The Dearman Engine
The Problem
It is no great secret that our well-being is tied to, among other things, the contents of our air. Currently, cars, coal-burning plants, diesel-powered machines, and more are releasing dangerous amounts of Nitrogen Oxides, or variants of NOx, into our atmosphere. These chemical compounds are known green house gasses and also serve as long-term health risks.
This is clearly an issue, but what are we doing to solve it? One tech company, Dearman, has designed a new engine for peripheral systems . The so-called Dearman engine will be able to replace many diesel counterparts in cooling, heating, and power applications.
The Engine
The Dearman engine draws information from the Industrial Revolution’s steam engines – but with a twist. Instead of heating water, causing it to expand and push a piston, the engine heats up liquid nitrogen with air and hot water. During this process, the liquid nitrogen expands to 710 times its initial volume, making it much more effective than steam engines. Click on the image below to see the process as a GIF.
The engine works much like current combustion engines. As portrayed in the images below, there are 4 main stages to the stroking process. The first step of this process begins when the piston is in its ‘Return Stroke’. During this time, the piston pulls warm water into the chamber.
During the upstroke, the water is compressed and, in a position described as ‘Top Dead Centre’, the liquid nitrogen is pumped into the chamber. The nitrogen becomes gaseous, expanding rapidly with a relatively stable temperature (the reaction is largely isothermic).
The expansion of the gas pushes the piston down in the ‘Power Stroke’, turning the drive shaft. Finally, the momentum of the drive shaft pushes the piston upwards, expelling the gas and water out of the chamber. The piston then travels downwards, and the process begins again.
The Environment
Most engines emit CO2 and NOx gasses, which are harmful to the environment — and your health! The Dearman engine, however, solves this issue. The now-cooled water is recycled within the system and the nitrogen gas is exhausted. Atmospheric nitrogen, which has decreased as a result of human civilization (replaced by nitrogen compounds), is extremely beneficial to the ecosystem.
This engine not only ceases to emit nitrogen compounds, it also emits much-needed nitrogen back into the atmosphere.
The Applications
Dearman has already begun using their engine to power a variety of systems. Under the projects section of the website, the company discusses their current ventures.
The Transport Refrigeration Unit (TRU): The Dearman Engine, with its liquid nitrogen system, is ideal for cooling applications. The engine is quieter, quicker, and more efficient than its diesel counterparts — plus its clean!
The Dearman Generator (Genset): While the Dearman Genset is still in its design phases, the company hopes it will surpass diesel generators in both efficiency and emissions. The generator, because its functioning is liquid-nitrogen-based, will also provide a unique service to environments that need special cooling.
The Dearman Heat Hybrid (DHH): The Dearman Heat Hybrid is the company’s vision of a diesel-Dearman hybrid. The waste heat generated by the diesel engine can be used by the Dearman engine to increase its efficiency. Already, there has been rigorous testing of a large hybrid bus, with promising results.
The Future
The Dearman engine promises much, but it still has a long way to go. A big leap will occur when the engine gains enough power to fully operate a car — and it is only a matter of time. As mentioned above, the company has already successfully tested a hybrid engine for a bus. Technologies like the Dearman engine are entering the market at an encouraging rate, and it seems many of them are promising increased efficiency over their polluting counterparts.
For more technologies like the Dearman engine, check out this post on Policy Exchange:
https://policyexchange.org.uk/6-new-technologies-which-could-improve-urban-air-quality/