Experimental investigation of the effects of various factors on the emission characteristics of low-emission natural gas vehicles

Abstract

The aim of this study was to investigate the effects of various factors on the emission characteristics of dedicated natural gas vehicles (NGVs). A conventional light-duty gasoline engine was modified to run on natural gas (NG) by a gas injection system. Experiments were mainly conducted on the optimization of an oxygen sensor, a catalytic converter, and an electronic control unit (ECU) control strategy affecting the emission characteristics of NGVs. Also presented are the emission results of the NGV as a low-emission vehicle by evaluating non-methane organic gases (NMOG). The experimental results present the optimization of the fuel control and exhaust system in NGV that is needed to meet the more stringent emission regulations. It is also suggested that non-methane hydrocarbons (NMHC) constitute about 95 per cent of NMOG, and light-end HCs (C2-C5) account for 91 per cent of total NMOG emissions.

Keywords

natural gas vehicle emission characteristics non-methane organic gases ultralow-emission vehicle

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