Jet Propellant-8 (JP-8) is used as a fuel for a standard Compression Ignition (CI) engine instead of diesel oil, especially in the military applications. The properties of a kerosene-type fuel, which is JP-8, encourage us to test different strategies of mixture creation and combustion, which could be more effective for this fuel than these elaborated for diesel oil. The experiment aimed to show whether it is possible to realise an effective Low Temperature Combustion (LTC) strategy in a CI engine with a low compression ratio for JP-8 fuel. The tests were focused on the combustion of a lean homogeneous JP-8/air mixture close to the knock limit. Additionally, the combustion process of the homogeneous mixtures diluted with EGR was examined. The AVL research engine with a common rail system and low compression ratio (CR = 12) was adapted for the tests. In order to create a homogeneous mixture early, multi injection of JP-8 under high pressure (90 MPa) was applied. The results of the HCCI operation were compared to the Partially Premixed Combustion (PPC) mode without EGR, tested on the same engine with a low CR. The experiment showed that it is possible to realise the LTC process for the HCCI engine fueled with JP-8, though the knock limited the engine load. The application of EGR allowed controlling the phase and rate of the heat release. The higher share of EGR made the HCCI engine cycles less repetitive. Generally, for the HCCI engine operation, the CO and total hydrocarbons (THC) emissions were on a high level. The PM emission was also relatively high, whereas NO x was maintained on a low level for all of the examined points.

The paper presents some research results to recognize the possibility of realization of the idea of a multi-fuel IC engine. Future construction is planned as a flexible solution for military or special purpose transport means and emergency power generation. The proposed engine would utilize compression ignition mode for combustion of high reactive fuels (JP-8, diesel oil, etc.) or spark ignition mode for gasoline or other low reactive fuels. Practical implementation of the idea requires that highly reactive fuels be burned efficiently at a low compression ratio suitable for both engine modes. For the test diesel oil, JP-8 and its blends with pure rapeseed oil were chosen as easily accessible fuels. The experiment was carried out on naturally aspirated and supercharged AVL research engine with a common rail system and compression ratio CR = 12. The elaborated, unified injection strategy that synchronized the main dose injection timing with the start of the second stage of homogeneous mixture combustion was checked in practice. The proposed injection strategy applied for CI engine with the low compression ratio enabled efficient combustion and comparable, relatively high engine performance for all tested fuels.

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This article is about military equipment research in conditions of reduced atmospheric pressure. Reported cases of equipment damage during work at high altitude or air transport show the need to perform research on phenomena occurring during storage, transport and operation of equipment at a reduced ambient pressure. One of the fragments of the article is devoted to the records contained in normative documents regarding the subject of the study. In addition, an exemplary experiment was made, the purpose of which was to illustrate some of the effects associated with the use of the equipment in the above-mentioned working conditions.

This article aims to present the energy needs of a cargo off-road vehicle, whose primary task is to perform the function of transporting goods. For the assumed character of performed transport tasks, an analytical studies of possible construction solutions were carried out. For further considerations, a classic vehicle with an internal combustion engine and its equivalent powered by electricity produced in the fuel cell stack were adopted. For both of the concerned constructions an energy balance and simulation calculations of traction parameters were made. The result of the executed work is a comparative assessment of the suitability of the fuel cell stack as a primary source of drive energy for a general-purpose cargo off-road vehicle.