Impact Analysis of the Aging Silicone Oil in the Damper on the Torsional Vibration of the Crankshaft of the Heavy-Duty Vehicle Diesel Engine

Torsional vibration is one of the major issues and very important calculation for the safe running of heavy-duty diesel engines, specifically crankshaft. Because of different applications of a heavy-duty diesel engine, different driven machine and different attaching systems are inevitable that affect the torsional system. The cranktrain contains the flywheel and torsional damper. The properties of these parts have significant effect on torsional vibration of the system as well as the crankshaft strength. Initial selection of these properties is usually specified based on engine designer experience and also the torsional vibration calculation of the cranktrain. In this paper, the focus is to find the optimum and reliable operating points for the elements in cranktrain using computer-aided engineering (CAE) tools. These are parameters like tuned mass inertia, flywheel inertia, damper stiffness, damper inertia, damper damping, coupling damping and coupling stiffness. The effect of these parameters on system design criteria, especially crankshaft life, was investigated. The results show high sensitivity of crankshaft safety factor to parameters like tuned mass inertia, damper damping coefficient and damper stiffness. Therefore, damper selection is the most important factor to increase the crankshaft life. The new contribution is that the parameters related to the whole cranktrain system that have the greatest effect were obtained and an optimisation was executed on these parameters to fulfil the vibration targets as well crankshaft life.

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Tests and Numerical Simulations on the Thermal Load of the Cylinder Head in Heavy-Duty Vehicle Diesel Engines

ASME/IEEE 2007 Joint Rail Conference and Internal Combustion Engine Division Spring Technical Conference ◽

10.1115/jrc/ice2007-40018 ◽

2007 ◽

Cited By ~ 3

Author(s):

Zhaowen Wang ◽

Ronghua Huang ◽

Xiaobei Cheng ◽

Yiwei Huang ◽

Jie Shen ◽

...

Keyword(s):

Diesel Engine ◽

Numerical Simulations ◽

Cylinder Head ◽

Thermal Load ◽

Flow Distribution ◽

Maximum Temperature ◽

Heavy Duty ◽

Water Jacket ◽

Thermal Cracks ◽

Heavy Duty Vehicle

The paper has explored the solutions to the thermal overload in the cylinder head of a heavy-duty vehicle 6-cylinder diesel engine and the thermal cracks in the valve-bridge of the engine. The experiments include measuring the temperature of the cylinder head bottom and testing the flow distribution of coolant through the upper nozzles of cylinder head bottom. The follow-up analysis was conducted on the causes of the excessive thermal load of the cylinder head bottom, the thermal cracks in the valve-bridge region, and the rationality of the structure of the water jacket for the cylinder head. The mechanism of the water jacket of cylinder head was further inquired. Then 3-D CFD numerical simulation of water jacket in the sixth cylinder, which is in the worst cooling condition, is performed. To enhance the flow form in water jacket and lower the cost of enhancement, we proposed 4 schemes of water jacket and conducted the numerical simulations to these schemes. It was identified that all these schemes have efficiently improved the flow field in water jacket. In the typical proposed scheme 1 in which 6 nozzles of all the 10 upper nozzles were blocked, the coolant flow rate on the bottom of the water jacket and in the cylinder head valve-bridge region increased by about 68.73%. The measuring results of the cylinder head bottom temperature show that the maximum temperature in the valve-bridge region of cylinder head is reduced by 9.2 °C and the temperature gradient reduction is 19.55 percent, suggesting that the thermal load and thermal stress of the studied diesel engine cylinder head has been significantly lowered.

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Analysis of the engine test cycles from China VI heavy duty vehicle standard and China automotive test cycle

E3S Web of Conferences ◽

10.1051/e3sconf/202126801020 ◽

2021 ◽

Vol 268 ◽

pp. 01020

Author(s):

Xiaowei Wang ◽

Chuanqi Wang ◽

Tao Gao ◽

Tengteng Li ◽

Hailiang Lao

Keyword(s):

Regression Analysis ◽

Diesel Engine ◽

Vehicle Emission ◽

Engine Test ◽

Heavy Duty ◽

Test Cycle ◽

Emission Standard ◽

Exhaust Temperature ◽

Heavy Duty Vehicle ◽

Low Load

This paper studied the engine test cycles including world harmonized steady cycle (WHSC), world harmonized transient cycle (WHTC) , china heavy-duty steady cycle (CHSC) and china heavy-duty transient cycle (CHTC) based on a diesel engine which meet the China VI heavy duty vehicle emission standard. The results show that regression analysis of speed, torque and power all meet the requirements of the China VI heavy duty vehicle standard. For this engine, NOx, PM and THC pollutants under CHSC are 134.5%, 29.6% and 94.4% higher than those under WHSC, respectively. PN emissions of CHSC is 65.6% lower than that of WHSC. NOx, PM and PN pollutants under CHTC are 62.9%, 96.4% and 64.3% higher than those under WHTC, respectively. The exhaust temperature of the first 350 seconds at CHTC is lower, which poses a greater challenge to the conversion efficiency of the after-treatment system at low speed and low load.

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The torsional vibration simulation of the diesel engine crankshaft system based on multi-body dynamic model

Proceedings of the Institution of Mechanical Engineers Part K Journal of Multi-body Dynamics ◽

10.1177/14644193211020247 ◽

2021 ◽

pp. 146441932110202

Author(s):

Mengsheng Wang ◽

Nengqi Xiao ◽

Minghui Fan

Keyword(s):

Diesel Engine ◽

Torsional Vibration ◽

Silicone Oil ◽

Engineering Application ◽

Simulation Software ◽

Dynamics Simulation ◽

Three Dimensional Model ◽

Body Dynamics ◽

Multi Body ◽

Engine Crankshaft

In order to analyze the torsional vibration of the crankshaft system, a three-dimensional model of the crankshaft system is established, consisted of the piston, connected rod, crank shaft, flywheel and silicone oil damper. Use by multi-body dynamics simulation software ADAMS, created the multi-body dynamics model of the multiple degrees of freedom consisting of rigid hybrid engine system, to do the torsional vibration response simulation, analysis of the torsional vibration on the crankshaft. Through the torsional vibration test of the diesel engine crankshaft system, the accuracy of the simulation calculation results have been verified. This simulation result has higher accuracy, and this calculation method has certain engineering application value.

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