Ever wonder what happened to steam, at least steam powered mobile applications. Diesel-electric trains began replacing steam after the second world war. Diesel is more efficient when small scale power is demanded. Stationary large scale generating plants using steam turbines are the norm for the local power utility. But diesel is king on the move or for smaller power generation applications, like generators. Diesel has been around for over a century. Darwinian evolution drives diesel technology. From electronic controls to the basic machinery diesel technology is constantly improving. Chambers and pre-chambers. The head design is one of the areas that is driving combustion chamber design. On the compression stroke the cylinder volume is reduced compressing the air. At fully compression this may be as high as 1,000 0F, hot enough to vaporize and ignite diesel fuel that is injected at high pressure into the pre-chamber allowing the controlled wave front to progress throughout the combustion chamber. As such combustion chamber shape and design is a primary area of diesel engine research. Combustion rate determines power output, faster the rate the higher the power produced per stroke.
Advanced in Diesel Generator Efficiency
Rapid high temperature combustion rate also extends fuel efficiency and lowers exhaust emissions. Nitrous oxide (NOx) emissions are the primary target of reduction and soot. Exhaust gas recirculation (EGR) and Selective Catalytic Reduction (SCR) are two of the most recent technologies that allow the diesel engine to breathe green.
Noise, many are that object to diesels because of the noise produced. New technologies address noise attenuation is in the works. Most objectionable noise made by the diesel is on start up. Pockets, sound attenuation pockets that is, surround the pre-chamber. These pockets nullify the detonation waves caused during combustion. Some are filled with ceramic pellets. Porous or metallic these are coated with platinum or rhodium that act as catalysts leading to complete combustion of the fuel and attenuate noise levels. Porous ceramic or sintered metallic material line the passage from the pre-chamber to chamber also assist in lowering the noise levels. Modern diesels are not as loud as the used to be.
New Innovations in Diesel Fuel
Fuel, not the sulfurous mess of the past. Then there is particulate matter, i.e. soot. It clogs emission control devices and hampers performance and efficiency. The new fuel D2 or number 2 diesel has reduced sulfur content to 15 part per million and is called ULSD or Ultra Low Sulfur Diesel. Fuel delivery via a common-rail injection system. Common-Rail Fuel (CRF) injection is a form of direct chamber injection that uses high pressure common rail (versus individual lines) and utilize electrically actuated solenoid or piezoelectric valves versus the mechanical cam actuated valves of earlier engines. The common rail systems deliver high pressure fuel which homogenizes the fuel-air mixture by providing a finer mist or vaporized fuel into the pre-combustion chamber. More complete fuel combustion, better fuel efficiency and more power, as well as fewer pollutants. CRF injection is credited with a 5% reduction in fuel consumption and 20% reduction in emissions. With electronic controls up to five injections occur instead of one big one, enhancing combustion.
Diesel Generator CPU (Central Processing Unit)
Fact is electronic engine control has near revolutionized the internal combustion engine as far as fuel economy, power and lowered emissions. This applies to both gasoline spark ignition and diesel compression ignition engines. Various sensors monitor pressure, rpm of the engine, load, temperature, O2 content and other parameters. Sensors sends the data to a CPU that controls the injectors to adjust the injection pulse to match engine performance to the condition encountered and operates on a continuous feed-back loop. Sensor develop what current parameters feed the data to computer, computer adjusts controls and then the sensors send new and there the loop in continuous. Analog (i.e. dials, speedometers, tachometers are analog. Numbers are digital, and exact. Analog is approximate.
Electronic technologies are driving engine development, but the newer mechanical components contribute to the efficiency as well.