The new mtu 12V and 16V 2000: High Tech for high Speeds

• Intelligent Engine Concept
• Third Generation of the Common Rail Injection System
• New, Powerful Turbocharger System
• New "ADEC" (Advanced Diesel Engine Control) Engine Electronics

The 12V and 16V 2000 Common Rail engines presented at the International Miami Boat Show set new standards for the yacht market. Especially the 16V opens up a new power segment because it covers a power segment which didn’t exist in that size class before. The engines also show characteristics which set them apart from anything else in the yacht industry: Extremely low weight, small dimensions and low fuel consumption. mtu made this possible by using state-of-the-art technologies. The basic concept as well as the key technologies of turbocharging, injection and electronics have been redeveloped and advanced.

Intelligent Engine Concept

The favorable power-to-weight ratio of 0.71 HP/kg (16V) and 0.64 HP/kg (12V) of the 2000 Common Rail engines goes back to a high power per cylinder and the extensive use of light alloy. The weight optimization of components and the modular design of the engine are also important factors. In several parts in the 2000 Common Rail engines, more than one function is integrated into the same component. This reduces weight and saves space. One example of this is the engine Vee, which together with the outer wall of the charge air cooler situated above it forms the ducting for the charge air flow, which goes from the turbochargers to the charge air cooler. Such a design was possible because a common rail injection system is used, and the space in the engine Vee (90 degrees) is therefore not occupied by injection pumps.

Third Generation of the Common Rail Injection System

The 12V and 16V 2000 Common Rail engines employ a third generation common rail system in which an accumulator is mounted on top of the injectors. The actual storage function is performed by individual storage facilities in the cylinder heads. This prevents pressure fluctuations in the fuel line, thus stopping surging at the injectors and the supply of too little or too much fuel. The pressure (max. 1800 bar) remains virtually constant in the entire system. In addition, the fuel lines have a smaller and, in the standard version, single-wall design. The fuel line is situated inside the charge air pipe, and is thus surrounded by a second layer.

mtu - as the first manufacturer in the industry - has been using the powerful common rail injection system in its engines with great success since 1996. This technology has now become the standard in the automotive sector, and was recently also brought into use by competitors in the off-highway/marine sector. As a result of our positive experience with this system, mtu has again used a common rail system in the 2000 Common Rail. However, it is an advanced version of the third generation.

New, Powerful Turbocharger System

The 12V and 16V 2000 Common Rail engines are fitted with a powerful turbocharger system, in which three turbochargers are used. Only one turbocharger runs at low engine speeds; the second and third turbocharger are only engaged electronically at higher engine speeds. This sequential turbocharging ensures a powerful charge air flow and therefore an immediate and strong engine acceleration response across the entire performance map. The efficiency of the turbocharging system is enhanced by the integration of the charge air cooler into the engine Vee, as this shortens the path of the charge air flow.

The ZR 125 turbochargers were developed by mtu, and are also manufactured in-house by the company. At a maximum turbocharger speed of 85,000 rpm, they build up a maximum charge air pressure of four bars, a pressure that is otherwise only achieved by complex two-stage charging systems in engines of this size. The compressor wheel is made of aluminum, which has a positive impact on the acceleration performance of the turbochargers because of the low weight. The compressor wheels of the turbochargers are housed in a water-cooled carrier housing, which keeps the surface temperatures below the level of 220 degrees Celsius stipulated by the SOLAS regulation (Safety of Life at Sea).

New "ADEC" (Advanced Diesel Engine Control) Engine Electronics

Another major innovation in the new mtu 2000 Common Rail series is the new generation of mtu's own "ADEC" (Advanced Diesel Engine Control) electronic engine management system. During the in-house development of the units, the diesel engine was regarded from the very start as an integral component of the propulsion system. Consequently, the engine can be easily integrated into the power train. To achieve this, in addition to the engine controller, a system interface was developed, which provides shipbuilders with a wide range of capabilities and advantages. The controller was given a far more robust structure than previous units, with the result that it is even more suited to all the different conditions in the engine.

Technical Data of the New 12V and 16V 2000 Common Rail Engines

Number of cylinders	12 / 16
Engine output for yachts and fast ships	1344 /1792 kW (1800 / 2400 HP)
Power per cylinder	112 kW (150 HP)
V angle	90 degrees
Bore/stroke	135 mm/156 mm
Displacement per cylinder	2.23 liters
Idling speed	600 rpm
Maximum engine speed	2450 rpm
Turbocharging	Single-stage sequential turbocharging with two or three turbochargers, charge air cooling, water-cooled compressor wheels
Injection	Common rail with individual storage volumes integrated into the injectors
Cooling system	Mixed circuit
Valve control	Four valve design with a centrally arranged camshaft
Cylinder cut-out system	Optional, electronically controlled