At the end of the XX century, an increasing number of cars were equipped with diesel engines, which are more economical than gasoline. But not so long ago it became clear that despite the existence of exhaust gas neutralization systems in diesel engines, harmful emissions are many times higher than the permissible norms and declared numbers. In this regard, a number of countries are banning the use of diesel cars in large cities.
The environmental performance of diesel engines can be significantly improved by replacing liquid motor fuel with alternative gas, primarily natural gas (methane).
The Department of Theoretical and Industrial Heat Engineering under the leadership of prof. G.B. Varlamov, together with the production and commercial company "AvtoGazGlobal" (General Director M.I. Yakovenko) are developing and implementing gas-diesel power supply systems designed for the conversion of diesels of trucks and tractors in gas-diesel in the conditions of motor transport enterprises.
Gas diesel is a two-fuel engine, the cylinders of which are supplied with a gas-air mixture, which is ignited by a small, so-called "ignition dose" of diesel fuel, which is injected through the standard diesel injectors. The advantages of gas diesels are their versatility, the ability to work on both gas-diesel and diesel cycle; reduction of operating costs by 60… 70% due to the replacement of diesel fuel with cheaper gas; high efficiency; 2-3 times reduction in the opacity of exhaust gases; the relative ease of conversion of diesels in gas diesel engines in operation.
One of the latest developments is a universal power system with microprocessor control for the conversion of mass-produced automobile and stationary diesels into gas diesel.
The transition to a gas-diesel work flow with the proposed system does not require design or technological changes to the basic diesel model. The engine becomes universal and retains the ability to fully operate on gas-diesel and diesel cycles. Such conversion can be carried out both at motor plants for the manufacture of diesels, and in operating conditions. To do this, additional equipment is installed, which includes the developed universal microprocessor power supply system for the gas diesel engine.
The usage of such a system of power supply and regulation of the internal combustion engine (ICE) significantly improves the energy and environmental performance of the ICE and brings them into line with modern international requirements. The versatility of the basic scheme of the system lies in the possibility of its easy adaptation (by adjusting the program of the microcontroller) for efficient operation as part of a particular diesel engine. The use of an electronic microprocessor unit allows for the implementation of flexible distribution and phase (coinciding with the intake period) gas injection through the engine cylinders; provides automatic speed control during the diesel-diesel cycle and the necessary correction of the ignition dose of diesel fuel depending on the speed, load and thermal state of the engine. This hybrid power supply system saves up to 75… 80% of diesel fuel by gas replacement. The annual economic effect of its implementation, for example, only on one dump truck BelAZ-75405 (30 tons) is 250… 350 thousand UAH, and the payback period does not exceed 6 months.
With the support of the sponsor - LLC "Logistics Company Obolon" and directly the head of the autohousehold O.V. Petrov, who kindly provided and prepared a truck GAZ-3309 to test the developed system (see photo), a study of the car on the stand of traction properties of cars (mod. 4819 BM) with a prototype of a gas-diesel power supply system in the profile institute of the Ministry of Infrastructure of Ukraine - SE "DerzhavtotransNDIproekt". The obtained results fully confirmed the preliminary calculations of environmental and energy performance of the diesel engine during the transition to gas-diesel mode.
The conclusion of technical examination and the permission for application of the developed gas-diesel power supply system on vehicles in Ukraine is received.