how to calculate disel consumpation

May I also suggest that you try to learn to use the spelling checker before posting? It would make reading your posts much easier, especially for those not having English as a first language.....

Green tick with ABC on it.

Why do you want to invent the wheel?

Install an on line Flow meter with a totalizer to give you accurate reading on all loads.

These are similar like water flow meters.

Standard weight of #2 diesel is 7.08 lbs/gal, (18,900 BTU/lb)try using 0.4 lbs/brakeHP-hour for efficiency of engine. Of course you need to know Horesepower or kilowatts or some measure of the output of the engine

Satinderbabra asked: I need to know how much fule is consumed by the engien from 'starting to shuting' in that interwell engien use its full power or part of power.

REPLY

Once again a poorly defined and loaded question.

It's hard to provide a good answer when the required parameters are not defined. The suggestion of installing a fuel flow meter makes sense but the cost of such a meter becomes prohibitive when dealing with smaller engines under 200 HP size.

Nothing was said about expected use, duty cycle, or application. Tier II and Tier III engines with computer controlled common rail injection already provide this data from the internal CPU processor. In most cases the fuel consumption can be accessed from the regular engine display (digital) with a few keystrokes on the panel. Some manufacturer only provide the data if you add a laptop computer and data port to the installation. However there are also third party vendors of software that can read the industry standard data protocol.

If the query is related to working with applications using existing older engines which are totally non electric, a very basic approach is to measure consumption by the simple expedient of starting with a full tank - running a measured time interval and then refilling the tank. Measure how much was consumed by using graduated measuring cups. remember that th elon ger the measuring interval the more accurate the overal lmeasurement result.

I have found the formula for fuel consumption by weight using 0.34lb (imperial) per brake horse power per hour to be more accurate than the 0.4lb/BHP/Hr assuming using #2 diesel fuel.

regards

Elnav

Sir, As some other friends are telling your question is not quite well specified.

First of all every engine have specific performance curves (such as efficiency curve) and a nominal fuel consumption in g/kwh (grams per kilowat hour in SI-system). You have to know the fuel quality as well such as thermal value in kwh/kg. Now you can find the engine efficiency as per the curve when you know the revolution and by knowing the efficiency you can multiply the thermal value and you will know the momentanum fuel consumption. By installing a flow meter with totalizer in the fuel line you will know only a feeded amount in liter, which must be multiplied with the specific gravity of the fuel in kg/dm3, because in fact you want to know how many grams of kilograms you will consume. In every diesel engine you will also have a certain amount returning to the tank. This amount must be measured as well. Therefore its recommended to use a mass flow meter.

I hope this will help you in your calculations.

All the best Kari U. Laiho

36. Hope that answers your question. :)

You say 'calculate', so is this a prediction for a yet-to-be-installed system? If the system exists it's a case of measurement in the manner previously indicated.

If you want a prediction presumably you have some duty cycle in mind? You can work it out from your proposed duty cycle, say you plot the energy consumed by the load against time, integrate the curve, divide by the calorific value of the fuel but you will need to apply a factor for the thermal efficiency of your engine (and any mechanical losses in transmission). Engine manufacturers will be able to help here, about 35% for a diesel would not be too far out.

Before a farm tractor can be sold in Nabraska it must be tested at the Univeristy of Nabraska. They have every tractor's records they have tested. The easy way is to take the engine type you need data on and find what piece of farm equipment it was used in. Then go online and the data is yours.

Tom Silver

What a great resource! I expect there's a point to that, beyond practice for students on the dyno? Is it for consumer info in making buying decisions?

A "Rule Of Thumb" for Diesel Fuel Use is:

1 Gallon per hour per 20 horse power generated.

So, a diesel engine generating 10 HP would use .5 gallons per hour.

At 35 HP output it would use 1.75 gallons per hour.

I have been using this formular for 40+ yars and have compaired it with flow meter readings and it is really close.