Research On Working Mechanism And Parameters Optimization Of Roller For Multifunctional Snow Remover

In winter, snowfall is very common, which covers the most part of China. If thenew snowfall cannot be cleared as soon as possible in the northern region, aftercrushed by vehicles and pedestria ns repeatedly, or repeated thaw, it will become thecompacted snow with high density, high strength, and strongly bonding with the road.While in south, due to the frozen rain or sleet in winter, the road is also easy to befrozen. The road with ice is not only causing the traffic accidents, but also causing thedisruption of traffic, railwa y outa ge, and closure of the airport, which will seriouslyinfluence people's lives, industria l and agricultural production, and make a seriousloss to the nationa l economy. With the sharp development of the road and airportconstruction, the traffic government has to face a severe problem, that is, how to getrid of the compacted snow timely. As for the traditiona l ma nual deicing way, theshortcoming restra ins the effectivness, because of the time and huma n-beingconsuming, low effectiveness, sma ll removing space and potencia l unsafty factors.Due to the side-effcet of the chemica l deicing way, it is restricted in ma ny fields. Thethermal deicing method is used to ma intena nce the specia l road, with the energyconsumption feature. Fina lly, the mecha nical deicing method is suitable to ournationa l situation. It is easy to operate and the features of high effectiveness, lowpollution, which make it achieve a high development. At present, in China, thedeicing equipment ma inly includes loaders , bulldozers, graders and other engineeringmachineries. In January 2008, jet cars, tanks, armored vehicles and other equipment iseven used to help remove the freezing snow in some regions during the lowtemperaturefreezing rain and snow disaster. It shows that our country lacks thespecia lized deicing equipment. As a result, it will make a great contribution of doingresearch and designing a specia lize equipment for removing the snow and ice on theroad to ensure the safety for the vehicles , aircraft and people.Thanks to the cooperation between Jilin University and Shenyang Shanhe Machinery Factory, with their project "Study on Multifunctional Snow Remover", thethesis is based on their research and aims at the roller as the deicing equipment. Thema in content is as follow:(1) Give a introduction of the background on the topic and describe the historyof deicing technology; a summa ry of the development and future trend about thedeicing equipment production in domestic and abroad is made .(2) Analyze the physica l and mecha nical properties of the compacted ice andsnow on the road; make a summa ry of the classification and the density for thecompacted ice and snow; analyze the reason and the influential elements for thecompacted snow and ice; give a specific introduction to the intensity and correla tioncoefficients for the compacted snow.(3) Do a research on the struture and performa nce of the snow remover; Give abrief introduction to the releva nt parameters of traction engine (ZL50 loader) for thesnow remover. Make a summa ry of the requirements for kinds of performa nceparameters of the deicing devices. Based on the analysis on the host tractionparameters and de-icing performa nce parameters in the multifunctional snow remover,different kinds of de-icing device s are analyzed and make the roller as the wokingdevice for the multifunctional snow remover; make an analysis on the specificstructure and parameters for the multifunctional snow remover and the roller; make acaculation and analysis for the motion of the roller and tangentia l resista nce; on thebasis of the collaborative woking of the engine and converter, with the tractionbala nce and power bala nce of the multifunctional snow remover, the characteristics ofvehicle traction is analyzed.(4) Do a research on the working principles of the roller. Based on one tool, thede-icing process of the roller is analyzed. The process of one tool cracking thecompacted snow is divided into two stages: one is fracture crack and the other is shearcollapse crack. On the first stage, the compacted snow is experencing the elasticdeformationn, and parts of areas are forming crack and becoming compaction ofnuclear, because of the force of the tool. On the second stage, the compaction ofnuclear collaps and the crack expands, due to the further cutting of the tool. During thewhole process of fracturing, synergy exists. Lots of tools which operate collabotrallyare good at fracturing the compacted snow. On the basis of researching on the working resistance for specific tool, the working resista nce for the roller is analyzed. Establishthe breaking model for the compacted snow, after force analysis of the fracture section,apply the mohr-coulomb criterion , and get the working resista nce for specific tool.Make a Further analysis of the working resista nce for the roller.(5) Take advantage of the kinetic analysis processing, numerica l simulation ofde-icing process for the tool of the roller is made . Though eatabishing the threedimensionmodel for the tool and the compacted snow, mesh generation, making adefinition of contact and constraint,and appling load , using dynamic analysis , then theresults of numerial simulation are achieved. Make a comparative analysis for theresults, focusing on the different tool insta lla tion angles. The optimization resultindica tes that when the tool insta lla tion angle is forty degree, the stress and thedisplacement are resonable, eliminating the Stress concentration.(6) Make an experiment of the prototype, testing performa nce indicators of theprototype and verify the effectiveness of the snow remover.