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ME-5531 Powertrain Lab

Spring 2014

Lab 1

Kirti Deo Mishra, mishra.98

January 14, 2014

In the current work, data from the .dat format files generated by the ETAS INCA softwarewhich is commonly used for the engine calibration and testing is extracted using a MATLAB rou-tine mdfimportand further processed to produce meaningful results.

Following this a short conclusion is drawn based on the results generated .

1. A plot of various variables(averaged over the duration of engine run-time) versus averagethrottle position percentage for corresponding run is presented below.

We can see from the curves above, the nature of experiment conducted for the given dataset.Clearly the throttle is progressively opened from case #1(very low) to case #17(35%) on anaverage. Result of this operation is the induction of more air which is indicated by increasedflow rates of air from one case to next. As intuition suggests, due to various physical (geometryand construction) limitation, the air-flow rate can not keep on increasing forever (unless a

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From the above curve, the following deductions can be drawn. The first case (12kP a) haspre-catalyst equivalence ration around 0.28 which is lean operation of the engine and thusthe power produced is less. As the throttle is opened more and more, the equivalence ratioincreases and reaches the the value 1 (stoichiometric operation). This results in increasedlevels of power generation.

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Appendix Source Code

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

% ME 5531 - Power t r ai n Dynami cs Lab% Week 1% Ki r t i Deo Mi shr a ( # - 98) %% The f ol l owi ng scr i pt pr ocesses t he dat a whi ch i s extr act ed f r om a %% . dat f i l e i nt o meani ngf ul r esul t s%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

cl ccl ear al l ;cl ose al l ;

% Generat i ng Fi l e name i n an aut omated f ashi on

f i l e_pref i x = ' 1000RPM_' ; % t he base name of t he data f i l esf i l e_suf f i x = ' kPa' ; % t he suf f i x of t he dat a f i l esf i l e_ext ensi on = ' . DAT' ; % t he extensi on of t he dat a f i l esf i l e_num = [ 12 19 26 34 41 49 58 . . .

67 74 78 85 89 93 95 97 98 99] ; % t he suf f i x of t he dat a f i l es

mean_dyno_t orque_arr ay = [ ] ; % I ni t i at i ng ' mean' arr aysmean_r pm_ar r ay = [ ] ; mean_MAF_ar r ay = [ ] ; mean_t hr ot t l e_prcnt_arr ay = [ ] ; mean_MAP_ar r ay = [ ] ;

f or a = 1: l engt h( f i l e_num) ,

% Gener ate f i l e name t o i mpor t f n_to_l oad = [ f i l e_pref i x num2st r ( f i l e_num( a) ) f i l e_suf f i x f i l e_ext ensi on] ;

mdf i mpor t ( f n_t o_l oad) ; % l oad dat a f i l e to wor kspace

CASE(a) = a; % St ori ng i n t he count er

% Ar r ay of mean vauesmean_dyno_t orque_ar r ay = [ mean_dyno_t orque_ar r ay mean(Dyno_Torque_3) ] ;mean_r pm_ar r ay = [ mean_r pm_ar r ay mean(RPM_10)] ; mean_MAF_ar r ay = [ mean_MAF_ar r ay mean( MAF_13) ] ;

mean_t hr ot t l e_pr cnt _ar r ay = [ mean_t hr ot t l e_pr cnt _ar r ay mean( TPS1Per cent _13) ] ; mean_MAP_ar r ay = [ mean_MAP_ar r ay mean( MAPTi me_10) ] ;

f i gur e( ' col or ' , [ 1 1 1] ) pl ot( t i me_12, PreCatO2_12, ' b' ) gr i d onxl abel ( ' Ti me( s) ' ) yl abel ( ' Pr e- Cat al yst Equi val ence Rat i o' ) t i t l e( [ ' Pr e- Cat al yst Equi val ence Rat i o vs Ti me( s) ' num2st r ( f i l e_num( a) ) 'kPa' ] )

end

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% Pl ott i ng Aver age var i abl es vs Aver age t hr ott l e per cent age.

f i gur e( ' col or ' , [ 1 1 1] )

pl ot ( mean_t hr ott l e_prcnt_ar r ay, mean_dyno_torque_arr ay, ' o- r ' , . . . mean_t hr ott l e_pr cnt _ar r ay, mean_r pm_ar r ay, ' o- b' , . . . mean_t hr ott l e_pr cnt _ar r ay, mean_MAP_arr ay, ' o- k' , . . . mean_t hr ott l e_pr cnt _ar r ay, mean_MAF_ar r ay, ' o- g' , . . . ' l i newi dt h' , 1. 5)

gr i d onxl abel ( ' Aver age Thr ot t l e Per cent age ( %) ' )

yl i m( [ - 200 1200] ) l egend( ' Dyno Measur ed Tor que( f t - l b) ' , ' Engi ne Speed( RPM) ' , . . . ' Mani f ol d Ai r Fl ow Rat e( kPa) ' , ' Mani f ol d Ai r Pr essur e( kPa) ' )

t i t l e( ' Aver aged Vari abl es vs Thr ott l e Per centage( %) ' )