汽车空调风道的优化设计

汽车空调风道送风性能的好坏直接影响乘坐舒适性,因此为了提高风道送风性能,文章从影响风道系统的设计因素和风道中压力损失两方面分析空调风道设计的具体要求和方法,并基于某空调出风口风道结构优化前后的流场特性进行CFD仿真分析对比,结果表明应尽量减少风道中的压力损失以及风道转弯,降低空调风道空气阻力,提高风道送风性能,该方法对今后汽车空调风道系统设计具有参考价值。     

自动空调

随着汽车电子化程度的提高,汽车空调的操纵控制系统也不断向自动微调智能化方向发展。汽车空调的制冷系统本身的制冷循环工作都是自动进行的,有一套自动保护措施和冷量自动调节措施(防止蒸发器表面结霜),但空调系统的送风性能控制有手动、半自动和全自动三种。送风性能是指送风温度与湿度、送风速度、送风方向、空气清新度和洁净度等。     

某VAN客车空调各出风口出风量分析及优化

以某VAN客车顶置空调风道实体模型为分析对象,模拟了空调风道内部气流分布,分析了空调风道各出风口的风量分配。通过对客调出风口结构的优化,使空调风道各出风口的体积流量趋于均匀,各出风口体积流量标准差、空调风道压力损失有所降低,各项指标得到明显改善,优化效果显著。     

城市客车空调系统送风风道应用浅谈

主要介绍了城市客车空调系统送风风道的作用、材质及优缺点,并提出未来城市客车空调系统送风风道的发展方向。     

城市客车内饰风道设计简述

城市客车内饰风道设计的好坏对车辆的运行性能似乎没有什么影响,往往容易被忽视。风道不仅影响到内饰的美观而且对空调客车内室的保温、减少空调系统的损失,提高运行经济性起到至关重要的作用。这里对城市客车风道的结构设计、材料应用及其隔热措施保温提出了自己的见解,并着重叙述了风道的保温。     

大客车空调的选型与风道的匹配设计

本文分析了传统大客车空调选型和风道设计的缺陷，提出了车厢内部热负荷的分布情况确定空调机组的参数、设计空调风道及出风口的数量，根据空调风机的性能曲线及风道阻力匹配的原则高速风道截面尺寸。     

汽车空调送风口的空气流动规律浅析

为改善汽车空调气流质量，以送冷风为例浅析了汽车车厢内空调气流组织中送风口空气流动的等温自由射流和非等温自由射流规律，分析了送风口的形状及位置，送风射流参数、车厢内几何形状及热源等因素对车厢内气流组织的影响，提供了送风气流计算方法和计算公式，为设计空调室和调整车厢气流组织提供了依据。     

轻型卡车除霜系统优化分析

汽车空调除霜性能对汽车驾驶和交通安全非常重要,文章利用CFD方法对某型卡车的除霜性能进行了分析,并对除霜风道进行改进,最终得到了满足设计要求的除霜系统。     

汽车空调风道流场分析与结构改进

针对某汽车车内热-流场分布不合理而影响乘员热舒适性的问题,通过激光扫描和逆向工程建立原空调风道的几何模型,在建立合理的流体力学网格模型的基础上,采用Realizable k-ε两方程湍流模型和"壁面函数法"对风道内的流动进行流体力学稳态仿真计算,分析了原风道各出风口流量分配不合理的原因,并对原结构进行了优化设计和改进,使各出风口的流量满足设计要求,从而保障乘员的热舒适性,为汽车空调风道设计和优化改进提供依据。     

汽车空调吹脚风道结构改进及对驾驶员舒适度影响分析

文章利用CFD软件和假人模型,对驾驶员脚部感知的风速压力和气流流线分布进行分析,指出原设计的不合理处,并对其结构设计提出改进。通过结果对比,改进后驾驶员左右脚部风速明显提高,气流走向更合理,提高了驾驶舒适度,为汽车空调吹脚风道的结构设计提供参考。     

电动汽车 CO2热泵空调制热性能分析

为提升电动汽车CO2热泵空调的系统性能及扩宽热泵空调的使用温区，构建了回热器+补气增焓的跨临界CO2系统，通过建立数值模型对该系统的制热性能进行了仿真分析。研究结果表明，气体冷却器压力对制冷系数 （Coefficient of Performance，COP） 影响较大，且存在最优气体冷却器压力和中间补气压力使COP达到最大值；中间补气过程能有效提升COP和制热量，且能有效降低压缩机排气温度；回热器过热度对COP和制热量影响较小，但会导致压缩机排气温度上升。     

汽车空调风道系统CFD研究与优化

基于对某种风道的CFD分析。对后风道和中心导风管进行了优化设计，改善了风量分配同时增加了总风量。分析结果显示改进能够满足要求。     

某乘用车空调系统配气比及气动噪声分析优化

空调系统设计与布置合理与否直接影响乘员舱内舒适性。空调系统设计要求配气比必须满足标准要求,而且风道的气动噪声必须控制在合理的范围内。本文通过对某乘用车空调系统原方案进行配气比及气动噪声分析,对空调系统风管内流场分布以及气动噪声源产生与传播进行了详细分析,从而提出两种优化方案。通过配气比及噪声试验,3#优化方案满足配气比标准要求,并且驾驶员右耳处噪声较原方案降低3.7dB,效果显著。     

Tracked Air Cushion Vehicle Suspension Models: Analysis and Comparison

In this paper several dynamical models of fluid suspensions for tracked air cushion vehicles are analyzed and compared. Specifically, the models considered conform to: a fifth-order linear suspension, a nonlinear configuration with a constant supply pressure, a nonlinear model with compressor characteristics, and a sixth-order nonlinear model with a supply duct connecting the compressor to the cushion chamber. Nonlinearities included in the analysis are the flexible-skirted cushion capacitance, cushion entrance and exit orifice restrictions, feeding system duct fluid capacitance, and compressor pressure-flow characteristics. Temporal responses are obtained for guideway and external force inputs. Back flow conditions under which the supply compressor can stall are examined. It is shown that the general behavior resulting from linear analysis is in many respects similar to that obtained from the nonlinear analysis. Thus, a linear model could provide a good initial basis for a preliminary design and performance specifications.     

Tracked Air Cushion Vehicle Suspension Models: Analysis and Comparison

ABSTRACT

In this paper several dynamical models of fluid suspensions for tracked air cushion vehicles are analyzed and compared. Specifically, the models considered conform to: a fifth-order linear suspension, a nonlinear configuration with a constant supply pressure, a nonlinear model with compressor characteristics, and a sixth-order nonlinear model with a supply duct connecting the compressor to the cushion chamber. Nonlinearities included in the analysis are the flexible-skirted cushion capacitance, cushion entrance and exit orifice restrictions, feeding system duct fluid capacitance, and compressor pressure-flow characteristics. Temporal responses are obtained for guideway and external force inputs. Back flow conditions under which the supply compressor can stall are examined. It is shown that the general behavior resulting from linear analysis is in many respects similar to that obtained from the nonlinear analysis. Thus, a linear model could provide a good initial basis for a preliminary design and performance specifications.     

Performance of air conditioners with a gas-liquid separation condenser and one-tank laminated evaporator

In this study, a parallel flow condenser and laminated evaporator for an automotive air-conditioning system were modified to improve performance. Gas-liquid separation type condensers, in which the condenser and receiver drier are integrated, and one-tank laminated type evaporators were developed, and their performances were investigated experimentally using HFC-134a. Heat transfer characteristics in the condenser are examined by means of air temperature, air velocity entering the condenser and inlet pressure of the refrigerant; heat transfer characteristics in the evaporator are examined by means of air temperature, relative humidity, flow rate of air, outlet pressure of refrigerant and superheat. Pressure drops for both evaporator and condenser are also measured, and correlations for pressure drop are derived for the condenser and evaporator, respectively. Air velocity and mass flow rate of the refrigerant have a significant effect on the overall heat transfer coefficient, and flow pass is not significantly influenced by the cooling capacity of the condenser. The overall heat transfer coefficient of the evaporator increases as air flow rate, air temperature and relative humidity increases.     

高海拔特长隧道低压低氧环境施工控制技术研究——供氧技术标准、关键通风技术、施工人员组织、施工装备效率

为解决高海拔地区低压和低氧环境带来的隧道施工供氧、通风等技术难题,采用现场试验及测试的方法,对高海拔隧道施工人员缺氧状况、供氧效果、机械排污量等进行研究,结合理论推导及数值计算,得到如下结果:人体的缺氧危险等级分为严重缺氧(Ⅰ)、缺氧(Ⅱ)、存在缺氧危险(Ⅲ)和不缺氧(Ⅳ)4级;基于肺泡氧分压与氧气体积分数关系的不同缺氧等级下的氧气体积分数控制标准;不同海拔CO体积分数控制标准模型;基于风管开口处流量理论的风管漏风率海拔修正系数计算公式;风机风压、功率的海拔修正系数公式;考虑人体劳动的平均能量代谢率海拔修正系数的不同海拔下施工人员劳动强度指数及强度等级。     

某轻型客车采暖的理论分析与试验

为适应客户不断提高的乘坐舒适性,汽车空调设计开发也在不断提高自身水平,以满足市场需要。原有的空调设计、试验、整改、再验证的手段已经逐渐不能适应产品开发周期。空调的设计开发需要依靠一定的理论计算,为系统匹配、及整改方案提供理论依据。本文通过使用建立的理论分析模型,定性的、定量的对某轻型客车采暖性能问题进行分析,并提出整改验证,试验证明本文的理论分析模型方向是正确的。     

双蒸发器汽车空调系统的改进

分析了传统的双蒸发器设计存在的出风口温差大、油循环率低等问题，对其汽车空调系统进行了改进，即采取了在顶置蒸发器处分液并在吸气管道上增加一个压力平衡装置的设计。通过环境模拟试验和油循环率试验对改进设计进行了验证。试验结果表明，蒸发器出风口温差明显减小，油循环率明显提高。