Ready for the next emissions stage

30 Dec 2011
The new generation of MTU’s series 1163 engines sees a newly developed version of the engine, without exhaust after-treatment, seen here in the: 20-cylinder version

The new generation of MTU’s series 1163 engines sees a newly developed version of the engine, without exhaust after-treatment, seen here in the: 20-cylinder version

The further development of MTU’s series 1163 engine for the IMO Tier II limits is described by Christoph Fenske, senior manager, application center marine, naval surface craft at MTU Friedrichshafen.

Since the beginning of the 1980s, the MTU series 1163 has been one of the most widely used engines in naval shipping. For compliance with IMO II, an advanced version of the unit without exhaust treatment systems is to be launched. The future version will retain all the decisive engine characteristics of its predecessors that were so important to customers. This means that reliability, high power density and optimum acceleration capabilities will remain the key features of the series 1163.

Having been designed for lighter weight and greater power than comparable engines, the series 1163 fast-running large-scale diesels have been successful for close to 30 years. Developed for naval installations and later adapted for use in commercial vessels, the series 1163s have proved reliable and potent in global applications. To ensure the engine continues to meet the requirements of the IMO Tier s II and III regulations, MTU is upgrading the 1163 design.

Development aims

Despite the strict emission restrictions, the efficiency of the engines cannot be compromised. New engines must demonstrate the same qualities as the previous version in terms of key engine characteristics such as reliability, high power density and rapid acceleration. And they must do so using substantially less fuel than before. The interfaces are to remain virtually unchanged so that clients can continue to use the engine in ships and ship designs that are currently planned or in service — and continue to enjoy the high power-to-weight ratio and small footprint.

The proven system components are to remain virtually identical. For the 04 version of the engine (1163 M04), three out of four components will be carried over directly from version 03 (1163 TB03). So existing stocks of spare parts and add-ons such as resilient mountings or acoustic enclosures will still be usable in future. Due to a reduction in the number of mechanical components, less servicing work will be required.

The planned concept will enable the NOx limit of 8.5 g/kWh required by IMO II to be met by internal engine design features alone. From the outside, the changes will not be visible until 2016, when the IMO III NOx emission limit of 2.1 g/kWh comes into force. The version 04 engines, which will be carried over unchanged for the IMO III overall system, will then be provided with what MTU believes to be the best current technical solution for compliance with the emission limits demanded — an SCR catalytic converter which chemically renders the emitted nitrogen oxides harmless.

Ongoing development of the engine will take account of the latest requirements of the definitive classification societies and the navies. The 1163-04 will thus meet specifications such as those of the American Bureau of Shipping (ABS), Det Norske Veritas (DNV), Germanischer Lloyd, Lloyd’s Register of Shipping or the Registro Italiano Navale (RINA) as well as naval demands for features such as low noise and shock-resistant engines in accordance with electromagnetic compatibility regulations.

For use as a main propulsion unit, the three cylinder configurations of V12, V16 and V20 will be retained. That relates to engines in high speed vessels with high levels of capacity utilisation, such as high speed ferries with an average output of 60% to 80% of rated power and up to 5,000h of duty per year. The engines are also designed for ships with medium to low capacity utilisation such as patrol boats with outputs lower than 60% of rated power and up to 3,000 hours of service a year.

Technologies for IMO II and IMO III

In order to upgrade the series 1163 for IMO II and IMO III, MTU will modernise the fuel injection, the combustion process and the electronic engine management. Instead of the old unit-pump system, the advanced version of the series 1163 will benefit from improved fuel injection using an electronically controlled common-rail system with an injection pressure of up to 1,800 bar.

Above all, that will give the engine a better performance map, i.e. lower fuel consumption, lower NOx and soot emission levels and more responsive acceleration. The efficiency of the two-stage sequential turbocharging has been optimised and the future versions of the 1163 will continue to use three (on the V12), four (V16) and five (V20) pairs of turbochargers. The maximum combustion pressure will be raised, which will enable more efficient combustion and, consequently, lower fuel consumption.

The latest-generation of the ADEC (advanced diesel engine control) engine management module enables injection timing, volume and pattern to be controlled independently of engine speed, and a more effective tuning of combustion. The ADEC , which consists of engine management and control systems and a local operating panel (LOP) in the engine room, has been well proven on the series 2000 and 4000. The LOP can be connected to the MTU ‘Callosum’ automation system or a third party integrated engine management system via a CAN field-bus connection with redundant backup.

The new engine design will feature a Miller combustion process. Earlier closure of the inlet valves causes expansion of the cylinder charge and a lower combustion temperature, which has a beneficial effect on NOx emission levels. However, that requires a higher turbocharger boost pressure, which is effected by turbochargers with optimised geometry and low inertia. They are brought into play according to engine load so that vessels are able to accelerate quickly and manoeuvre easily thanks to the large torque reserves. In addition, fuel consumption remains low even at low and medium power levels and negligible black smoke is produced under acceleration.

Modern technology

At present there are more than 550 series 1163 units in service, almost all in naval applications powering frigates and corvettes, either as single units or in combined propulsion systems. As a result of the boom in the market for fast ferries at the beginning of the 1990s, the engine became an attractive proposition in the commercial sector as well and in 1994 was officially presented as a propulsion solution for yachts and ferries.

The modifications that came out of those tough operating conditions substantially increased the engine's durability and reliability. And since then, commercial vessels have been able to benefit from the super-fast acceleration. For example, the Shinas, said to be the fastest diesel-powered passenger ferry with a top speed of 56.3 knots, set a speed record driven by a series 1163 unit. But it is not just in terms of dynamic response that the series 1163 achieves high standards; unwanted noise and vibration in operation have been drastically reduced by specifically targeted engineering.

The latest advancement of the series 1163 design, the 1163 M04, will retain the same successful characteristics of its predecessors, as a modern diesel engine for the civil and naval markets. MTU claims that its high power-to-weight ratio, high power density and ultra responsive acceleration characteristics make it an efficient propulsion solution.

Shipbuilders will benefit from the range of power classes across the 12, 16 and 20-cylinder versions, which can be selected according to customer requirements. Because of the identical interface setup and the small engine footprint, existing ship designs can be implemented without having to reconfigure the driveline and its associated supply systems or repeat the stability calculations.

As a provider of complete system solutions, MTU believes it offers shipbuilders the advantage of obtaining all necessary products from one source. Complete systems consisting of diesel engines, gas turbines, power generators and purpose-built automation systems simplify the procurement process. The new 1163 generation represents efficient, clean and economical propulsion for semi-planing to full displacement craft and from a naval patrol boat to a fast commercial ferry. The engines are equally suited in low/medium power operation scenarios, which are important for naval vessels. In those situations the fuel consumption is especially low.

Ratings and economy

The rated power and speed figures for the future series 1163 models will be similar or identical to those of the present incarnation. Fuel consumption will be considerably lower, especially when operating below full power. Emission levels will also be further reduced to meet the IMO II emission limits, which have been in force since 2011, by means of internal engine design features alone, i.e. without the use of exhaust treatment systems and without any loss of engine performance.

Links to related companies and recent articles ...

MTU Friedrichshafen GmbH

view more