating the amount of the produced gas. The model developed in this study could improve the power control of the landfill power plant.

The worldwide aim of reducing environmental impact from internal combustion engines bring more and more stringent emission regulations. In 2017 by EU has been adopted new harmonized test procedure called WLTP. In general terms this test was designed for determining the levels of harmful emissions and fuel consumption of traditional and hybrid cars. This procedure contains specific driving scenarios which representing real-life driving patterns. Test cycles contain vehicle velocity versus time profiles and directly in powertrain analysis on the test benches cannot be used. In order to back calculate drive cycles to engine rpm versus torque profiles a simple longitudinal vehicle dynamics method was used in this paper. Moreover, in order to determine most representative engine operation points duing WLTP a density based grid clustering method was implemented. The experimental part of the study focuses on the comparative evaluation of the effect of various diesel to LPG substitution ratios (0% LPG, 10% LPG, 20% LPG and 30% LPG) on combustion and emission characteristics of dual-fuel diesel engine.

The dual fuel (DF) combustion mode is proven solution that allows to improve or get at the same level engine performance and reduce toxic compounds in exhaust gases which is confirmed by researchers and end-users. DF combustion mode uses two fuels gaseous fuel as a primary energy source and a pilot quantity of diesel fuel as ignition source. However, in order, to fully take advantage of the potential of the dual fuel mode, DF system must be proper calibrated. Despite the existence of commercial control systems for dual fuel engines on the market, the literature on the important parameters for the engine's operation introduced during calibration is scarce. This article briefly describes a concept of working algorithm and calibration strategy of a dual fuel electronic control unit (ECU) The purpose of calibration is to achieve the greatest possible use of an alternative gaseous fuel without causing accelerated engine wear.

The ecological issues and the depletion of crude oil, has led the researchers to seeking for non-petroleum based alternative fuels, along with more advanced combustion technologies, and after-treatment systems. The use of clean alternative fuels is the one of the most perspective method that aiming at resolving of the said issues. One of the promising alternative fuels that can be used as a clean high efficiency compression ignition fuel with reduced of toxic emissions is dimethyl ether (DME). Moreover, it can be produced from various feedstocks such as natural gas, coal, biomass and others. This article describes the properties and the potential of DME application on the combustion and emission reduction characteristics of the compression ignition engines.