【作者】 朱伏龙；

【导师】 陈杰；

【作者基本信息】 上海交通大学 ， 车辆工程， 2008， 硕士

【摘要】 真空吸尘车是一种利用负压工作的新型路面清扫车辆。吸尘口是其气路系统的关键部件,对吸尘效率、气路阻力、工作可靠性有决定性作用。国内扫路车主要有吸扫结合式、纯吸式、纯扫式三种,吸扫结合式占主导地位,但纯吸式在特定场合有很大优势,逐渐成为扫路车的一个重要的发展方向。文章首先分析了真空吸尘车的工作物质即空气和固体尘粒的物理性质,阐述了空气的流动规律及其二者之间的力学作用,从流体力学角度概括了尘粒起动的原理:在气流作用下尘粒之间发生碰撞,碰撞所产生的冲击力引起尘粒的起跳。计算了砂石、煤粉、水泥、铁粉、铁片及铁矿石等尘粒的起动速度,为吸尘口设计提供了理论依据。其次,分析了吸尘口的结构参数:排气口面积S、吸尘口长L、宽度B、收缩角α、倾斜角β。S决定了在一定流量的条件下排气管的气流速度,该速度决定了吸尘口输送尘粒进入集尘箱的能力。L关系到吸尘车的单次作业宽度,L越大单次作业宽度越大,但同时会降低吸尘口边角的吸尘效果。B关系到侧面进气的流量值和尘粒是否有足够的起动时间。收缩角α越大,吸尘口内的速度分布越不均匀,压力损失越大,一般不应超过150°。适当增加倾斜角β有助于降低气流带走尘粒的难度。再次,进行了吸尘口结构创新,建立了吸尘口参数化实体模型,该模型能实现所有参数可调,有效缩短设计周期。通过计算流体力学分析了所选设计方案的流场分布,流场分布表明设计方案存在一定的合理性。为检验吸尘口设计方案的可行性,设计制造了用于吸尘口实验的实验台,该实验台运用变频调速原理实现风机转速连续可调。通过实验对设计方案进行了实验分析和论证,吸尘口的各项指标满足了设计要求。大量的现场试验验证了吸尘口能够有效吸清多种尘粒与粉尘,满足了实际使用的要求。更多还原

【Abstract】 Vacuum sweeper vehicle is a kind of new road sweeping vehicle which applies minus air pressure. Dust sucking mouth is one of its key parts and decides dust sucking efficiency, air resistance and work reliability.There are three types of road sweeping vehicle in domestic. They include the combination of sucking and sweeping vehicle, only sucking vehicle and only sweeping vehicle. At present ,the first kind dominates the domestic market, but the vacuum sweeping vehicle is becoming popular because of its good performance in some special working condition. So the vacuum sweeping vehicle is an important development direction. This paper analyzed physical character of working material as air and dust particles, the principle of air flowing and the force interaction between air and dust particles. It explained the particle pick-up principle from the angle of hydrodynamics. The principle is that solid particles collide with each other under the effect of air flow and the wallop caused the pick-up of dust particles. It computerized the pick-up speed of rock, coal powder, cement, iron powder, iron piece, iron mineral, which supplies academic basis for dust sucking mouth designing. It analyzed the structure parameters of dust sucking mouth: vent face area S, its length L, width B, shrinking angleα, tilting angleβ, and pointed out their influence on the sucking efficiency. S is related to air flow speed in the vent tube under a certain flux and this speed decides the ability of dust sucking mouth to send the particles to the collecting box. L is associated with the single working width. The single working width increases with the increase of L. But too long L will decrease the side sucking ability. B is related to the flux of the side entrance and whether there is enough time for the particle’s pick-up. The increase of shrink angle will decrease the equity of air speed distribution in dust sucking mouth, increase pressure loss and generally it must be less than 150°.A smaller titling angleβwill reduce the degree of difficulty in taking away the particles by air flow. Then it designed innovative structure of dust sucking mouth and it built the parameterized solid model and all parameters of this model are adjustable, which shortens the designing period. It simulated the flow field distribution by CFD which verifying the rationality of the design. In order to test the sucking mouth, it also designed the experiment equipment and manufactured it. This experiment equipment applied frequency conversion to change the fan speed continuously. The experiments on the experiment equipment indicated the designed dust sucking mouth had met the designing index. Lots of experiment on the spot verified that this design of the sucking mouth was successful in sucking kinds of dust particles and meeting the practical needs.更多还原