车用LNG供给系统排压气体收集利用装置

基于安全性考虑,车用LNG供给系统设有超压气体泄压装置,在使用过程中一旦超压,泄压装置即工作排气。一般情况下,超压气体直排至大气,若天然气聚集浓度较高易带来安全隐患,同时造成燃料浪费,影响车辆使用经济性。车用LNG供给系统排压气体收集利用装置能够自动收集储液罐排出的超压气体,并提供给发动机使用,这样不但可以改善天然气高浓度造成的安全隐患,还能够提高燃气利用率及经济性,带来更大经济效益。     

汽车制动储液罐最低容积设计

简要分析影响制动储液罐最低容积的因素,并结合实例给出一储液罐最低容积的计算过程。     

宝马新3系车行驶中车内右前方有异响

<正>故障现象一辆宝马新3系车(F30/F35)车,在行驶过程中车内右前方偶尔会发出"嗒嗒"声,经过连续不平的路面时,异常产生的频率较高。故障诊断起初笔者依次拆下了右前车门门板、手套箱及右前A柱饰板(包括右前脚部侧饰板),并调整了发动机室盖铰链固定螺栓,但异响仍然存在,后来通过不断路试终于发现异响是由洗涤器储液罐上部固定卡槽在其安装支架内移动产生的。故障排除首先拆下洗涤器储液罐,用清洁剂清除其上部固定卡槽上的     

东风EQ2050系列“猛士”车制动系常见故障分析

制动灯报警当制动储液罐液面过低时有报警灯指示。报警灯亮起，首先检查踏板状况和储液罐液面高度．再检查液压管路是否泄漏。     

2020年一汽奥迪A3新技术剖析(三)

(七)SCR系统(选择性催化净化还原系统)1.结构如果车上配备有多联杆式后悬挂的话,SCR储液罐的加注量是12L。如果车上配备有扭转梁式悬挂的话,SCR储液罐的加注量是13L。这个SCR储存罐由一个模压罐和一个总成(该总成内包含有供液泵、质量传感器、加热器、过滤器和温度传感器)构成。在注液管颈上装有一个售后服务用的通气装置。这个供液总成在售后服务中是可以单独更换的。     

全断面竖井掘进机上排渣关键技术研究与试验

为解决竖井掘进机施工过程中竖向排干渣的难题，提出全断面竖井掘进机上排渣技术。首先，介绍上排渣系统的技术原理和排渣能力；然后，针对岩渣粒径控制技术、刮板输送机刮渣技术、刮渣盲区清渣技术、斗式提升机转渣技术进行研究；最后，进行不同推力和转速等多种工况下的掘进试验。结果表明： 上排渣技术可行，岩渣粒径可控，排渣系统运转正常。全断面竖井掘进机上排渣技术，为竖井掘进机机械化连续排渣提供了一种可行可靠的方法，有利于促进竖井掘进施工技术的进步。     

钻孔灌注桩施工中循环液循环问题的分析

1 概况 随着我国经济的迅速发展,钻孔灌注桩在基础工程中的应用越来越广泛。早期许多施工单位普遍采用正循环钻机进行钻孔灌注桩的钻孔,施工中均不同程度发现排渣效果差及钻孔进度缓慢的情况。2 钻孔中循环液循环问题的分析 钻孔灌注桩基础的施工采用正循环钻机进行钻孔施工,另配备1.5t以上冲锤使其配合嵌岩的施     

轿车故障排除两例

案例1：一辆奥迪A6轿车在市区行驶时,冷却液温度报警灯亮,冷却液从储液罐上盖中溢出,同时电子冷却风扇停转。     

警惕剩磁引起空调压缩机工作异常

近日有2辆客车的空调陆续出现制冷效果变差的故障.空调安装在使用不到2年的客车上,配装的是型号为MD8-e的日立电装空调,空调系统属于车顶组装型式.其主要部件安装在车顶上,包括冷凝风机、储液罐、膨胀阀、蒸发器、蒸发风机等均安装在车顶,平时保养也较到位.这种空调制冷效果为什么会变差呢? 该日立电装空调的制冷循环如图1所示,其特点是有2个独立的制冷循环系统.在空调压缩机运转时排出高温高压气体制冷剂,经管道流入冷凝器,在冷凝器内热量被风机带走后,气态制冷剂冷凝为液态制冷剂流入储液罐,流经泄压阀进入过冷器,再通过干燥器流入膨胀阀,进入蒸发器中被逐步蒸发成气态.制冷剂完全气化变成低温低压的气态后,会吸收空气的热量,再回到压缩机而形成制冷循环,并使蒸发器周围空气变冷,被鼓风机吹出达到制冷的目的.     

东风EQ2050型猛士汽车的正确保养

<正>冷却系的保养冷却液的检查与添加。冷却液不足时,仪表板上冷却液液面报警灯点亮,提示需要添加发动机冷却液。其方法和注意事项是:①观察膨胀水箱储液罐液     

单向阀在沼气吸渣车抽排管路系统中的运用

随着真空泵在吸污车、吸粪车等环卫专用车辆上的广泛运用,其润滑、密封所用的机械油的散失成为一个无法回避的问题。通过介绍分析、改进经过,提出了一个解决此问题的有效办法。     

某车型高原试验熄火验证

汽车在行驶过程中熄火会突然失去动力及造成转向和制动性能下降,危害严重.针对某车型在地区适应性试验过程中发生多次熄火的现象,进行油泵熄火验证试验,测得熄火时油轨压力瞬间下降,找出熄火原因为油泵抗气阻能力差.采取燃油泵储油桶引射口增加隔板,增大油泵底座外轨排气孔和进油口尺寸等方法,可有效提高油泵的抗气阻能力.该方案通过了道路测试的验证,为如何设计油泵来抵抗油箱气阻提供了一些依据.     

汽车发动机机油泵壳体加工工艺优化

以TU5JP4汽车发动机机油泵为研究对象，其主要使用在神龙汽车有限公司系列乘用车发动机中。在该款机油泵加工制造过程中，壳体是其主要加工部件，所占生产时间最长，是影响机油泵的整体生产效率的主要要素。对现有机油泵壳体加工工序做了分析并进行了时间测量，每件产品加工时间为597s；采用更改刀具和工艺参数以及更改毛坯设计的方法改进后，每件产品加工时间缩短为463s，该改进为有类似结构的机油泵壳体加工提供了参考。     

一种无有害气体排放的新型吸粪车

目前使用的真空吸粪车作业产生大量臭气,且除臭装置效果不佳,严重污染环境空气。通过研究,提出了在抽吸罐中加入隔膜,隔离抽入罐体内的粪液与排出罐体外的空气之间的接触,从而达到减少臭气及致病细菌排放的新型真空吸粪车技术方案,并设计制造了一台样机。通过多项性能试验证明,该样机具有作业过程臭气零排放,同时有效容积、抽吸速度、强排效率、强排速度等各项基础性能指标均达到或优于原有吸粪车,且彻底解决了吸粪车作业时可能发生的抽冒问题。     

生物制气发动机最大扭矩转速燃烧排放分析

介绍了采用气化炉热解气化各种农林废弃的生物质,得到可燃生物制气。将柴油机改制成柴油/生物制气双燃料发动机进行试验,用生物制气作为主要燃料,由柴油引燃。测量生物制气/柴油双燃料发动机在最大扭矩转速时的气缸压力及废气排放,分析燃烧特性及对排放物生成的影响,并对比分析柴油机与双燃料发动机的差别。     

Numerical and experimental investigation of lubricating oil flow in a gerotor pump

Gerotor pumps are widely used in the automotive industry for engine oil lubrication, due to their high volumetric efficiency and smooth pumping action. In many cases, the lubricating oil from the sump is mixed with contaminants, such as dust and tiny solid particles, or becomes thickened, due to aging. These problems will lead to critical situations, such as increased noise, enhanced wear and erosion, and poor lubrication of the engine. These critical situations were studied by conducting a detailed CFD integrated investigation on a gerotor pump’s performance at different operating conditions in three phases, and the results are presented in this paper. In first phase, a CFD model of a gerotor pump was developed with a dynamic mesh for the rotary movement of both the inner and outer rotors. The effects on pump flow rate of important parameters, such as rotor speed, fluid viscosity and number of ports, were simulated using non-contaminated oil at room temperature and an elevated temperature of 140oC. The relationship between flow rate and pressure at different rotor speeds was predicted and validated with test data for further parametric study. The pressure ripples at different time steps were measured at different angular positions of the rotors to examine the model accuracy. It was found that the flow rate increased and pressure pulsation, as well as flow recirculation, was reduced when ports were added to the cover plate. A suction pipe with a strainer was added for the second phase to capture the undesired changes in flow behavior, such as cavitation, which is caused by negative suction at the inlet region of pump. A suitable size for the inlet suction pipe for this pump was chosen after performing tests to characterize the flow behavior with single and double ports. Next, the relationship between pressure drop and strainer porosity was determined using different porosity values for the strainers. In the final phase, oil with different concentrations of solids was simulated to measure the effect of solid particles on flow rates and pressure losses. It was observed that the intensity of the recirculation was reduced at the suction end at the higher concentration of 0.04%, due to particle inertial effects. It was also found that particle size distribution affected the overall efficiency and pressure head of the pump.     

Lubrication characteristics of spiral groove liquid seals for use in the carrier of a vane-type external LPG fuel pump

We analyzed the lubrication characteristics of a design-selected spiral groove liquid seal for the critical component, the carrier, of a rotary vane-type fuel pump developed for external installation on fuel tanks for liquid phase LPG (liquefied petroleum gas) injection (LPLi) vehicles, with the aim of fundamentally improving lubrication performance and so protecting the carrier from early frictional wear damage at its suction face. The main reason for selecting a spiral groove pattern was because the viscosity of liquid LPG is very low, comparable to that of air, and current commercial dry gas seals adopting spiral grooves have been successfully employed in completely noncontacting applications. Utilizing the Galerkin finite element lubrication analysis method, a detailed lubrication characteristic analysis of the seal was performed, and lubrication performance optimization was performed by systematic parameter analyses of the design variables. Compared to the initial reference design, the final optimized spiral groove seal design had a groove depth increased by 66.7% and an equilibrium seal clearance increased by 65.3%. Our model also predicted that under a condition of equilibrium between the closing force of the pumping pressure and the seal opening force, the optimally designed carrier spiral groove liquid seal was capable of maintaining a stable lubricating film with sufficient axial stiffness and thereby demonstrated successful noncontact operation; in addition, leakage through the seal was minimal.     

一种新型绿化喷洒车液位计的应用

设计了一种新型绿化喷洒车液位计,具有高、低位智能声光报警功能,在液体加注过程中能够避免罐体满溢,在车辆进行绿化喷洒作业过程中能够避免因液泵空转造成的液泵损坏。     

提高面向中东市场乘用车的空调降温性能

某款乘用车出口中东市场,出现空调停止工作及空调降温性能不能满足当地高温环境要求的问题。经过分析并对发动机水泵、散热器、冷却风扇进行了改进,改进后的样件装车测试,空调工作不再出现停机现象,空调降温性能达到了中东地区高温环境的要求,此款乘用车可以顺利出口到中东市场。     

捷达轿车以液化石油气为燃料的研究

利用国产液化石油气装置，对捷达轿车的燃料供给系统进行了改造，使之既能燃用汽车又能燃用液化石油气。论述了所采用的液化石油气装置的组成，并对其主要部件的结构、工作原理等进行了介绍。对该车进行了调试、试验、并与燃用汽油时的排放情况进行了对比分析。