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September 18, 2014, 02:36 
emission parameters

#1 
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ABDUL GAFOOR CP
Join Date: Jul 2014
Posts: 30
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hiii.....
In AVL we are getting the emission parameters as mass fractions only....can anybody suggest me the procedures to convert this mass fraction into g/kg of fuel or g/kWh units..... thanking you gafoor 

November 23, 2014, 18:10 

#2 
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Farhad Hossain
Join Date: Aug 2014
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Calculate the total number of moles in the exhaust gas from the volume flow rate(m3/hr) of exhaust gas using the ideal gas law PV=nRT.
Number of moles in the exhaust gas flow, n =RT/PV, where R (R = 8.3145 J/mol·K) isideal gas constant, V is exhaust flow rate in m3/hr, P is pressure in N/m2 and T istemperature in K. 2. Multiply by the ppm value (y*106, assume y is measured ppm of gas) for eachspecies of pollutant to get the moles per hour of that species 3. For each pollutant species, multiple by the molar mass (molecular weight) to getgrams per hour. Divide by power output in kW to get grams per kiloWatthour I have also attached a calculation file for your understanding. 

November 24, 2014, 04:35 

#3 
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ABDUL GAFOOR CP
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thanks a lot for your valuable information.....
regards gafoor 

November 24, 2014, 04:59 
emission parameters

#4 
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Farhad Hossain
Join Date: Aug 2014
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Hi gafoor
Do you help me about AVL Fire Spray and Combustion program? Best regards farhad 

November 24, 2014, 05:25 

#5 
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ABDUL GAFOOR CP
Join Date: Jul 2014
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hii...
i am also very new in AVL and also in CFD. though i will try my level best to help you.. feel free to ask me about your problems and we will discuss.... my mail ID is gafoorcp@yahoo.com regards gafoor 

January 29, 2016, 19:33 
Are AVL Fire emission results correct ?

#6 
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muhammet
Join Date: Jan 2016
Location: istanbul
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Hi all,
i am using AVL fire but i am doubtful about the results of emissions. i did some simulation and tuned the cylinder pressure with exp. but the emissions did not tuned. i use extended zeldovich model for NO and one more; when i use the other model for NO, it gives different resuls at same temperature curve. could any one help me? thanks. 

January 29, 2016, 19:46 

#7 
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muhammet
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i thing you can get total mass curve (or data) and then if you multiply the total mass with mass frac. you will get the mass of i species( for ex. NO ). then you must find the value of mass per hour ( with using the engine speed ). then devide it with power.
TM = total mass* injector hole number (because it gives total mass results for only per hole) NO mass = NO mass frac.*TM NO [g/kWh] = {(NO mass)*(n/2)*60} / power ! engine speed must devided by 2 if it 4 strokes ! 60 is represent the minutes in hour. 

April 6, 2016, 00:26 

#8  
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Join Date: Feb 2013
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Quote:
Paste the following code in a notepad and change the file extension from *.txt to *.frml (frml is the extension which works as a formula file for AVL FIRE) Upload this formula and you will get the NOx values in ppm directly //  NOx_ppm.frml  // Must be used with cellselection only! // Computes the average NOx concentration in [ppm] according // to the specified assumed molar mass of NOx as fl2 result; // molar mass of NOx in g/mol #define REAL_assumed_molar_mass_of_NOx 38.0 $$init double ppm_nox = 0.0; if(!init){ if(divisor > 0.0) ppm_nox = sum / divisor * 1.0e6; if(IAMPRO < 2){ print "NOx_ppm.frml: avg NOx concentration in", name, ":", ppm_nox, "[ppm]"; } sum = ppm_nox; divisor = 1.0; } $$formula divisor += ap * vol / (8314.4 * temp); return YNOXMF[index] * den * vol / REAL_assumed_molar_mass_of_NOx; Once you get the NOx ppm values from above formula use the following: NOx (gm/hr) = 0.001587 * NOx (ppm) * Exhaust Flow (kg/hr) and NOx (gm/kWhr) = NOx (gm/hr) / Power (kW) Since ESE diesel calculates BSFC (gm/kWhr) , Power (kW) and AFR, you can get following a) Fuel Flow = BSFC (gm/kWhr) * Power (kW) = Fuel Flow (kg/hr) b) Air Flow (kg/hr) = AFR * Fuel Flow c) Exhaust Flow (kg/hr) = Air Flow + Fuel Flow Please note all the above calcluations do not contain the NOx correction factor which is dependant on humidity, ambient temperature etc which of course cannot be determined by AVL FIRE. Usually the NOx correction factor is 0.94 to 0.95 which will be further multiplied to the above NOx (gm/kWhr) value giving the final answer This is taken from ISO 8178 emission calculation standard In this standard the engine power has weightage factors which I have not considered here.. (for simplicity ) 

July 6, 2016, 12:23 

#9 
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amin u3fi
Join Date: Feb 2013
Posts: 60
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I used this formula but it does not work. could you please send me the .h file?
amin_u50@yahoo.com 

Tags 
avl fire, emission, mass fraction 
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