电控发动机冷却液的使用误区及避免

对于传统发动机而言,能够保证发动机正常工作的冷却液温度值为80℃～90℃左右,而对于目前常用的电控式发动机,由于其普遍采用强制循环式水冷却系统,利用水泵强制冷却液不断的循环流动,对发动机进行冷却,从而具有高转速、高压缩比和高功率的工作特点,导致机械负荷及热负荷较大,摩擦热较高,因而发动机工作时的正常水温的要求已提高到95℃～105℃.用水冷却电喷发动机已经不能满足要求,因此,无论是冬天还是夏天,电喷发动机必须使用优质冷却液作为冷却介质.     

电喷发动机三种传感器的典型故障诊断与排除

文章分析电喷发动机的氧传感器、冷却液温度传感器和节气门位置传感器的故障及其原因,并简述其检测方法。     

捷达王轿车充电灯与故障警告灯同时闪亮

一辆装有电喷发动机的捷达王轿车．在行驶时发现仪表板上的充电指示灯、冷却液温度警告灯、机油压力警告灯同时闪亮报警。     

奥迪100轿车发动机过热故障的诊断

人们的传统观念认为冷却液的温度控制在80～90℃是正常的,这一观念对货车发动机现在仍然适用,但对采用电喷发动机的轿车就不适用了.     

发动机冷却液保管使用需知

车用发动机冷却液是用于水冷式发动机冷却系统的必须液体。发动机工作时温度过高．会影响发动机的使用寿命和产生爆震，因此要采取冷却液进行散热。使用最为广泛的是乙二醇型冷却液，其使用保管应注意以下几点：①冷却液应密封存放在阴凉避光处，     

电喷汽车的正确使用与维护

电喷发动机可以精确地控制进入发动机气缸内的空气 /燃油的混合比、燃烧过程及废气转换，以达到优化发动机性能，改善燃油经济性，从而更加严格地控制所排出的废气对空气的污染程度的目的。 电喷发动机的主要控制系统是控制模块 (ECM)。它通过安装在发动机、车身不同位置的传感器及工作请求开关，对发动机工作状态进行分析，然后再通过发动机及车身上的执行器，对发动机及相应的机构进行精确的控制。电喷发动机具有优良的性能，这不仅得益于其本身的设计和软件的支持，而且还来自于电喷汽车的正确使用和维护。 1电喷汽车的正确使用 a.燃…     

奥迪轿车发动机起动困难二例

一、霍尔传感器固定座损坏故障现象:一辆已行驶12万公里的奥迪100V6型电喷轿车,正常使用中发动机很难起动;有时起动后虽能正常运转,但冷却液温度偏高,温度表指针经常指向红色区域,而且发动机动力不足、加速迟缓,汽车爬坡没劲。故障检查:根据故障现象,先从冷却系查找原因:触摸散     

夏利轿车冷却系统的使用和维护

1、发动机冷却液的正确使用 夏利轿车冷却系采用了密封系统，散热器盖是密封的，并设置了一个用塑料制成的储存冷却液的膨胀水箱，在其中加注了规定量的冷却液。当发动机工作处于热状态时，冷却液膨胀，便有部分冷却液从散热器流入膨胀水箱；当发动机冷却时，真空使冷却液从膨胀水箱吸入到散热器中，冷却液不会损失，并可消除冷却系统中的所有气泡，增加冷却液的热效率。虽然膨胀水箱中的冷地液面有时升高有时降低，散热器中总是先充满冷却液。     

电喷初级讲座(连载)汽车发动机电喷系统的基本知识(十一)

第二章电喷发动机汽车的使用与维护 第一节驾驶电喷发动机汽车的注意事项 驾驶电喷式发动机汽车与化油器式发动机汽车相比,有许多不同之处,在使用中必须注意以下事项:     

丰田大霸王车爬坡困难 冷却液温度高

一辆1995年产丰田大霸王车(装备丰田2TZ-FE电喷发动机和四速电液控制自动变速器)，在行驶了28万km后，在平路上行驶和高速公路上行驶时发动机冷却液温度都正常，但它一爬坡，散热器就“开锅”。该车发动机运转无力，只能在把变速杆置于Ⅱ位条件下(简称挂Ⅱ位，其余类推)行驶，若     

Active coolant control strategies in automotive engines

The coolant flow rate in conventional cooling systems in automotive engines is subject to the mechanical water pump speed, and high efficiency in terms of fuel economy and exhaust emission is not possible given this limitation. A new technology must be developed for engine cooling systems. The electronic water pump is used as a substitute for the mechanical water pump in new engine cooling systems. The new cooling system provides more flexible control of the coolant flow rate and engine temperature, which previously relied strongly on engine driving conditions such as load and speed. In this study, the feasibility of two new cooling strategies was investigated using a simulation model that was validated with temperatures measured in a diesel engine. Results revealed that active coolant control using an electronic water pump and valves substantially contributed to a reduction of coolant warm-up time during cold engine starts. Harmful emissions and fuel consumption are expected to decrease as a result of a reduction in warm-up time.     

基于冷却液温度的内燃机能量流试验研究

内燃机能量流试验是评估不同控制策略下内燃机能耗和指明其改善方向的重要方法。通过试验对1台涡轮增压缸内直喷汽油机进行了基于冷却液温度的能量平衡分析,基于热力学定律,将能量平衡项分为有效功、冷却液损失、排气损失和通过辐射传热产生的未计入热损失。结果表明:小负荷时,随着冷却液温度的升高,燃油消耗率略有下降,NO_x排放量增加;全工况下,HC排放量随着冷却液温度的升高而减少,CO和CO_2排放量变化不大;有效功占比和排气损失占比随负荷的增大而增大,几乎不受冷却液温度的影响;冷却液损失占比随冷却液温度的升高而减小。     

Effects of coolant channels on large-scale Polymer Electrolyte Fuel Cells (PEFCS)

Fully coupled simulations of two-phase transport in Polymer Electrolyte Fuel Cells (PEFCs) and heat transfer in coolant channels are performed in order to investigate the effects of cooling channel configuration on the distributions of temperature and water within PEFCs. When a practical coolant flow rate is applied to large-scale cells for automotive applications, a significant coolant temperature rise is expected from the coolant inlet to the outlet, particularly under high current density operations, creating a significant cell temperature gradient along the flow direction as well. Consequently, a two-phase water profile resulting from evaporation-condensation processes inside PEFCs is also strongly influenced by the cell temperature gradient from the hot coolant inlet toward the cold coolant outlet regions, demonstrating that both temperature and liquid saturation strongly depend on the thermal gradient along the coolant flow path.     

Assessment of the influence of different cooling system configurations on engine warm-up, emissions and fuel consumption

One of the major goals of engine designers is the reduction of fuel consumption and pollutant emissions while keeping or even improving engine performance. In recent years, different technical issues have been investigated and incorporated into internal combustion engines in order to fulfill these requirements. Most are related to the combustion process since it is responsible for both fuel consumption and pollutant emissions. Additionally, the most critical operating points for an engine are both the starting and the warming up periods (the time the engine takes to reach its nominal temperature, generally between 80°C and 90°C), since at these points fuel consumption and pollutant emissions are larger than at any other points. Thus, reducing the warm-up period can be crucial to fulfill new demands and regulations. This period depends strongly on the engine cooling system and the different strategies used to control and regulate coolant flow and temperature. In the present work, the influences of different engine cooling system configurations on the warm-up period of a Diesel engine are studied. The first part of the work focuses on the modeling of a baseline engine cooling system and the tests performed to adjust and validate the model. Once the model was validated, different modifications of the engine coolant system were simulated. From the modelled results, the most favourable condition was selected in order to check on the test bench the reduction achieved in engine warm-up time and to quantify the benefits obtained in terms of engine fuel consumption and pollutant emissions under the New European Driving Cycle (NEDC). The results show that one of the selected configurations reduced the warm-up period by approximately 159 s when compared with the baseline configuration. As a consequence, important reductions in fuel consumption and pollutant emissions (HC and CO) were obtained. On doctoral leave from Universidad Technológica de Pereira (Colombia)     

Reliability of Nanofluid Concentration on the Heat Transfer Augmentation in Engine Radiator

Nanofluids, the fluid suspensions of nanomaterial, became a promising fluid that is invoked when heat transfer increase is required. Using of nanofluids as a coolant in the engine radiators is a crucial topic for the thermal engines manufactrers due to the expected enhancement in the cooling process. In this study, Two nanofluids (Al₂O₃/water and CuO/water) flowing in a flat tube of radiator are investigated numerically to evaluate thermal and flow performance. The resizing process for the radiator is performed by using nanofluid instead of water flow. A significant reduction in the radiator volume is achieved due to marked improvement in the heat transfer performance while, the required pumping power after this reduction in the volume is increased over that needed for base fluid. The normalized heat transfer (heat transfer to the pumping power) is found to be a function of both Reynolds number and nanofluid concentration ratio while the ratio of the normalized heat transfer is found to be dependent only on the nanofluid concentration ratio. These dependencies are formulated as general correlations.     

非二元醇环保型发动机冷却液研究最新进展

介绍了原非二元醇型发动机冷却液和新型非二元醇型冷却液的种类,阐述了不同类型冷却液的特点,针对冷却液的毒性、冰点防护、腐蚀抑制、传热和成本等进行了分析,认为新型非二元醇型发动机冷却液在环保、防冻、防腐、传热等方面均具有良好的表现,同时兼具价格优势。讨论了非二元醇环保型发动机冷却液的应用前景和发展潜力。     

型发动机冷却水套改进及三维数值模拟分析

为了提高某V型发动机冷却性能，对该机原冷却水套模型结构分5个阶段进行了改进，包括加大左右侧排气端气缸垫通道面积，增加气缸盖和气缸体水套通道，开通气缸盖水套排气侧中间断口。利用Ricardo三维流体软件VECTIS对原水套和每阶段改进水套进行了三维数值模拟计算，并进行了比较分析。结果表明，最终改进后的水套流动性能比原水套有明显的改善。     

V型发动机冷却水套改进及三维数值模拟分析

为了提高某V型发动机冷却性能,对该机原冷却水套模型结构分5个阶段进行了改进,包括加大左右侧排气端气缸垫通道面积,增加气缸盖和气缸体水套通道,开通气缸盖水套排气侧中间断口。利用Ricardo三维流体软件VECTIS对原水套和每阶段改进水套进行了三维数值模拟计算,并进行了比较分析。结果表明,最终改进后的水套流动性能比原水套有明显的改善。     

乙二醇型汽车发动机冷却液的检测和正确使用

发动机的正常运转与发动机冷却液密不可分,本文主要探讨了乙二醇型汽车发动机冷却液的科学检测和正确使用。发动机冷却液,俗称防冻液,是发动机正常运转不可缺少的散热介质,能保持发动机在最有利的工作温度范围内运行,避免因发动机温度过高或过低带来的不良后果。根据发动机运行的情况对冷却液进行科学的检测、正确的使用和更换会直接影响发动机的使用寿命。     

长城有机型发动机冷却液试验研究

为检验有机羧酸型发动机冷却液的性能，对使用该冷却液的捷达CTX型轿车进行了8万km的道路试验。试验过程中对其理化指标、外观和气味、金属试片腐蚀情况、橡胶和树脂相容性能以及添加剂的损耗进行了测试。试验表明，全有机型冷却液中的腐蚀抑制剂在金属试片表面生成稳定的化学保护膜，可以在低pH值下为黑色金属提供足够的腐蚀抑制保护。