Gaseous-fuel engines

Hydrogen internal combustion engines can be classified, like any other gaseous-fueled engines, into three basic engine concept categories [56] ... 

Otto-cycle gaseous-fuel engines are characterized by external or internal mixture formation and a timed ignition at a singular point, as, for example a spark plug. Most vehicle applications currently under development and testing fall into the... 

Gaseous-fiiel Diesel engines as well as Diesel gaseous-fuel engines usually require a more complex infrastructure, for example a secondary fuel-system and possibly lean mixture exhaust gas after-treatment systems and are therefore mostly used for stationary power generation. 

Considering the advantages and disadvantages of the above classified engine types, the Otto-cycle gaseous-fuel engine concept has the greatest potential, especially for automotive applications. 

Gaseous fuels containing fractions whose ignition temperature is lower than that of methane may require the use of low-compression heads and a resulting derating of the gas engine. 

When considering the possibility of using internal combustion drivers, evaluate process requirements and costs. If a low-cost, gaseous fuel is available, gas engines and gas turbines may surpass other drivers in economical installation and operation. In the initial process design stage, a method of establishing the cost of purchase, installation, and operation for drivers is needed. 

Internal combustion engines can be operated by a number of liquid and gaseous fuels. Table 3-2 gives the high value heat of combustion for various field available liquid and gaseous fuels [5J. 

Approximate Gaseous Fuel Consumption for Multicylinder Internal Combustion Engines [4,5] ... 

The use of propane as a motor vehicle fuel has been highly developed in some countries, particularly in the USA, Holland and Italy. It is, of course, an entirely lead-free fuel. Very high efficiencies can be obtained using a gaseous fuel in spark-ignition engines since intimate mixing of the fuel and air is much more easily achieved than with a liquid fuel. This results in a much cleaner exhaust, with considerable reductions in CO and hydrocarbons. 

David K Schmalzer, Ph.D., P.E. Fossil Energy Program Manager, Argonne National Laboratory Member, American Chemical Society, American Institute of Chemical Engineers (Fuels, Liquid Petroleum Fuels, Gaseous Fuels)... 

Combustion control is currently a hot area of research in the U.S. and abroad. In addition to basic research at a number of universities, joint industry-university S T efforts are also underway to implement the control strategies developed by researchers in industry applications. Though some of the demonstrations have been made using gaseous fuels, the techniques can be extended to liquid fuels as well, and efforts are underway to accomplish this. It is hoped that future engines will perform equally well in off-design conditions, with improved reliability and easier maintenance, and reduced operational costs. 

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