Table of Contents
How do you calculate actual air/fuel ratio?
Calculating the Ratio
- So 1 molecule of methane has a molecular weight of: 1 * 12.01 + 4 * 1.008 = 16.042.
- One oxygen molecule weighs: 2 * 16 = 32.
- The oxygen-fuel mass ratio is then: 2 * 32 / 1 * 16.042 = 64 / 16.042.
- So we need 3.99 kg of oxygen for every 1 kg of fuel.
How do you calculate LHV and HHV?
Under this formula, the relationship between the lower heating value of a fuel and the higher heating value of that fuel is: LHV = HHV – 10.55(W + 9H) Where: LHV = lower heating value of fuel in Btu/lb, HHV = higher heating value of fuel in Btu/lb, W = Weight \% of moisture in fuel, and H = Weight \% of hydrogen in fuel.
How do you convert GCV to NCV?
Calculate a) Gross calorific value, moist basis b) Net calorific value, dry basis c) Net calorific value, moist basis d) Gross calorific value, dry basis using Dulong formula. = 32060.2 KJ/Kg NCV = GCV – 24.44(9×\%H + \%M) = 30630.26 KJ/Kg Thus NCV = 0.955 times GCV in this case. 3.
What is the air fuel ratio in petrol engine?
about 14.7:1
The theoretical air–fuel ratio mixture for a gasoline fueled engine, for complete gasoline fuel combustion, the stoichiometric air–fuel ratio is about 14.7:1. In order to completely burn 1 kg of gasoline fuel, the combustion process needs 14.7 kg of air.
How do you calculate the lower heat value of a fuel?
We compute the lower heating value (LHV) as the difference in enthalpy (per kg mixture) between reactants and products at constant temperature and pressure, divided by the mass fraction of fuel in the reactants.
How do you calculate the fuel mass flow rate?
From the fuel to air ratio, we can obtain the fuel mass flow rate by a simple multiplication. f = [(Tt4 / Tt3) – 1] / [(nb * Q) / (cp * Tt3) – Tt4 / Tt3] mdot f = f * mdot a The engine air flow rate is normally set by conditions in the nozzle. We can use the value of fuel to air ratio to determine the engine’s specific fuel consumption.
LHV = HHV – 10.55(W + 9H) Where: LHV = lower heating value of fuel in Btu/lb, HHV = higher heating value of fuel in Btu/lb, W = Weight \% of moisture in fuel, and H = Weight \% of hydrogen in fuel.
What determines the engine air flow rate?
The engine air flow rate is normally set by conditions in the nozzle. We can use the value of fuel to air ratio to determine the engine’s specific fuel consumption. As explained in another section of the Beginner’s Guide, the specific fuel consumption and the aircraft fuel load determine the maximum flight time and the maximum range of an aircraft.
How do you calculate the heat input of a piston?
In order to determine the heat input, Qin, in [J], the mass of the fuel entering the piston has to be calculated. The equivalence ratio can be expressed as: If the equivalence ratio is given the above relation can be solved for the actual mass of the fuel.