NOMEN OMEN TECHNOLOGY

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1 Costantino Radis NOMEN OMEN Volvo has always linked its name to comfort and safety. In all brands. And Volvo Penta is no exception with the new D13-1 marine engine also available in the D13-IPS135 version. An engine for high-performance that meets the requirements for limited space and noise and vibration reduction of builders of yachts from to 12 feet. In the collective imagination, the name Volvo calls to mind the two basic concepts of safety and comfort. From cars to industrial vehicles and earthmoving machines, the products of this Swedish brand carry forward these important values. A constant effort over time has helped to maintain high research and development standards that are in line with these values, thus greatly increasing the brand worth. A vocation for the true needs of the end user that, even with the simple supply of engines, always maintains a precise focus. Volvo Penta marine engines have evolved over time with the key points of reliability, reduced consumption and comfort always being inalienable objectives. In any power range. With the new D13-1, Volvo Penta has provided an even better response to the demands of yacht builders: the smallest possible bulk, the best possible performance, the lowest possible fuel consumption and noise. A veritable egg of Columbus which, on the basis of the excellent and hyper-tested 13 L six cylinder, gives its best in a marine version. And which, with its 1 hp, attacks the upper category from below thanks to features that make it unique. It s not just an engine but also a propulsion system with the name D13-IPS135 which goes well beyond just the engine and broadens the already well appreciated exclusive IPS range. Performance obtained with great care The D13-1 literally drives Volvo Penta towards a higher category though it has the same compact design as the D13-9. As a result of even more extreme engineering that has redesigned a large number of details, this engine uses new injectors that improve combustion. If the starting point of the D13 is obviously the same, the new engine introduces new solutions that mark a big break from the past, introducing a new camshaft with better performance. The pistons are in Monotherm steel with longer life to support the increase in power. The piston rods have obviously been modified and the cooling circuit has been enlarged. The oil cooler is also more powerful to meet EU VI regulations. Modifications to the radiator also involve the exhaust manifold which was adapted to optimise the performance of the new cooling package. Optimisation of the entire cooling system has increased performance. To improve the performance of each component, the oil filters are shorter to guarantee a quicker and efficient flow and better lubrication. This benefits above all the components that demand greater attention, such as the turbines. But that s not all. Careful interventions in the D13-1 have led to a new vibration damper on the driveshaft which ensures longer life and, obviously, greater comfort. Together with other improvements that involved the exhaust system, the discharge valve and the EVC E3 control system, performance in terms of torque and power has increased significantly. The power, compared with the D13-9, has increased by 11% to 1 hp, which can be fully exploited between 2 and 24 rpm. Torque has increased by 8% to 3,527 with a peak around 18 rpm and a favourable curve between 1,-2,2 rpm. An integrated system for maximum optimisation The IPS system is Volvo Penta s response to demand for manoeuvrability, cheaper running, lower noise and space optimisation. And so also the D13-1 had to have a version with twin, forwardfacing, counterrotating propellers and orientable transmission. 39

2 12 1 POWER +11% 8 4 The power of the D13-1 is 1 hp, 11% more than the D Power 9 (hp) Power 1 (hp) IPS135 is the power unit that uses the IPS3 pod, an upgrade of the IPS3 that identifies the four units available for the D13 engine. The new features that give an increase in power are a larger pinion bearing and a new vertical transmission shaft. Reliability has been increased by a toothed wheel integrated in the upper cylinder, thanks to the increased performance of the oil pump which now has an outer shell in metal and a bronze bearing supporting the steering shaft that simplifies installation and makes it safer. Thus work has been done on parts that may seem secondary but, in fact, are fundamental for the overall optimisation of the entire system, reducing power loss and increasing reliability. Last but not least, the unification of the upper element that is common to all IPS systems, from the IPS15, through the IPS2 and to the IPS3. The characteristics of the IPS135 with six cylinders in line are a maximum power of 1 hp at 24 rpm and the possibility to install it in combination with one, two or three other units. Cruising speed covers the interval between 25 and 42 kn. The system can be used with the counterrotating propellers patented by Volvo Penta for these propulsion systems which, as is widely TORQUE 3527 Nm (22 Ib ft) +8% 9 Torque 9 (Nm) Torque 1 (Nm) The increase in torque compared with the D13-9 is 8% at 3527 Nm. The most favourable curve is around 2 rpm. The opinion The new D13 1hp makes Volvo Penta the ideal partner for yards building yachts from to 12 feet, thanks to the compactness of the engine and its high performance. The efficiency of the IPS makes it possible to reach the same top speed with a smaller engine. Compared with inboard installations, the IPS135 version also guarantees a range of up to 4% higher and fuel savings of 3%: with up to 5% less perceived noise, less vibration and more space on board, the D13 1hp offers considerable added value in terms of comfort to the more discerning owner. Nicola Pomi, Volvo Penta Head of Marine Market, Italy. The Volvo Penta IPS range has been on the market since 25 and has become a benchmark in yachting thanks to engineering that was specifically designed to achieve of driving and economic running. 4

3 Handling with a joystick is comfortable, simple and intuitive. The integrated Volvo Penta IPS systems aim for safe use of the vessel. The conception of the IPS system permits simple and intuitive manoeuvres in port increasing safety and comfort. The proximity starter key permits rapid and easy starting. known, pull the vessel forward rather than pushing it, resulting in a high level of comfort. Control is completely intuitive, a truly revolutionary and unique feature of the IPS system introduced by Volvo Penta in 25, thanks to the various driving modes available including, in particular, those with the joystick and single levers. This is not all. The advantages in terms of propulsion efficiency, an almost total absence of exhaust fumes and no cavitation make these systems particularly suitable for safe, comfortable sailing with intuitive handling. An attack from below The light weight and compactness of the IPS135 have led Volvo Penta to attack power segments as much as 3% higher thanks to its performance. A new concept that is valid both for complete IPS units and for simple inboard engines which, instead of an integrated propulsion unit, feature a ZF5 A or, as an optional, a ZF5 IV reduction unit. Obviously the most extreme optimisation comes with the IPS system which guarantees, in the same conditions, a 4% higher cruising range, a 2% higher top speed and 3% lower fuel consumption and CO 2 emissions. The perceived noise is 5% lower, ensuring a comfort that is fundamental in yachts. Another basic element is the compactness of dimensions and weight. This is fundamental for saving space to use for other purposes rather than sacrificing it for the engine room. Volvo Penta has carried out accurate tests of consumption, yield and comparison in terms of weight and bulk between the new D13-IPS135 and a 13 hp engine (thus with 36% more power) with a torque of 455 Nm developed by an engine with a capacity of more than 2, cm 3. The comparative test was carried out in two identical Azimut 68S yachts and generated decidedly interesting results which highlighted how light weight and efficiency are the two features of undoubted value on which the D13-IPS135 bases its strength. 41

4 The IPS system takes up less room on board, and offers functions and overall efficiency in terms of less noise, less vibration and lower consumption. FUEL I/h, 5, 4, 3, 2, 1,, FUEL CONSUMPTION (I/h) D13-IPS Boat speed (kts) 3 4 FUEL I/h 16, 14, 12, 1, 8, 6, 4, 2,, FUEL CONSUMPTION (I/Nm) D13-IPS Boat speed (kts) 3 4 Sound pressure level [db(a) re. 2 µpa] VP DRIVER 55 25kts -6bB(A) Consumption of the D13-IPS135, both in litres/hour or in litres for each Nm of torque, was much lower than that of the competitor thanks to such intrinsic characteristics as the six cylinder architecture, smaller capacity and lower power. A comparison (almost) between equals The first difference between the two engines is the capacity. The engine used for comparison had a capacity of 21,93 cm 3 against the 12,78 cm 3 of the Volvo D13-IPS135. Their power was respectively 13 hp at 23 rpm and 1 hp at 24 rpm. The difference in torque was also remarkable with 455 Nm for the larger V12 and 3527 Nm for the D13-IPS135 with six cylinders in line. But the Volvo Penta engine had a favourable torque curve compared with the power curve. The specific declared consumption was 221 g/kw for the competitor s engine and 211 g/kw for the D13- IPS135. A minimal difference, especially as we consider capacity, power and torque. But we must also bear in mind that these values were read on the test bench in standard conditions. When we come to speak of effective consumption it will be noted that other factors, often forgotten or undervalued, will be decisive. The overall weight of the vessel with the two different installations, differing only in the propulsion unit and obviously the power chain, are the first data that give important indications. With the larger and more powerful engine, the weight reached 36,22 kg with a full tank and no water on board. With the Volvo Penta D13-IPS135 the weight was 34,628 kg, again with a full tank and no water, so there was a difference in weight of 1592 kg. Effective fuel consumption was 263 l/h for the 13 hp V12 versus 185 l/h for the D13-IPS135, with a difference in favour of the six cylinder in-line engine of 78 l/h. In regards to top speed, the D13-IPS135 went 1.3kn faster than its competitor, with an effective consumption of 185 l/h compared with 263 l/h of the larger and more powerful engine. At speeds of Sound pressure was on average lower than that of the competitive engine. At a cruising speed of 25 kn it was 6 dba lower with a decidedly lower perceived sound intensity. between kn the consumption of the V12 engine was up to 5% higher. At the cruising speed of 25 kn the torque produced by the Volvo Penta D13-IPS135 was 313 Nm compared with 2 Nm for its competitor. And that s not all. The D13-IPS135 reached 25 kn 5.4 seconds faster. Moving onto the noise factor, the result was expected, especially taking into account the characteristics of the Volvo Penta IPS system. But the actual data may well beat the highest expectations. The two parameters that were considered are the sound pressure and the index of articulation, which respectively give indications on the noise reaching the ear and the perception of a conversation in a noisy environment. The sound pressure curve showed an almost constant difference in favour of the D13- IPS135 which, at its cruising speed of 25 kn, was 6dBA, with 77 dba from the competitor against 71 dba from the Volvo Penta. Bearing in mind that the decibel scale is logarithmic, the difference is significant. The articulation index is measured in percentages with the maximum (1%) indicating the best conditions for understanding a conversation and the minimum (%) the worst. Starting from minimum rpm the curve of the D13-IPS135 reached 95% against the competitor s 85% and at maximum RPM the difference was slightly greater. The Volvo Penta engine reached 39% and the competitor s one 25%. But the most important fact, besides the fact that the acoustic well-being guaranteed by the D13- IPS135 is certainly greater, concerns the way the two curves develop. The curve of the Volvo Penta is regular and interpolation with a straight line is the logical analytical consequence. The competitor s curve has a significant rise in the early part, reaching 55% (the limit of the comfort zone) already at 1 rpm against the 185

5 Articulation index [%] DRIVER VP Velocity [mm/s rms] (1-1 Hz)] VP,Seat ex VP,Seat ey VP,Seat ez,seat ex,seat ey,seat ez The development of the articulation index curve of the D13-IPS135 (in blue) compared with that of the competitor shows distinctly improved acoustic comfort throughout the operational range of the engine. The vibration produced by the Volvo Penta D13-IPS135 was almost always in the maximum comfort zone. Only at higher speeds did vertical vibrations increase. At low rpm the competitor suffered because of the expected behaviour of its V12 architecture. Forward facing propulsion with two counterrotating propellers gives greater efficiency than a conventional solution. Exhaust fumes are emitted through the transmissions in the wake of the propellers and conveyed behind the yacht for greater comfort. rpm of the Volvo Penta system. With all the obvious limits in terms of attainable speed and, obviously, of overall comfort at cruising speed. Finally vibration was measured. Here too the vibrations of the D13-ISP135, measured on three axes, had curves that were generally better than the V12 remaining, except for vertical shifts above 2 rpm, below the lines of excellent and good comfort. The competing engine behaved on average always worse remaining almost always above the optimum comfort line with vertical shifts starting at 14 rpm (but in any case always below the good comfort line up to 2 rpm) and a significant exit from the comfort zone for x-axis shifts between rpm. This was to be expected because of the V12 architecture that vibrates more at lower rpm. It s worth optimising The overall picture makes it clear that an optimised propulsion system expressly designed to guarantee comfort, easy driving and controlled running costs does indeed make it possible to compete with more powerful engines whose overall engineering is generically aimed at the marine sector but without having a clear target of reference. In this case the Volvo Penta D13-IPS135 demonstrated high level characteristics, effectively challenging propulsion units with higher power and capacity. This without considering the decidedly lower consumption with a positive difference of 78 L /h giving greater range and less atmospheric pollution. The other positive fundamental feature of the Volvo Penta propulsion system is the compactness that makes it possible to have more space available on board for other activities and an overall lower weight. The high level of comfort makes it possible to maintain higher standards in all conditions. An intelligent optimisation in which Volvo Penta has once again underlined the key values of its brand: comfort, safety and intelligent resource management. AB Volvo Penta Via Gallarate 182, 2151 Milan MI