Detection conditions of the motor vehicle emissions law
Source:China's environmental Author: Date:6,10,2012

Countries in the world control the limits of the motor vehicle emissions standards in accordance with national conditions, and detect the status of the vehicle emission test methods are basically the load conditions of law and without load at idle speed (or the free acceleration smoke method) .

Conditions set the maximum gross mass of vehicles over 3500 kilograms) for light vehicles (refer to plant the vehicle is placed in the drum test rigs simulate real driving vehicles on the road speed and load, in accordance with certain conditions (such as idle, acceleration, constant speed, deceleration and other conditions) operation. By serial dilution sampling equipment will be a certain percentage of diluted exhaust sample gas into the analysis system, measuring the concentration of various pollutants diluted test vehicle emissions during the entire experiment (such as CO, HC and NOx,). Then, according to the measured pollutant concentration in the exhaust flow and other parameters to calculate the total amount of the test vehicle in the entire operation, emissions of each pollutant (unit: g / km).

Conditions of heavy-duty vehicles (refer to the factory set of vehicles with a maximum total mass greater than 3500 kg) is the engine on the engine dynamometer test stand, operating according to a certain speed load conditions. Meanwhile, the use of sampling equipment will be a certain percentage of the exhaust sample gas directly into the analysis system for measuring the concentration of the engine in the emissions of various pollutants of various test conditions (eg, of CO, HC and NOx). Then, based on measured concentrations of pollutants, the exhaust flow, load and other parameters to calculate the total amount of each pollutant emitted by the engine during the entire experiment (unit: g / kWh).

Conditions method is the simulation of vehicles on the road operating conditions, the simultaneous measurement of the pollutant emissions, the emissions measured results basically reflect the actual emissions of the vehicle position, therefore, be recognized as the evaluation of car (or engine) emissions from the status of the most scientific test, but also to judge a variety of automotive emission control devices purification effect of the most convincing test methods. At present, countries in the world using a loaded mode testing new stereotypes vehicle (or engine) and the new production vehicles (or engine) emissions status, and to develop appropriate limits. Meanwhile, the working conditions of the purifying effect of a variety of automotive emission control devices to be assessed.