Search Results

The paper presents some aspects concerning the working process of an original cyclic dose governor, used for the in-line fuel injection pumps of the direct injection spark ignition engines. Regarding this mechanism as an automatic regulation system, depending of the crank speed and using the transfer functions which are specific to each element, we have obtained the equations that describe the working process of the governor. In order to integrate the system's characteristic differential equations numerical methods were applied, using the LTITR function (Linear Time Invariant Time Response Kernel), adapted from MathLab's 4.2 library. Thus we have obtained graphical representations of the function that describes the governor's response to the engine's speed variation, for the whole speed range of a spark ignition engine and for the 12 dimensional variants of the governor's constituent parts.

Vegetable oils are an interesting alternative to diesel fuel, as they are a renewable source of energy, have a low sulfur content, are safe to store, do not cause skin ailment. However, using vegetable oils in order to fuel direct injection diesel engines creates problems due to their low heat energy and high viscosity. The purpose of the experiments we made was to determine how the injection equipment behaves when sunflower oils are used and how these oils alter the power indexes of the engine. During the test we used three types of sunflower oil and vegetable oil-diesel oil mixtures; both the injection equipment tests and the engine tests were conducted at 20% load, 40% load and full load. We noticed changes in the injection equipment working parameters (injection pressure, cyclic dose etc.) and in the engine's power indexes (output power and torque, fuel consumption etc.).