摘 要
全吸式干濕兩用掃路車(chē)是一種集負(fù)壓吸塵、重力沉降和垃圾運(yùn)輸為一體的環(huán)衛(wèi)裝備，廣泛應(yīng)用于干線公路、機(jī)場(chǎng)、城市住宅區(qū)和公園等的道路清掃。全吸式干濕兩用掃路車(chē)按除塵方式一般可分為濕式和干式兩種除塵方式。干式除塵方式不需要使用噴霧系統(tǒng)，不受環(huán)境溫度的限制。濕式除塵方式可有效防止微塵排向大氣，環(huán)保性能好。
全吸式干濕兩用掃路車(chē)氣路系統(tǒng)的主要工作介質(zhì)是空氣，工作對(duì)象是地面上的塵土垃圾。其工作原理為：離心式風(fēng)機(jī)在組合式吸嘴的吸塵口處產(chǎn)生負(fù)壓，同時(shí)組合式吸嘴的回吹風(fēng)腔體通過(guò)條縫狀噴口噴出封閉氣幕，在兩者的共同作用下，地面上的灰塵顆粒被吸塵口吸起，并通過(guò)排氣管道輸送到重力沉降室和旋風(fēng)分離器中進(jìn)行除塵過(guò)濾，過(guò)濾后的潔凈空氣則直接排入大氣，完成全吸式干濕兩用掃路車(chē)的主要功能。
組合式吸嘴的結(jié)構(gòu)形式?jīng)Q定了組合式吸嘴內(nèi)部的流場(chǎng)分布情況，從而對(duì)組合式吸嘴的吸塵效率產(chǎn)生影響。組合式吸嘴的設(shè)計(jì)主要涉及起塵動(dòng)力學(xué)、封閉氣幕的設(shè)計(jì)計(jì)算和空氣匯流這三方面的理論。本文以相關(guān)理論為基礎(chǔ)，結(jié)合組合式吸嘴的結(jié)構(gòu)設(shè)計(jì)原則，分析了吸塵口的面積 、組合式吸嘴的長(zhǎng)度 、組合式吸嘴的寬度 、組合式吸嘴的高度 、組合式吸嘴的收縮角 、排氣管傾斜角 這六個(gè)結(jié)構(gòu)參數(shù)對(duì)組合式吸嘴吸塵性能的影響，并以組合式吸嘴吸塵部分的局部壓力損失最小為目標(biāo)，對(duì)組合式吸嘴的相關(guān)結(jié)構(gòu)參數(shù)進(jìn)行了優(yōu)化設(shè)計(jì)。在建立組合式吸嘴和普通純吸式吸嘴物理模型的基礎(chǔ)上，利用流體仿真分析軟件Fluent對(duì)其分別進(jìn)行了數(shù)值模擬和性能分析，得出結(jié)論：具有條縫狀氣幕噴口的組合式吸嘴對(duì)地面上的灰塵顆粒有更好的吸塵效果，并且吸塵的距離更遠(yuǎn)，范圍更大。
重力沉降除塵一般被全吸式干濕兩用掃路車(chē)用作第一級(jí)除塵方式。通過(guò)對(duì)重力沉降室除塵機(jī)理的分析，得到了重力沉降室結(jié)構(gòu)設(shè)計(jì)的基本原則和性能指標(biāo)。在重力沉降室內(nèi)部的擋板，可以起到延長(zhǎng)灰塵顆粒通行路程和改變氣流流向的作用。因此，擋板形式對(duì)重力沉降室除塵效率的高低有很大的影響。為了更好地研究不同擋板形式對(duì)除塵性能的影響，本文運(yùn)用計(jì)算流體力學(xué)技術(shù)（CFD），對(duì)重力沉降室內(nèi)部?jī)煞N不同擋板形式下的流場(chǎng)進(jìn)行了仿真分析，從而得到了最佳的重力沉降室結(jié)構(gòu)設(shè)計(jì)方案。

關(guān)鍵詞 全吸式干濕兩用掃路車(chē)；組合式吸嘴；重力沉降室；CFD
Abstract
Wet and dry suction sweeper is a sanitational equipment of negative pressure vacuum, gravity sedimentational separation and garbage transport, widely used in the sweeping of trunk roads, airports, urban residential areas, parks and roads. Wet and dry suction sweeper can be divided into wet dust removal method and dry dust removal method. Dry dust removal method doesn’t need water system and regardless of the weather temperature limits. Wet dust removal method has good environmental performance and can prevent the dust into the atmosphere.
The main working medium of pneumatic system is air and work object is dust waste on the ground in wet and dry suction sweeper. The working principle is: centrifugal fan generates negative pressure in the mouth of combined nozzle, while the back chamber of combined nozzle exhausts closed air curtain through slit vents. With the joint action on the ground, the dust particles are sucked from the suction port and piped into gravity settling chamber and cyclone separators through the exhaust for dust filter. Clean air is discharged directly into the atmosphere, completing the function of wet and dry suction sweepers.
Structure of the combined nozzle determines the form of flow field inside the suction, and impacts on cleaning efficiency of the combined nozzle. The design theory of combined nozzle mainly related to dust dynamics, design calculations of closed air curtain and air convergence. On the basis of related theory and design principles of combined nozzle, the paper analyzes structural parameters of the exhaust port area S, nozzle length L, nozzle width B, nozzle height H, nozzle contraction angle α, tilt angle β of the dust tube and with the objective of local pressure loss minimization in suction of combined nozzle, optimizes the related design structural parameters of suction in combined nozzle. In the establishment of combined nozzle and ordinary pure suction nozzle, based on the use of fluid simulation software Fluent to their respective numerical simulation and performance analysis, the paper concludes that: a slit air curtain nozzle has a better effect on dust particles on the ground and also farther control range.
Gravity settling is generally used as the first stage of dust removal for wet and dry suction sweeper. With the analysis of dust remove mechanism of gravity settling chamber, the paper gets the basic principles of structural design and performance indicators. Internal baffle style in gravity settling chamber can extend the air traffic of dust particles in gravity settling chamber and change the direction. Therefore, the form of baffle has great impact on gravity settling chamber removal efficiency. Based on computational fluid dynamics CFD, the paper analyses internal flow field of gravity settling chamber under two different physical models of baffle forms to get the best gravity settling chamber design programs.

Keywords wet and dry suction sweeper；combined nozzle；gravity settling chamber；CFD

目 錄
摘 要 I
Abstract Ⅲ
第1章 緒論 1
1.1 課題研究的背景和意義 ..