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Hybrid bulldozers use less fuel by providing better efficiency and fewer emissions, which was confirmed by one Caterpillar application of D7E in the market in 2010. To take advantages of the series hybrid bulldozer system, Chinese government launched similar hybrid bulldozer with independent double motor design. The Hybrid Bulldozer Power-Train system includes 14 components including motor, motor control system, engine, super capacitor to BMS and etc. This specific hybrid architecture, compared with D7E, removes the complicated hydraulic steering system. Instead, the steering function was developed by running both traction motors, further simplifying the power-train system. A Diesel engine is used to propel the attached generator to produce AC power which is then converted to DC power and connected with the main power link (super capacitor). DC power is finally converted back to AC to propel those two independent traction motors. CAN network is applied for communication.

The introduction of stringent EPA 2015 regulations for locomotive / marine engines and IMO 2016 Tier III marine engines initiates the need to develop large diesel engine aftertreatment systems to drastically reduce emissions such as SOx, PM, NOx, unburned HC and CO. In essence, the aftertreatment systems must satisfy a comprehensive set of performance criteria with respect to back pressure, emission reduction efficiency, mixing, urea deposits, packaging, durability, cost and others. For on-road and off-road vehicles, urea-based SCR has been the mainstream technology to reduce NOx emissions. For category II marine engines with single cylinder displacement volumes between 7 liters and 30 liters, IMO III (Tier IV) emission regulations dictate approximately 80% reduction of NOx emissions vs. Tier II emission regulations [1]. Urea / ammonia SCR is being considered as an enabling technology to achieve IMO III regulations without significant impacts on engine performance and fuel economy.

Flame spread over a melting thermally thick composite polymer is investigated in a channel flow above a condensed fuel. The condensed fuel consists of an isotropic (melted layer of) liquid near the heated surface and an anisotropic (not-yet-melted) solid surrounding it. The influence of the solid anisotropy is evaluated by changing the solid conductivity (ksx or ksy) in one particular direction (x in horizontal flame spread direction or y in vertical direction, see schematics in Figure 1) while keeping the other properties fixed. Note that the liquid conductivity kl has no isotropic behavior. Numerically, it is found that the flame spread rate decreases with either increasing ksx or ksy. The decrease with respect to ksy is less than for a comparable case described by the de Ris formula for an isotropic pure solid. The flame spread rate is more accurately determined by an analytical formula derived for spread across a melting solid fuel.

Refuse trucks are used in many communities for garbage collection and compression in China. This article introduces representative driving cycles of refuse trucks in multiple cities. System configuration is described first. Then, traditional pedal map, shift-pattern, and shift-point are used as basis to optimize energy utilization for specific hybrid configurations under refuse truck driving situation. Since AC power is used as source for garbage compression, to take advantage of such operating characteristics, engine start and stop technology can be a viable technology to improve fuel economy. Experiments are conducted to reach the conclusions.