HL130
- Type: Diesel engine
- Length: 1,490 mm
- Width: 1,010 mm
- Height: 800 mm
- Dry Weight: 1,420 kg
- Bore/stroke: 110/115 mm
- Displacement, cylinder: 1.1 l
- Displacement, total: 13.20 l
- Compression ratio: 15.5:1
- Charging method: Variable-geometry two-stage turbocharger
- Intercooling: Air-oil intercooler & aftercooler
- Number of Cylinders: 12, V, 90 degrees
- Cooling method: Oil cooled
- Injection method: Common rail, direct injection @ 270 MPa
- Specific fuel consumption: 180 g/kW-hr
- Power: 1,200 kW (1,600 PS) @ 3,200 RPM
- Torque: 4,500 N-m @ 2,100 RPM
- Fuel: F-54/DF-2, F-34, F-24
Overview:
The AMG HL130 is an advanced oil-cooled, low heat rejection (LHR), turbocompound V12 diesel engine intended for military ground vehicle propulsion and onboard power generation applications.
Design & Construction:
The erngine crankcase is a one-piece compacted graphite iron casting (GJV-450:, minimum 450 MPa tensile, 70–80% nodularity CGI) with a deep skirt extending 60 mm below crank centerline and an integral cast ladder frame closing the bottom structure. CGI is used over gray iron for a 75% fatigue strength advantage and over aluminum for thread holding and bore stability at the high per-cylinder gas load. Main bearing caps are constructed forged steel cross bolted through the skirt. As there are no conventional water cooling jackets the block casting consists of the bore columns, bulkheads, cam gallery, and oil transfer drillings only. Core count is reduced by half relative to a we -jacket block of equal rating and the closed sections between bores raise block torsional stiffness approximately 20% at 8% less mass than a water-cooled CGI equivalent. Machined features include the liner counterbore and mid band pilot; the annular liner cooling gallery feed drillings, main oil rifle, piston cooling jet rifle, and the head stud bosses. Crankshafts are forged from 38MnVS6 vanadium microalloyed steel. Rods are forged 36MnVS4. A rifle drilling up the shank feeds pressure oil from the bi -end groove to the pin bushing. Small end is trapezoidal to spread the compressive gas load over the full pin boss while clearing the piston underside oil gallery; the bushing is a rolled C63000 aluminum bronze shell with a sputtered overlay. All crank bearings are of hydrodynamic sleeve type. Main shells are bimetal on the upper and tri-metal on the lower; rod shells are steel backed leaded bronze substitutes (lead-free CuSn10Bi3) with a sputtered AlSn20 overlay and polymer running in layer. Camshaft bearings are direct bored in the head with sputter coated steel shells, the turbocompound gear train and PMSG use rolling element bearings.
The timing gear train is carried at the rear flywheel en) to place the gear mesh at the node of the crank torsional mode and minimize cam drive torsional excitation. Gears are shot-peened, ground 18CrNiMo7-6 with 22 µm profile crown. The train drives, in order: camshaft(s) (0.5:1), high-pressure fuel pump (1.4:1, delivering 3 pumping events per cylinder firing), variable-displacement oil pump, and the turbocompound output mesh. The accessory drive is entirely gear and electric: no belts. Fuel transfer, oil scavenge (for the 40% side-slope requirement, twin scavenge sections in the pan corners), fuel priming, and air compressor loads run from the gear train; all other accessories (fans, hydraulic pumps, HVAC) are vehicle electric loads served by the PMSG. The structural oil pan is a salt-core aluminum MMC casting (15 vol% SiC particulate) contributing to powertrain bending stiffness. Sump capacity is 1.9 L per rated liter of displacement (25 L for the 12V) with baffled pickup, twin corner scavenge pumps, and a deaeration tank cast into the flywheel housing top, qualifying the lube system for 60% grade and 40% side slope continuous operation.
Piston & Cylinder System:
The cylinder liner is centrifugally cast CGI, top-flange supported, wet only over a 25 mm annular cooling band at top ring reversal (TRR) and dry-fitted below. The flange is clamped between the block counterbore and the head insert sealing land, carrying the fire seal on a raised steel-ring gasket land. The TRR cooling band is an annular gallery formed between two O-ring-sealed pilot diameters fed by four tangential drillings from the block gallery at 3.5 L/min per cylinder. Oil enters tangentially to establish swirl, holding the TRR bore surface at ≤320 °C at rated conditions. Below the band the liner runs intentionally hot (mid-stroke bore ~260 °C), reducing ring-zone friction 12% versus a fully cooled liner and eliminating cold corrosion regimes on high sulfur diesel fuels.
Bore surface employ a 90 µm plasma-sprayed amorphous chromium carbide ceramic wear coating, diamond-honed to a plateau finish of Rk 0.25 / Rpk 0.08 / Rvk 0.60 µm with 55° cross-hatch. The piston is a three-piece articulated design with a steel crown, MMC skirt, and full-floating pin. The crown is closed-die forged 42CrMo4+Nb steel made in two halves, friction-welded at the ring land and gallery walls to form a sealed dead-air insulation gap beneath the combustion bowl and a closed cocktail-shaker oil gallery behind the ring belt. The combustion face carries a 2.0 mm thermal barrier consisting of a 0.15 mm NiCrAlY bond coat, 1.1 mm graded YSZ/metal zone, 0.75 mm gadolinium zirconate top layer applied by air plasma spray and finish-machined to bowl profile. The combustion bowl is a shallow re-entrant torus sized to the 148° injector cone. Crown metal maximum temperature is 480 °C beneath the TBC, top ring groove temperature is 330 °C at rated. 70 °C below the 400 °C deposit-control limit of the lubricant. The top ring groove is induction-hardened and the second groove machined in the parent forging. The skirt is squeeze-cast AlSi12CuNiMg with 20 vol% Saffil (Al₂O₃ short fiber) selective reinforcement in the pin bosses and skirt panels, raising panel stiffness 40% and 300 °C yield strength 60% over the unreinforced alloy. Skirt faces carry a 20 µm graphite/PEEK screen-printed coating. Pin is 18CrNiMo7-6 case-carburized, DLC coated, full-floating with pressure lubrication from the rod rifle; bore is tri-arc profiled to relieve edge loading under the gas load. Rings are a three-ring pack with a top ring 3.0 mm keystone (15°), gas-nitrided steel with 250 µm HVOF CrC-NiCr cermet face, barrel-lapped. The second ring is a 2.5 mm rectangular napier, chromium-ceramic face; oil ring 3.0 mm two-piece with coil expander, with chromium-ceramic rails. Piston cooling is a fixed jet per cylinder (4.5 L/min at rated pressure) feeding the cocktail-shaker gallery via a catcher funnel in the skirt; gallery-out oil temperature at rated is 205 °C, within lubricant capability. Each cylinder's combustion deck is a replaceable insert module consisting of a gas-pressure-sintered silicon nitride (Si₃N₄) disc carrying the flat combustion face, both valve seat pairs (seat faces finish-ground directly into the ceramic at 30°/45° two-angle geometry), the injector nozzle bore with its thermal sleeve, and the liner fire seal land. The gas face carries a 0.3 mm zirconia washcoat trimming deck heat rejection to the 550 W budget. The insert seats in a counterbored pocket in the CGI head on a 0.5 mm compliant Ni-alloy corrugated gasket ring that accommodates the ceramic/iron expansion mismatch while sealing combustion gas at 25 MPa. Retention is by the head clamp load path with a shrink band Inconel hoop around the insert OD providing compressive prestress (−180 MPa hoop at assembly) that keeps the ceramic in net compression at all operating states. The module is field replaceable with the head on the engine.
Cylinder heads are GJV-450 CGI, one per V bank. With the combustion face carried by the ceramic inserts the iron structure performs clamping, porting, and valvetrain support and contains no coolant. The only liquid circuits in the head are three selective cooling drillings per cylinder consisting of the valve guide boss loop, injector sleeve loop, and a bridge drilling between exhaust seats carrying a combined 2.5 L/min per cylinder of lubricant, sized to hold guide bosses ≤ 240 °C and the injector tip ≤ 200 °C, the injector itself also being fuel-cooled). Intake ports are uninsulated high-swirl (swirl ratio 1.4) Siamese-fed from the inter-bank module; exhaust ports carry cast-in-place IN625 double-wall air-gap liners hat hold port heat rejection to 800 W/cylinder and deliver exhaust to the manifold flange within 25 °C of exhaust valve outlet temperature. Four valves per cylinder in a parallel-valve flat-deck arrangement , required by the ceramic insert geometry and favorable for the shallow-bowl combustion system).γ-TiAl (Ti-48Al-2Cr-2Nb) intake valves cut reciprocating valvetrain mass 45%, permitting single ovate-wire springs at 3,200 rpm with 1.35 dynamic margin. Guides are centrifugally cast bronze-matrix with solid lubricant dispersoid, run against the selective cooled bosses. One overhead camshaft per bank gear-driven, runs in seven bearings direct in the head. Valves are actuated by roller finger followers (needle-roller, DLC pivot pads) with high-temperature-rated hydraulic lash adjusters. Cam torsionals are controlled by the rear gear train location.
Air system:
The gas path is air cleaner to LP compressor to air-to-air intercooler to HP compressor to air-to-air aftercooler to intake manifold to cylinders to exhaust manifold to HP turbine (with proportional bypass) to LP turbine to turbocompound power turbine to exhaust. The compressors, coolers' charge ducting, and manifold form the inter-bank module. Overall compressor pressure ratio is 4.8:1, split nearly evenly between stages so that each stage operates at a ratio where centrifugal stage efficiency peaks. Ccombined turbocharger total-to-total efficiency (compressor × turbine × mechanical) is 78% at the design point and ≥ 75% over the upper half of the load/speed map. The single stage LP compressor is constructed from a single titanium billet with backswept 38° blades and a vaneless diffuser. The corresponding LP turbine is a dual alloy radial (MarM247 wheel / IN713 shaft) with a 72,000 rpm design rotor speed. HP compressor is a another single titanium billet is a dual-alloy radial, twin-scroll (pulse-divided per firing group) with a 98,000 rpm design rotor speed. Bearings are gfull-floating angular-contact ceramic ball, squeeze-film damped, engine-oil fed with dedicated 90 °C-limited cooled branch. Three actuators control the gas path with a proportional HP-turbine bypass valve that shifts expansion work to the LP stage as flow rises, keeping the small HP stage matched for low-speed boost without overspeeding at rated, the power turbine variable nozzle, and a compressor recirculation valve on the HP stage for surge protection during load rejection. There is no wastegate to ambient, all bypassed energy remains available to downstream stages. Boost scheduling at peak torque (2,100 rpm) is the HP bypass is closed, the power turbine nozzle opened to its transient stop, and the small HP stage delivers PR 2.6 alone against LP PR 1.6, sustaining 3.36 MPa BMEP with trapped A/F ≥ 27:1. Load response from 10% to 90% torque at 2,100 rpm is 0.9 s to 90% of demand, achieved by (a) the twin-scroll HP stage and its low inertia ball-bearing rotor, power turbine nozzle dump , and PMSG boost assist injecting up to the machine rating at the crankshaft while boost builds , the combination eliminating the smoke limited fueling window entirely, and the ECU's smoke limiter operates as a monitor rather than a scheduler. The two-stage system holds full rated A/F to 2,500 m by bypass/nozzle rescheduling within compressor speed limits; from 2,500 to 4,000 m fueling derates linearly to −10%. At 50 °C ambient, cooler effectiveness reserves hold intake manifold temperature ≤ 95 °C at full rating. Intercooler and aftercooler are bar-and-plate air-to-air cores integrated with the lube-oil cooler into the vehicle heat exchanger group, fed by electric fans powered from the PMSG bus (fan power is thereby load-scheduled, not shaft-locked). Core face velocities and fin densities are set for a 50 °C day with 15% fouling reserve. The intercooler drops LP compressor discharge air from 121 °C to 63 °C before the HP stage, reducing HP compression work ~11% and holding HP discharge to 152 °C, protecting the aftercooler and manifold seals. The intercooler is charge-side-integrated into the engine's inter-bank module with short, equal-length ducting while its core is physically located in the vehicle cooling group and connected by twin silicone free metallic bellows ducts. On humid days the intercooler outlet can pass below dewpoint at part boost where the 2-pass down-flow charge circuit drains condensate to a low-point trap with a float purge valve venting to the exhaust ejector. Charge-side cleanliness is protected by the engine air cleaner (99.9% at 5 µm, cyclonic + barrier), air-side (cooling airstream) fouling provisions are handled at cooling group level.
The turbocompound stage expands exhaust gas leaving the LP turbine through a single stage axial power turbine and returns the recovered work to the crankshaft through a fixed ratio gear train and viscous coupling. Recovered shaft power at rated conditions is approximately 5.5% of crankshaft power. Beyond its SFC contribution the stage lowers final exhaust gas temperature by 60 to 80 °C at high load relative to a non-compounded LHR engine and provides 15 to 20% additional slowing power in braking mode. The power turbine is a single-stage axial turbine, 50% reaction at the mean line, expansion ratio 1.90 at rated, with a total-to-static efficiency 84% at the design point. The turbine is an integrally bladed MarM247 casting with a 14-vane variable nozzle with cooled trunnions having a 35 to 110% area range. Bearings are ceramic hybrid ball pair, squeeze-film damped, with a full 120° tri-hub burst containment ring. Design rotor speed at rated power is 52,000 RPM. The variable nozzle is the primary controller of the exhaust manifold to boost pressure ratio. At rated load the nozzle holds backpressure/boost at 1.25, above unity, so pumping work is negative. At part load and during accelerations the nozzle opens toward its 110% stop collapsing backpressure to ≤ 1.05 × boost so the turbine freewheels near zero torque and transient response is unimpeded. In braking mode the nozzle closes to 35% area with fueling cut, the engine pumps against the throttled turbine, and the turbine's recovered work is absorbed as additional retardation through the gear train, raising total engine braking to 520 kW at 3,200 rpm without an exhaust brake valve. Turbine-to-crankshaft gear ratio is 16.25:1, taken in two ground helical stages (4.60:1 then 3.53:1) hard-mounted in the rear gear case with a viscous silicone-shear isolation coupling between the second stage and the crank gear mesh. The coupling isolates the turbine rotor from crankshaft torsional velocity ripple, slips during backfire/surge events limiting torque to 1.8 × rated recovery torque, and accommodates the speed mismatch during nozzle-dump transients. Gear stages are 18CrNiMo7-6, ground DIN 3 quality, superfinished, with tooth bending and pitting lives computed to 25,000 hr at the 90th-percentile mission profile, the gear train is a life-of-engine, non-serviced assembly. Recovery train mechanical efficiency is 96.5% turbine-to-crank.
Fuel & Combustion System:
Fuel injection is common rail at 270 MPa with twin gear-driven three-plunger radial pumps, a forged rail per bank with flow-limiter fittings, and piezo-servo injector. Up to five events per cycle are scheduled: two pilots (noise and rate-of-rise control, dP/dθ limited to 1.0 MPa/deg), main, and up to two posts (smoke and exhaust-temperature management). Closed-loop control uses in-cylinder pressure sensors (one per cylinder, glow-plug-position piezoresistive) governing 50%-burn location to ±0.5° and balancing cylinder-to-cylinder PCP to ±0.8 MPa.F uel type is inferred from rail pressure-decay viscosity sensing and injector closing-response signatures; maps for density, bulk modulus, and lubricity class are selected automatically. JP/F-34 hardening comprises DLC-coated needles and control valves, WC-coated pump plungers and tappet rollers, and rail-pressure derate scheduling that holds injector internal leakage within limits at kerosene viscosity; power derate on F-34 at 52 °C is 4%. Fuel cooling of the injector body is by return-flow routing (0.4 L/min per injector).
Lubrication & Cooling System:
The engine lubrication system is a dry-deck, wet-sump design with priority-valve architecture. Flow path is sump to suction screen (twin pickups) to two-stage variable-displacement vane pump to duplex full-flow filtration to oil-to-air cooler with proportional bypass to thermostat-blended main gallery to distribution. A separate low temperature branch serves the turbomachinery and PMSG. Scavenge is by two gear type corner pumps returning to the deaeration tank cast into the flywheel housing. The oil pump is a two-stage variable-displacement vane pump crank gear driven at 1.15:1 mounted on the ladder frame with direct sump suction. Stage one is 145 cm³/rev maximum displacement, swash-controlled from 30% to 100% by an ECU driven proportional pilot valve delivering the 500 kPa main gallery against a pressure flow schedule commanded by the ECU (map of speed, load, and oil temperature)rather than a fixed relief setting. Second stage (jet/cooling) is a 60 cm³/rev fixed-displacement section feeding the unregulated piston-jet branch so jet flow rises with engine speed exactly as piston heat load does independent of main gallery scheduling. Cold-start relief at 900 kP is provided by anti-drainback check valves that hold the filter module and gallery primed; pre-lube is by PMSG slow-roll. Filtration and contamination control is provided by a duplex full-flow spin-on module. A 5% partial-flow centrifugal separator (oil-pressure-driven, 55,000 g) controls soot and sub-micron wear debris. Magnetic drain and chip detectors at both scavenge returns and the recovery gear case, wired to the health monitor.
Gallery feed temperature is regulated at 110 to 120 °C by a proportional ECU-driven bypass valve blending around the oil-to-air cooler. Warm-up is full bypass, additionally the turbocompound nozzle is partially closed and PMSG generating load applied to accelerate heat input, bringing oil from 25 °C to 90 °C in under 6 minutes at fast idle. The insulated combustion chamber reaches stable surface temperature in under 2 minutes, decoupling combustion-quality warm-up from oil warm-up. Normal operation feed is regulated to 115 °C ± 5; sump stabilizes near 128 °C; cooler inlet 138 °C at rated. Overtemp governance is staged response at 132/138/145 °C feed with fan step-up, PMSG load shed, torque derate before any hard limit. Turbocharger ball bearings, the power-turbine bearing cartridge, and the PMSG stator jacket require feed below the 110–120 °C main gallery level . A dedicated branch taps upstream of the thermostat blend, passes through its own small plate-type oil-to-air core integral to the main oil cooler assembly and is regulated to 85 to 90 °C. Post-shutdown an electric 24 V circulation pump (0.9 kW) runs this branch for up to 4 minutes on turbo/power-turbine soak-back, powered from vehicle batteries. Structural MMC pan a with 25 L capacity and full-length baffle deck with reed-valve drainbacks, and twin gerotor scavenge sections in the pan corners. All returns pass the flywheel-housing de-aeration tank with tangential-entry cyclonic separation plus a coalescing screen holding gallery aeration ≤ 4% at rated speed and 40% side slope. Qualified attitude envelope is 60% grade and 40% side slope continuous, 100%/60% for 60 s, inverted survival (fuel-cut) 10 s. For fording the pan, filter module, and breather (labyrinth + centrifugal, closed-circuit to intake) are qualified for 1.5 m submersion. The lubricant is a single high-temperature synthetic lubricant (polyol-ester/PAO base, HTHS 3.7 mPa·s, qualified to 340 °C sustained ring-zone exposure, 400 °C to -ring-groove deposit limit, 500 hr / 25,000 mi drain) and performs all lubrication, all hydraulics (lash adjusters, coupling fill), and all liquid side cooling. At −40 °C the lubricant remains pumpable. Start sequence is PMSG slow-roll at 60 rpm for 5 s establishes film in mains and lifts gallery pressure ≥ 80 kPa (pre-lube), then crank to 400 rpm with intake grid heating. An arctic kit adds a 3 kW battery slave sump heater blanket and inverter fed stator jacket reverse heating with the PMSG as a resistive heater at standstill.
The cooling system is designed to reject 450 kW (50 °C day, full rating) within an armored volume budget of ≤ 0.45 m³ including fans, plenums, and armored grille with electric drive, degraded mode capability, and signature management. The design is a two-fan annular-core module with cooling cores arranged as a rectangular ring or radiator box")around two axial entry, radial-discharge mixed flow fans, so that air enters through roof or deck grilles, passes once through the cores, and is discharged by the fans through directable exhaust grilles. The concept eliminates the plenum dead volume of conventional fla -radiator/axial-fan stacks and lets the fans work against the core resistance with near uniform face velocity. The four cores (aftercooler, intercooler, 2 × oil cooler) form the four walls of a box 700 × 700 × 460 mm around the fan pair; inlet grilles feed the outside faces, fans scavenge the inside and discharge axially through the module end. Two identical mixed flow (meridional exit angle 45°) fans selected over pure axial for their steep pressure capability at compact diameter and tolerance of non-uniform inlet flow behind armored grilles. Each fan includes 11 blades plus a 13-vane diffuser cascade with blades constructed from carbon-fiber PEEK injection-molded blades on forged Al hub with individual blade replaceability. Electrical fan power at the 50 °C full-rating corner is 70 kW (both fans) from the PMSG bus. Because drive is electric and fully variable fan power tracks the actual heat load rather than shaft speed. at tactical cruise on a 25 °C day the group runs one fan at 40% speed. The ECU thermal manager schedules fan speed from a multi-input observer (oil feed temp, charge cooler outlet temps, ambient, load forecast from the driver demand signal) with feedforward on load steps so airflow leads heat arrival. Inlet and outlet grilles are chevron-baffle armored louvers with the pressure budget of 0.9 kPa total held by oversizing louver free area 2.3× core face area. Grille frames carry quick-release fasteners for core access, outlet grilles are directable (±15° vane sets) so exhaust cooling air can be biased away from crew positions and thermal-sensor aspects and can optionally be ducted to mix with engine exhaust in an ejector shroud for IR plume dilution. Louver fin geometry is dust-shedding and the reverse purge function handles field accumulation with full wash access through the grille frames. All cores are chromate free conversion-coated and topcoated for salt-fog, sand erosion of leading fin edges is met with 0.4 mm parting sheet margins and a sacrificial pre-screen at the inlet grilles. Vibration/shock qualification id 25 g shock, tracked-vehicle PSD endurance at module level with cores on wire-rope isolators inside the armored frame. The module reserves a fifth, thin core position (620 × 300 × 40 mm) for vehicle loads including transmission/final-drive oil in mechanical installations, or traction-generator/inverter coolant in series-electric installations (up to 45 kW at 65 °C loop temperature).
Starter/Generator:
The engine carries a PMSG between the last main bearing and the output face consisting of a a 32-pole Sm₂Co₁₇ surface-magnet (Sm₂Co₁₇, selected over NdFeB for 220 °C thermal robustness) rotor mounted on the crankshaft flange in place of a conventional flywheel with an oil-jacketed stator carried in the flywheel housing and a 700 VDC SiC inverter mounted on-engine. On the 12V engine the PMSG is rated at 240 kW peak (30 s) and 160 kW continuous. PMSG functions include engine cranking (−40 °C start from vehicle battery, spin to 400 rpm with intake heating; no separate starter motor), silent watch export power at low idle, transient boost assist, active damping of driveline torsionals via inverter torque modulation, replacing elastomeric couplings, and stationary export power at the continuous rating. The base engine is designed and qualified for two downstream load cases with no change to engine hardware. For mechanical drives the PMSG rotor hub carries a standard flexplate/damper-plate pilot for automatic and cross drive transmissions. Torsional compatibility is delivered by the PMSG active damping function plus a transmission specific damper plate; the qualification envelope covers lock up driveline modes from 1.2 to 8 Hz and torque reversals to −40% of rated. For series-electric drives the same housing and hub accept a close-coupled traction generator cartridge, a customer furnished or program standard PM generator sized to the engine rating spigoted on the housing bore and splined to the PMSG hub. For this case the engine governor operates in speed-band/power-follower mode against the DC bus controller, the PMSG supplements the traction generator during bus transients and the turbocompound stage continues to feed the crankshaft mechanically. Output-end structural qualification covers the generator cartridge overhung mass and its short-circuit fault torque which sizes the hub spline and the last main bearing web on each model.
Engine Control:
A dual-channel engine control unit executes closed-loop combustion control from per-cylinder pressure sensing (CA50 phasing, PCP limiting/balancing, knock-integral monitoring on kerosene fuels), rail pressure and multi-event injection scheduling with multi-fuel adaptation, gas path control of the HP bypass, power-turbine nozzle, and recirculation valve from a physics based airpath observer, thermal management of oil temperature, cooler bypass, and electric fan commands, PMSG torque coordination (crank, assist, damp, generate) via CAN-FD to the inverter, and health monitoring (oil condition, turbo speed/vibration, blowby flow, insert-face thermocouple rakes on qualification engines). The governor presents both a torque-based mechanical-drive interface and a power/speed-band series-electric interface to the vehicle bus controller. Control hardware is qualified to relevant military environmental and EMI standards, software is partitioned so the combustion, airpath, and output-coordination functions are model common.