The Industrial Trent, which is the most powerful and efficient aero-derivative gas turbine, is used primarily in two important markets, power generation and oil and gas. Both markets value the ability of this product to generate clean, efficient electrical or mechanical power, which ever is desirable.
To enable the Industrial Trent to operate with very low emissions at maximum power a number of enabling technologies have been developed.
In order for the combustion system to operate with the lowest emissions it must operate at a specific flame temperature, balancing the generation of oxides of Nitrogen (NOx) with the generation of Carbon monoxide (CO). This is very difficult if fuel and air are injected (diffused) directly into the combustion chamber, and therefore a technology known as pre-mixing is utilised. The fuel and air are (pre) mixed to create a uniform mixture that, once it enters the combustion chamber, is ideal for complete low emissions combustion.
Achieving low emissions also brings the problem of combustion noise. Noise is generated when the flame in the combustor is operating very lean, where flame pertubations (oscillations) couple with the natural frequency of the surrounding components. A similar phenomena happens when a musical wind instrument is played, where the pertubations of the air blown into the mouthpiece couple with the natural frequency of the instrument. Rolls-Royce has developed a passive damping technology to address this destructive force, where dampers of specific natural frequencies literally ‘cancel out’ the force.
To enable the industrial Trent to generate as much power as possible, Rolls-Royce have also developed an Inlet Spray Intercooling System, where clean water droplets are injected into the compressor. As the water droplets continue through the compressor they ‘cool’ the air, which is beneficial for the engine thermodynamically. This is because the cycle requires much less energy to compress cooler air than hotter air, leading to more energy for the customer.
Spraying water droplets into the front of an engine that is rotating at up to 10000rpm can lead to significant damage, in the form of erosion. To address the issue of erosion Rolls-Royce applies it expertise in aerodynamic design to strategically place water droplets in specific places in the compressor.
Rolls-Royce, in conjunction with its suppliers, has also developed various specialist coatings to counteract the destructive force of erosion, allowing for maximum power extraction.