Evaporation generation in the vehicle fuel tank. Canister feed strategy optimization

Abstract

Introduction (problem statement and relevance). In addition to the toxic substances generated during fuel combustion in the engine, the vehicle generates a significant amount of hydrocarbons in the form of fuel vapors generated as a result of evaporation from the fuel tank and fuel system components. The evaporation process parameters and the amount of fuel evaporations are determined by dynamics of fuel heating in the tank in various vehicle operation modes. Modern requirements for the limit level of emissions caused by evaporation become much stricter. Therefore, the solution of the task of fuel evaporation minimization and prevention of ingress thereof into the atmosphere is relevant and practically significant. The purposes of the studies are to develop a model of the processes of evaporation generation in the vehicle fuel tank based on the analysis of mathematical modeling and experimental research results as well as to develop the optimum strategy and algorithm of the canister feed.Methodology and research methods. In the study, a combination of analytical methods of the classical thermodynamics with modeling in the Simcenter Amesim integrated program platform environment is used.Scientific novelty and results. It has been found that transition from feeding the canister with an open vapor space to evaporation in a fixed-volume space allows significant reduction of the amount of hydrocarbons delivered to the canister.Practical significance. It has been found and proved that accumulation of hydrocarbons in a closed tank with discrete cyclic feed of the canister allows significant reduction of evaporation generation and lowering of the requirements for the canister parameters. An algorithm of optimum canister feed is suggested.