The New 'energy DCi 130' Diesel Engine - A High-tech Package Derived From Renault’s F1 Experience

The 1.6-litre Energy dCi 130 is the world’s most powerful engine of its size, and therefore naturally best-in-class. Maximum power is 130hp, while peak torque is a generous 320Nm at 1,750rpm, some 80 per cent of which is available from 1,500rpm. In order to deliver real driving enjoyment in all situations, the newcomer boasts impressive performance and response worthy of larger capacity powerplants.

At the same time, its combined-cycle fuel consumption (NEDC) is 20 per cent better than the 1.9 dCi 130 engine it replaces, while CO2 emissions have been slashed by 30g/km. With the Renault Energy dCi 130 under the bonnet, Scénic and Grand Scénic will become the market's most frugal MPVs, with CO2 emissions of 115g/km and fuel consumption of 64.2 mpg, which extends their potential range on a full tank by 187 miles. They also qualify for the Renault eco² signature, the criteria for which have been stepped up recently.

In keeping with its tradition of innovation, Renault's objective was to bring its customers a core-range engine that durably delivered best-level CO2 emissions and fuel consumption without detracting from driving pleasure.

It is to this challenge that Renault's engine specialists rose in 2006 when they began designing this brand new engine. Working from a clean sheet of paper, the overriding aim was to produce a simple, efficient engine with innovation built into its genetic make-up. This decision meant that the engineering team was able to incorporate a range of advanced technologies from the outset to ensure a high standard of reliability. It also enabled fuel consumption and CO2 emissions to be slashed considerably. For the first time at this level, this engine incorporates six such CO2 technologies and saw Renault register no fewer than 30 patents.

This new block consequently marks the beginning of a new phase in Renault's engine downsizing policy. Some 75 per cent of the 264 components that have gone into the Energy dCi 130's are new, while most of the other 25 per cent come from the 2.0 dCi engine (M9R) which is widely acclaimed for its quality and reliability.

Eric Blanchard (Energy dCi 130 Project Leader): “Developing a new engine meant we were able to take advantage of the latest technological developments and also have a totally free rein with regard to design.

The Energy dCi 130 is also the fruit of collaboration between the engine specialists working out of Reuil and Viry-Chatillon

Thanks to the privileged ties they enjoy with Renault Sport F1, the engine specialists who work out of Rueil in France were able to profit from the expertise of Viry-Chatillon, also in France, to carry over a certain number of technologies developed and fine-tuned by their F1 colleagues to the world of production cars.

This technology transfer was facilitated by Philippe Coblence, the design office manager for the R9M project. Philippe formerly held the same position at Viry-Chatillon where he worked on Formula 1 engines at the beginning of the last decade. Three areas where F1 thinking was applied to the new Renault Energy dCi 130 engine are:

A 'square' architecture
The Energy dCi 130 engine has seen Renault innovate with the choice of a so-called 'square' architecture. The configuration of an engine is said to be square when the piston stroke is similar to the diameter of the cylinder (bore), an arrangement which allows large-diameter valves to be housed in the cylinder head for more efficient filling of the combustion chambers. This in turn favours performance. The concept is familiar in F1, where the quest for performance is so important, but it is still rarely employed for production diesel engines.3

Transverse water flow
This cooling technique, which is common in Formula 1, has been combined with a double water jacket design for the cylinder head. Transverse water flow, which is used in F1 to maximise cooling efficiency and minimise downforce losses, enables a smaller and therefore less energy-consuming water pump to be fitted. These two particularities have been exploited in the case of the Energy dCi 130 engine and have been combined with a double water jacket arrangement for the cylinder head. This feature permits the engine to benefit from a controlled rate of water flow to optimise cooling of the hot zones (combustion chamber, injector nozzles). Each cylinder benefits from identical cooling. Water is taken downstream of the water pump and does not flow round the combustion chambers. The system efficiently cools the cylinder head, enabling the engine's specific power output to be raised. Meanwhile, the water flows naturally through the system, which means that less energy is required to drive the water pump. This in turn results in less fuel consumption and CO2 emissions.

Work on internal friction

■Super-finishing and special surface treatments.
■UFLEX oil control ring technology, which has been used in F1 for more than 10 years, was incorporated from the very beginning of the project. The U-shaped geometry is highly flexible and enables the ring to adapt to bore distortion (under the effects temperature and pressure) in order to achieve the best compromise between efficiency (scraping of oil on the cylinder liner to reduce consumption) and friction. This technology necessitated extensive development work to optimise the ring's scraping action against the cylinder walls.
Philippe Coblence: The principle is comparable with that of a multi-blade razor. It adapts naturally to the contour without having to exert high pressure on the cylinder wall. The result is maximum efficiency and less friction.
Renault Sport F1: a high-tech laboratory which contributes to Renault's mechanical excellence
Nine world titles speak volumes for Renault's expertise in the realm of F1 engine development. For the 2011 world championship, no fewer than three teams have chosen Renault technology for their respective cars. So far, the results of the season's early Grands Prix are extremely encouraging: three wins for Renault power and eight podium places out of 12.

Bernard Rey (President, Renault Sport F1): “Formula 1 is a real asset for the brand: it builds awareness, serves as a test bed for new technologies and, above all, provides a global showcase for Renault's quality excellence. If you’re aiming to win in Formula 1, your engine needs to deliver total reliability and performance. There can be no compromise. Year after year, our multiple world titles in the sport – which is among the most demanding in the world – have demonstrated Renault’s expertise in terms of quality and mechanical excellence”.

An unprecedented technological package at this level of range
To reduce the engine's cubic capacity while maintaining a high level of performance, a number of technical solutions were explored in depth and selected at the design stage.

Maintaining outstanding performance

■Internal engine aerodynamics: work on the acoustics of the air intake ducts for optimal filling of the combustion chambers.
■Turbo technology: the low-inertia variable-geometry turbocharger ensures shorter response times from low revs (design, choice of materials, patented form of the blades). This technology gave rise to a Renault-registered patent.
■Swirl control: variable swirl technology optimises filling of the combustion chambers, while minimising polluting emissions at all loads and engine speeds.
■A lower compression ratio (15.4:1): minimises polluting emissions while maintaining a high level of performance thanks to a higher turbo pressure (2.7 bar, an increase of 12 percent over the engine it replaces).
■Injector technology: the design of the large combustion chamber bowl permits the use of seven-hole injectors for even greater combustion efficiency (injection over a large volume inside the combustion chamber).
■At the same time, capping the injection pressure at 1,600 bar (compared with 1,800 bar) has enabled the size of components to be reduced.
Saving grams of CO2/km
From the outset, the R9M engine was designed to be the best for low CO2 emissions. This implied designing an engine that would incorporate the latest technological knowledge at the time of its launch and which would be able to take onboard upcoming innovations throughout its development. This resulted in close collaboration between those working on the R9M project and their R&D engineering colleagues (Advanced Engineering and Innovation Department) at an advanced stage, with the latter permanently monitoring the availability of innovations in order to develop and propose them to the project team as and when they reached a sufficient degree of maturity.

Examples of this approach are the low-pressure EGR and the braking energy recovery system which were introduced in the course of the engine's development thanks to predispositions built-in from the very start.

This policy proved especially valuable as environmental awareness tipped from 2007 to make CO2 reductions a major strategic objective, a shift which allowed Renault's engine specialists to showcase their ability to adapt to changing circumstances.

As a consequence, the CO2 target fell from 140g/km in 2006 to 130g/km in 2007, and to 120g/km in 2009 for a 20g/km gain over a period of three years. This innovation-led approach allowed the project management team to constantly be in a position where it could respond to these new demands.

Work on reducing internal friction
Advanced work on the engine's internal friction brought valuable fuel consumption and CO2 emissions gains.

■Cold-running friction: the amount of time during which the engine runs cold has been reduced by three minutes thanks to a thermal management system which is described in detail (see Appendix 1 page 18).
■Hot-running friction: the choice of a shorter stroke allowed the dimensions of the rotating parts (crank assembly) to be optimised for less friction. The calibration of the piston rings and the surface treatment of the bearings (smooth thanks to high-precision machining: three passes instead of two) also contributed to reducing friction. This approach was founded on the Alliance's experience with the M9R engine (2.0 dCi).
■Reduced flow of fluids (oil/water): a double water jacket and transverse flow cylinder head cooling for enhanced efficiency (no elbows in the circuit). The flow of water is practically natural, making it possible to use a smaller water pump requiring less energy.
The introduction of new technologies
The Energy dCi 130 packs a raft of CO2 technologies which are unprecedented at this level of range.

■A carefully-developed Stop&Start system combined with deceleration/braking energy recovery.
■Cold-loop, low-pressure exhaust gas recirculation (EGR). Renault is the first manufacturer to introduce this technology in Europe.
■Thermal management technology.
■Variable displacement oil pump.
■Variable swirl technology.
■A multi-injection system designed to optimise regeneration of the particulate filter (DPF).
CO2 gains* associated with the different technologies employed

TECHNOLOGY Estimated CO2 saving
Downsizing 5.5%
Transmission ratios 3%
Stop&Start 3%
Recovery of deceleration/braking energy 3%
Low-pressure EGR 3%
Thermal management 1%
Variable displacement oil pump 1%
Variable swirl 0.5%
TOTAL 20%

(*) compared with the 1.9 dCi engine (F9Q)

For further information concerning the technologies employed for the Renault Energy dCi 130 engine, see Appendix 1 (page 14).

Carefully-tuned acoustics
At the same time, considerable attention was paid to the new engine's acoustic performance thanks to advanced work on combustion in order to deal with noise -generation at source. For this, Renault's engine specialists called extensively on input from the company's NVH department (Noise, Vibration, Harshness), based at the company's Technical Centre in Lardy, France, which permits the acoustics of an engine to be finely tuned.

Gilles Nghiem (acoustics specialist): The range of acoustical tests we carried out on the Energy dCi 130 engine enabled us to guarantee vibratory reliability and minimise noise generation without having to resort to encapsulation, since noise was dealt with at source. Scénic’s acoustic performance with this powerplant is worthy of a D-segment vehicle, while exterior noise does not exceed 72 decibels, a threshold championed by the Golden Decibel.

Renault's NVH department (Noise, Vibration, Harshness) is based in Lardy, France, and provides the company with an advanced tool when it comes to fine-tuning the development of new engines and optimising their acoustic performance. It was inaugurated in 2005 with €25 million investment. In addition to its cutting edge development tools, the department employs a team of approximately 60. The Energy dCi 130 is the first engine to have benefited fully from this expertise from the very outset of the project.

The department's work naturally covered the new engine's acoustics, which involved minimising noise generation and fine-tuning its pitch. Its acoustical engineers also contributed extensively to the quality and reliability of the new powerplant, and the work of the NVH Department included dialling vibratory reliability into the new engine's DNA.

Renault – the Alliance’s diesel expert
Recognised as the diesel specialist within the Alliance, Renault led the engine's development throughout the project which was co-funded by Nissan.

Renault's Energy dCi 130 engine is the fourth diesel engine to be developed within the framework of the Alliance, following the 2.0 dCi (M9R), 3.0 dCi (V9X) and 2.3 dCi (M9T) powerplants.

The R9M project is of key importance for the Alliance, since it represents large volumes in Europe for both brands:

■Renault: Scénic and Grand Scénic, then the complete Mégane range
■Nissan: some C-segment models
■Capital outlay synergies:
■Less costs involving the adaptation of vehicles thanks to similar architectures (Scénic and Qashqai share the same platform).
■The project benefited from Nissan's production quality expertise and its experience with the 2.0 dCi engine (M9R), the advantage being strong process capability* from launch.
(*) Process capability: the ability to produce 100 percent conform parts with little dispersion.

Key figures

Renault Energy dCi 130
Investment €230 million
Project duration 32 months
Number of components 264 (76 per cent new)
Staff mobilised 160 engineers and technicians
Bench testing 15,000 hours**
Track testing 700,000 km


** These tests done in extreme conditions simulate a whole life cycle for the engine i.e. 300 000 km or 20 years

Renault Energy 1.6 dCi 130 engine - Technical Data

Engine family (Renault) R9M
Cubic capacity (cc) 1,598
Bore x stroke (mm) 80 x 79.5
Number of cylinders / valves 4 / 16
Compression ratio 15.4:1
Maximum power 96kW (130hp) at 4,000rpm
Maximum torque 320Nm from 1,750rpm
Fuel injection Common rail
Depollution standard Euro5
Gearbox Six-speed manual (ND4)
First use in the range Scénic and Grand Scénic, then extended to the entire Mégane range
Combined-cycle fuel consumption * 64.2 mpg
CO2 emissions* 115g/km

* Scénic and Grand Scénic