Surely most people have learned about the industrial revolution at some point in their education. One of the most substantial births of this era in American history was the steam engine, and as such an innovation undoubtedly paved the way for further industrial innovations, we now have the luxury of even greater advancements. These innovations include, most notably, diesel powered engines and generators. Pioneered by Rudolf Diesel, diesel power seems to constantly be evolving, most certainly faster than the innovations of a hundred years ago.
Diesel Engine Overview
Perhaps the most noteworthy modern advancement in diesel engine technology has been, and continues to be, improved fuel economy. As it has always seemed to be, gas powered engines have been more widely adopted by the general public. With the constant toggling match over fuel economy, diesel is often largely overshadowed by traditional gasoline usage. With that said, diesel engines have found a solid user base in various forms of industry, especially with those that require fuel economy for large load transportation, back-up power supply, and major agricultural operations, among other things.
Over the last several decades, numerous attempts and successes have been made to better improve the overall efficiency of the diesel engine. Most of these modifications somehow involve the ignition of power within the engine, which is produced from the combination of oxygen and fuel. This concoction eventually produces the necessary energy to ignite the engine.
In contrast, gasoline engines use a spark plug in order to ignite the process. In a diesel engine there is no such thing as a spark plug, in fact, the ignition process is performed directly as oxygen is allowed into the combustion chamber. As it does so, the oxygen is then compressed and heated to a temperature over 1000 Â° F. As fuel is injected into the combustion chamber via a pre-chamber, the heat inside instantaneously ignites the fuel expanding the air in the chamber, which naturally moves the pistons inside. This momentum then drives the crankshaft. Small drops of fuel are also released in the pre-chamber to keep the engine running. The more evenly these droplets are used, the more fuel economy and overall efficiency the engine will have.
At the forefront of diesel engine innovation, are companies such as Caterpillar and Cummins, which provide significant advancements in technology to the industry via their research and development departments. While such companies are doing what they can to further the advancement of engines and diesel generators, it is important to reflect on the innovations that have been made up to this point.
Diesel Engine Alterations
There certainly have been a fair share of diesel engine alterations over the years, including those that directly affect the combustion chamber. More specifically, the pre-chamber and combustion chamber have been modified in recent years for maximum power, giving off a turbocharged result. Expanding on such advancements, digital interfaces have taken the place of previous analog controls. Digital controls provide better fuel injection precision and timing, reducing exhaust emissions.Additionally, more modern technological achievements have been made that assist the transition to emission reducing technology, such as Selective Catalytic Reduction (SCR) and Exhaust Gas Recirculation (EGR).
Recently there have been even greater modifications to the diesel engine combustion chamber, including those that achieve optimal combustion rates, which ultimately provide greater power and better fuel economy with fewer fuel emissions.
Sound modifications have also been made to the diesel engine, including sound attenuation alterations to reduce the noise level that the engines put out and are subsequently synonymous for. Such alterations include fitting ceramic, and other sound wave absorbing materials to noise pockets in the pre-chamber.
Fuel Systems and Fuel Treatments
Along with the aforementioned advancements in diesel engine technology, there have been extensive advancements with regard to fuel systems and treatments; for instance, the Common Rail Fuel system, which was designed for direct fuel injection. Ultimately, this advanced form of fuel injection transfers diesel from the fuel tank to the various valves, while maintaining the highest pressure to homogenize diesel fuel and oxygen as the mixture vaporizes. This process also comes with greater control, power output, and fewer fuel emissions. Additional advancements to this form of fuel injection have introduced methods of using upwards of five fuel injections for each combustion cycle, further increasing fuel efficiency.
With the high contents of sulfur in diesel fuel, there is often a presence of elevated amounts of particle matter in the engine during the combustion process. These particles can clog certain areas of the engine and really hinder overall performance. Thanks to the government mandates and continued research and development of this issue, advancements have been made to lower the amount particle matter, creating a form of diesel fuel with lower amounts of sulfur, which naturally results in fewer fuel emissions from exhaust.
Analog to Digital Controls
As previously mentioned, newer diesel engine models have undergone a switch from analog to digital control technology. While both controls are implemented to monitor or alter the functioning of an engine, each seems to have solidified a place with various size engines. With the advancement of digital technology, diesel powered engines and generators typically involved in larger scale jobs, have made the switch from analog to digital controls in order to better monitor the backup power to similar scale facilities and equipment. However, analog still holds a useful purpose with smaller engines and generators to provide backup power.
Furthermore, the transition of many diesel engines to digital control has provided improved monitoring of fuel and coolant levels, as well as engine oil, temperature, and battery life. The purpose of using a digital control for such monitoring is primarily due to the high amounts of manual effort it takes to adjust and correct engine malfunctions. What’s more, in the case of such a malfunction, analog controls only warn of an impending problem, but do not provide the specific details of what is wrong and how to fix it. This can be a frustrating problem for many involved with the operation of diesel engines and generators.
Such notification, or a lack thereof, may suffice in smaller facilities and on a less critical scale, however, when lives and livelihoods are on the line, digital controls are much more helpful than a mere light-up notification. Using, in some cases, hundreds of digital alarms and notifications specific to a number of different pinpointed issues, primarily makes a diesel engine run smoother. Additionally, such digital technology also makes the operator’s job much simpler, especially with the furthered integration of the Internet. With the increased reliability that digital controls bring, diesel engines are able to continue operation even in the face of a mechanical issue, thus limiting any possible downtime in a facility. If this is not reason enough to praise digital controls, reduced fuel emissions, along with the overall efficiency of adjustments to the engine fuel rate and timing only further the argument for their use. Also, the voltage amount and output frequency features better stabilization when using digital controls.
Closing on the topic of digital controls, it is important to note the intelligent nature they posses in order to carry out proper fuel rate functions during the acceleration process. This, among the many other highly intelligent digitally monitored functions, such as gradual acceleration during rated speed, make digital controls necessary for the highly intuitive equipment used across a wide range of jobs and industries.
Diesel Fuel Emission Treatments
As mentioned earlier, Exhaust Gas Recirculation (EGR) and Selective Catalytic Reduction (SCR) are the most recent advancements in fuel emission treatments. The combustion of diesel fuel happens at extremely high temperatures in which NOx is produced. Such emissions can be extremely hazardous to the environment, which is where the EGR system comes into play. In essence, it is implemented to treat and subsequently lower such emissions being released into the atmosphere. This significant reduction is accomplished by directly recirculating NOx back into the combustion chamber. In the end, the temperature is then lowered, thus reducing the formation of further NOx.
Also previously mentioned, SCR is used as a method of converting NOx so that it is not as harmful to the atmosphere. Long used in commercial businesses, the SCR process is now being implemented with diesel engines and generators, reducing fuel emissions by as much as 95 percent and receiving praise as an environmental improvement.
The advancements in diesel generator sets and engines have begun to take some serious strides in recent years and in a number of different aspects. Whether it is with preventive maintenance or fuel emission reduction, we have certainly come a long way since the methods of the steam engine and the industrial revolution. While the individual advancements of digital controls, fuel emission treatments and engine modifications have undoubtedly been remarkable; the grouping of all diesel engine related advancements has proven to hold more effect on industry than any lone development, collectively bettering the use of diesel.