Research On Heavy-duty Dump Truck Fuel Economy Based On Using Condition

This dissertation was carried out by workgroup of"Fuel consumption reduction for heavy-duty vehicle", combined with the project of "Fuel consumption reduction for heavy-duty vehicle series based on user working conditions". Based on the survey result of heavy-duty dump truck users, and the analysis of a large number of experimental data, engine operation duty cycle was built by the use of principal component analysis and cluster analysis of different road conditions. Meanwhile, engine load distribution under different road and load conditions was obtained by statistical analysis using interval statistics. Engine duty cycle was built base on user operation conditions.The heavy-duty dump truck model was established by CRUISE simulation software. Based on the validation of model accuracy, the integrity of travelling cycle and engine duty cycle was verified, and further demonstrated that the whole vehicle duty cycle represented the actual engine load distribution, and the whole duty cycle can be the correct guidance of vehicle fuel economy evaluation and power train matching. According to the engine cycle, aimed at small and medium engine speed region of the commonly used working condition, with the goal of lowest fuel consumption.The engine bench test of optimized calibration and multi-condition fuel consumption test of real vehicle chassis dynamometer based on vehicle driving cycle, are proved that the study of fuel economy research of heavy-duty dump truck are effective and significant.The main contents of the dissertation are as follows:1. Establishment of heavy-duty dump truck driving cycleBased on the analysis of users'operation status of heavy-duty dump truck, it was found that the road condition, load status of heavy-duty dump truck has characteristic of stability and strong regularity. Heavy-duty dump truck as a result of its own structure and use of other reasons decided to operation condition of its complexity. In accordance with generally one-way heavy-duty dump truck load and road conditions in the mileage of the proportion of heavy truck traffic on the cycle of the user test is subdivided into cross-country roads, general roads and good roads in general. On the basis of analysis on user test methods, measured parameters and driving characteristic parameters, the dissertation focused on the establishment of vehicle driving cycle which are applied by principal component analysis and cluster analysis, and verified the effectiveness of established cycle. User based vehicle driving cycle is in line with the heavy-duty dump truck of actual status and closed to user practical work form.2. Establishment of engine operation cycleUsing interval statistics method, engine load distribution under different load conditions are proposed,Statistics from the distribution of engine load results in cross-country road traffic on the engine speed under low-speed zone, the engine load on the small and medium-sized load area; general road traffic distribution under the engine speed is sparse and scattered throughout the engine speed range with the use of the probability distribution of the load than Average; good road traffic engine speed under the high concentration zone in the middle-and high-speed. and engine working cycle based on user operation status which is applied by statiscics theory, is established. The engine working cycle is in line with the actual use status. By comparision with the ESC steady-state cycle, it was found that the actual operating conditions are so different to the ESC standard test cycle. If using GB standard test cycle to guide the engine design and optimization, it will inevitably lead to the actual requirements are not suitable. At the same time, it was found that the frequency of gear shift had relationship with not only dump truck load, but also road conditions to great extend. Shift the use of vehicles to some extent on the probability distribution reflects the quality of traffic and vehicle traffic load status.3. Establishment of vehicle model based on CRUISE softwareThe heavy-duty dump truck model was established by CRUISE simulation software. Based on the validation of model accuracy, the integrity of travelling cycle and engine duty cycle was verified, and further demonstrated that the whole vehicle duty cycle represented the actual engine load distribution, and the whole duty cycle can be the correct guidance of vehicle fuel economy evaluation and power train matching.4. Engine re-optimization based on commonly used operating conditionsAccording to the engine cycle, aimed at small and medium engine speed region of the commonly used working condition, with the goal of lowest fuel consumption, CAMEO automatic calibration system was applied to realize the automatic optimization calibration of CA6DL1-28 diesel engine of heavy-duty dump truck. After the optimization calibration of the specific operating conditions of diesel engine, the fuel consumption ratio of CA6DL1-28 diesel engine in low-speed area was lowered by about 2~7g / (kW·h), which achieved the optimization purpose.5. Validation test of fuel economy based on chassis dynamometerBased on fuel economy test through chassis dynamometer, it was proved that the study of fuel economy research of heavy-duty dump truck is effective and significant, and had reach the desired goal. So the study of engine commonly used region based on user operation conditions is of great significance.