Research On The Influence Of Environmental Testing Factors With Passenger Vehicle Emission Results And Engineering Target Setting

With the increasing possession of motor vehicles,the automobile industry plays an indispensable key role in the development of the real economy of China and even the world.However,with the popularization of private cars,global warming is becoming more and more serious,and environmental deterioration is particularly prominent.Since the implementation of the Ⅴ emission regulations,the interpretation of emission standards has been gradually deepened.Through years of comparative study,the Ⅵ emission standard with unique adaptability of China has gradually formed.Compared with Europe developed countries where the automobile industry started earlier,China started the emission test of passenger vehicles relatively late,test environment factors including environment temperature,soaking time,battery voltage and driver’s habit.These variables(factors)in the regulations standard also exists certain change interval,in the change interval,the different factors on the testing result has a certain degree of influence,and these factors directly affect the vehicle emission limit value of the project objectives.The determination of engineering target value is closely related to the enterprise’s technical level and product quality standard.If the target value of the emission project is high,and the emission value of the vehicle has exceeded the emission standard limit when it does not run to 160,000 kilometers.The low target value of emission project makes it difficult to achieve the target,extends the development cycle and increases the development cost,or delay the launch date,etc.,which affects the enterprise’s efficiency,product consistency,too many spot checks,and increases vehicle cost,personnel and equipment investment.In order to solve the above problems existing in the enterprise product development process,combined with the engineering practice of several related aspects of the strong emission performance test,the test influencing factors of uncertainty and consistency of product specific research,on the premise of fully grasp all the outside factors,targeted research,determine the project goal setting method and accurately determine product qualified through sexual risk assessment.Main research contents as follows: 1)test environment factors: respectively on test environment temperature,battery voltage,leaching time driver factors and laboratory research,within the scope of the regulations allow deviation,through theoretical analysis and test validation,grasp the factors significantly influence on THC,NOX,CO emissions,get the results of normal distribution curve.2)influence of product consistency: after accurately grasping the influence of various uncertainties and environmental factors on the results,and the method of the deviation between the actual emission level of some pollutants standard,the consistency of product emission level of cold start at normal temperature was evaluated by of the sample vehicle.3)determination of the target value of new product development engineering: combining the above research,the determination method of the target value of new vehicle engineering is developed.The emission consistency of existing vehicle models and the degradation coefficient of their emission durability data,which are used for reference to develop more reasonable engineering targets for new vehicle models.Through theoretical research and actual vehicle inspection,a certain number of vehicles(P)are finally obtained the method which meet the engineering target of emission regulation.The determination methods are summarized as follows:Through theoretical research and actual vehicle inspection,a certain number of vehicles(P)are finally obtained the method which meet the engineering target of emission regulation.The determination methods are summarized as follows:1.Determine the standard deviation of a certain pollutant discharge result;2.Determine the ratio of standard deviation to P according to the given probability;3.It is the engineering goal to meet the probability of passing.Where,?is the standard deviation of the sample standard deviation against the population;A is the limit value of the number of cars passing P;? is numerical characteristic sample;L is the emission standard limit(after cracking).With emission consistency data of different vehicle models can not only determine reasonable emission engineering targets for new vehicle models under given probability conditions,but also give a reasonable assessment on the probability of emission compliance of the established emission engineering targets.The more the emission consistency data of different vehicle models are accumulated.In conclusion,the method of setting emission engineering targets is obtained.