Heat dissipation characteristic in the intake grille and radiator of a fuel cell vehicle

ABSTRACT

In this study, a three-dimension (3D) computational model was proposed to investigate the flow and heat transfer characteristics of the intake grilles of two different fuel cell vehicles. The models of the intake grilles were constructed according to the actual sizes of two vehicles, namely, Roewe 950 and Toyota Mirai, considering the heat dissipation unit to simplify the heat transfer model of the vehicle. The results showed that relative to Roewe 950, Mirai intake air flow rate was approximately 10% higher, the heat transfer capacity was approximately 7% higher, and the intake grille area was larger. The coolant outlet temperature of Mirai was lower than that of Roewe 950, which was beneficial for the long term and stable operation of a fuel cell. This comparative study provided guidance for the intake grille and radiator design of fuel cell vehicles. The only difference between fuel cell vehicles on the market and conventional vehicles was that in the former, the internal combustion engine was replaced with a fuel cell stack, which had insufficient heat transfer capacity because of the reducing temperature difference. Increasing the intake grille area and the heat exchange capacity of the radiator were the key issues for the development of fuel cell vehicles. In this study, an optimal window opening angle of the radiator fin of 23° provided a maximal heat transfer coefficient.     

河口切变锋引起的滩槽泥沙交换效应

切变锋是河口湾锋系中最为常见和最易观察到的锋面类型。本文对长江口的切变锋进行现场观察和滩，槽同步水文资料分析，简述了长江口切变锋发生的部分和基本特性，提出了切变锋引起的滩，槽泥沙呈现螺旋形交换形式等论点。     

三峡库区水土流失特点及其环境危害防治措施探讨

水土流失是三峡库区主要环境问题之一,也是库区产生大量泥沙的根本因素,更是造成库区人民生活贫困的根源。本文就三峡库区水土流失的特点及其环境危害作了分析,提出了相应的防治措施,为水土流失防治工程提供科学依据。     

关于长江产业带建设总体布局的初步思考

重点开发长江是90年代中国经济重大战略布署。将长江产业带建设成具有强大经济实力的国家一级经济轴线,宜采用分层次推进与中心辐射相结合的发展战略,以浦东开发和三峡建设为契机,加强基础产业,发展新兴产业和第三产业,优化产业结构,以能源和交通建设先行,改善基础设施。同时,要协调产业带建设与浦东开发、三峡工程建设的关系。     

长江三峡柑桔的冻害和热害（二）

本文从柑桔冻害和热害的危害因子和指标等级划分的研究和选取入手,着重探讨了长江三峡地区(湖北境内)两害显著的时空变化特征、差异与关联性及对柑桔生产的影响;揭示了80年代以来冬暖春热的重大气候变化是使两害向“两极分化”的根本原因;讨论了三峡水利工程对两害时空格局的可能调整及减灾原理;最后提出了可能的对策。     

Prenatal ultrasound diagnosis of Toriello–Carey syndrome

Toriello–Carey syndrome is a rare malformative complex, described for the first time in 1988, characterized by agenesis of the corpus callosum, facial anomalies, cardiac defects and hypotonia. Relatively few neonatal cases have been reported. We describe here the first prenatal ultrasound diagnosis of the syndrome based on the detection of agenesis of the corpus callosum and spongious cardiomyopathy in a 22-week-old fetus of a couple with positive family history. The first sib of the couple was diagnosed with Toriello–Carey syndrome at 1 year of age, and had, in addition to the typical facial anomalies not detectable by ultrasound, agenesis of the corpus callosum and the same heart lesion (spongious cardiomyopathy). This report demonstrates that prenatal diagnosis of Toriello–Carey syndrome is feasible in the second trimester of pregnancy. Copyright © 2002 John Wiley & Sons, Ltd.     

Prenatal diagnosis of Apert syndrome: report of two cases

Two de novo cases with Apert Syndrome detected prenatally are presented herein. In the first, fetal ultrasound findings of syndactyly of the hands, craniosynostosis and proptosis resulted in a prenatal diagnosis in the nineteenth week of gestation. This is the earliest prenatal diagnosis of this syndrome in a not-at-risk case. Following counseling, this pregnancy was terminated and subsequent pathological examination and DNA analysis confirmed the diagnosis of Apert Syndrome and coarctation of the aorta. In the second case, fetal ultrasound at 21 weeks' gestation revealed a hypoplastic left heart and clover-leaf skull. Following counseling, this pregnancy was also terminated. Further examination of the fetus and DNA analysis led to a diagnosis of Apert Syndrome. These cases emphasize the need to complete a thorough fetal ultrasound in cases with potentially lethal cardiac abnormality and the importance of incorporating a fetal pathologist, as well as a medical geneticist, in the investigations performed after delivery or pregnancy termination when a fetal abnormality is detected on ultrasound. Copyright © 2003 John Wiley & Sons, Ltd.     

Prenatal diagnosis of congenital cystic adenomatoid malformation of the lung by fetal lung biopsy

A case of type III congenital cystic adenomatoid malformation of the lung was successfully diagnosed prenatally by fetal lung biopsy. We performed this procedure at 22 weeks of gestation, using a biopsy gun system under ultrasound guidance. The pregnancy was undisturbed by the procedure but as the condition was incompatible with life, an abortion was performed. The diagnosis was confirmed at post-mortem examination. Fetal lung biopsy appears to be a useful method for prenatal diagnosis of fetal lung disorders.     

三峡工程与长江中游沿江产业带建设

讨论了长江中游沿江产业带发展条件、限制因素和未来发展，指出三峡工程的建设将对长江中游产业的布局和经济发展带来深刻的变化；防洪作用促进中游两岸大型工业项目的兴建，调整现有沿江城镇的布局，使之结构趋于合理化；电力供应经解能源的紧张状态，改善航运条件，发挥长江黄金水道的综合效益。当然，由于坝下河道冲刷，对现有的码头带来一定的影响，由于冬季水位抬升引起两岸低湖田地下水位上升，加剧两岸土壤潜育化和沼泽化。     

2002年3-6月国内安全事故数据

统计了2002年3-6月国内发生的各种安全事故871起,包括矿业事故、交通事故、爆炸事故、火灾、毒物泄露和中毒及其他事故.统计表明,在这些事故中,矿业事故最多,占61. 8%,平均每天4.5起事故,其次是交通事故(16.3%)、爆炸事故(6.7%)、火灾(6.0%)、其他事故(5.6%)、毒物泄露和中毒(3.7%).871起事故共死亡2 197人,伤3 321人,死亡人数的百分比分别为矿业事故53.7%、交通事故28.0%、火灾6.1%、爆炸事故5.9%、其他事故5.1%、泄露中毒1.2%;受伤人数的百分比分别为泄露中毒37.4%、交通事故26.9%、爆炸事故14.2%、矿业事故11.8%、其他事故5.3%、火灾4.4%.