Research On Vehicle Exhaust Emission Concentrations&Ventilation System Of City-highway Tunnel

City-highway tunnel is a relatively closed environment,it's difficult for vehicle s's off-gases to exhaust in a short time,this will certainly affect the health of the human body。In order to protect the tunnel's hygiene and peoples's health safety,it has great practical significance to study the tunnel vehicles's exhaust emission concentration limit。This paper focuses on the two large harmful gases 's(CO and NO₂) concentration emission limit of vehicles exhaust,we established CO concentration design limit's CFK equation of city-highway tunnel,for horizontal and vertical ventilation mode of ventilation,different speed and different length of the tunnel,given the corresponding CO concentration design limit。Finally based on the NO₂ 's emission load and dilution NO₂ to a tunnel allow range's required ventilation,proposed city-highway tunnel's concentrations emission limit of NO₂。The results can as a reference for city-highway tunnel's ventilation systems,fire alarm systems and monitoring software design and development。As a result of city-highway tunnel's ventilation system is extremely complex,it has a strong time-varying,nonlinear and hysteresis characteristics,the traditional control method is difficult to establish accurate mathematical model,control effect is not good,not only cost energy,also improved the tunnel's operation cost。Therefore,to find a good intelligent ventilation control system to solve the traditional controll method's existed problems,has become one of the urgent problem to a solve of city-highway tunnel construction。To solve these problems,in this paper,fuzzy control technology has been introducesd and apply it in the tunnel ventilation system。In this paper,we established the tunnel ventilation system's air dynamic model,pollution model,traffic model and control model,and gives the relationship of them。In MATLB,with CO concentration deviation,â…¥concentration deviation,traffic as input values,fan number as output value,established its subordinate function,gives theirs membership functions tables。And set their linguistic variables and basic domain,then convert them to fuzzy control's discrete domain,according to the operator's control experience to design the fuzzy control rules,use Mamdani inference method to reasoning and gravity method to defuzzification,given the fan open amount's fuzzy control table,get the precise number of fan open sets。Finally,we simulationed and analysised the ventilation system,the results showed,compared with the traditional control method,the ventilation system designed by fuzzy control technology,fan open number are also less,CO concentration andâ…¥concentration changed more gentle than under traditional control,and the concentration was lower,basic keep up the maximum allowed nearby,without appear big fluctuations case。So that,based on the fuzzy control technique's ventilation control system control effect is better,fans live is longer,and it has remarkable energy-saving effect。Therefore,fuzzy control ventilation system has strong practical application value,the fuzzy control technology has important practical significance for city-highway tunnel ventilation system and other industrial control systems。...