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1.
介绍应用分隔扫气提高二冲程汽油机性能的试验研究,讨论分隔扫气主要参数的确定及其对发动机性能的影响,分析分隔扫气汽油机的基本特性。分隔扫气汽油机油耗率平均比原机降低14.3%.  相似文献   

2.
本文介绍丁在小型二冲程汽油机上应用分层进气和排气动力效应提高发动机性能的试验结果。最低油耗率为315g/KW·h·汽油机新鲜充量随负荷的变化趋向质调节,使汽油机在部份负荷时的性能获较大改善。发动机在中速和高速运转时,有害废气CO和HC的排放量明显减少。  相似文献   

3.
本文介绍了小型二冲程摩托车用汽油机强化时所采用的有效措施和参数的匹配。分析了压缩比、空燃比、化油器喉口及主喷阀和进排气动力效应等对发动机性能的影响。强化后使原机的升功率提高28~37%,油耗率降低10%。  相似文献   

4.
高速小型汽油机的准维燃烧模型   总被引:5,自引:1,他引:4  
建立了用于二冲程汽油机的准维湍流火焰传播模型,计算结果与试验相符合,表明准维湍流火焰传插模型对于高速二冲程汽油机具有良好的适用性。  相似文献   

5.
建立了用于二冲程汽油机的准维湍流火焰传播模型,计算结果与试验相符合,表明准维湍流火焰传播模型对于高速二冲程汽油机具有良好的适用性.  相似文献   

6.
导出了一组小型二冲程汽油机应用排气系压力脉冲效应结构的计算公式.用此公式可求得较接近实际值的结构,并给以后的试验提供了基础,可减少反复试验的工作量。付诸应用,亦能取得较好效果.  相似文献   

7.
本文介绍作者设计研制的用于汽油机的滑片式扫气泵,说明其工作原理、理论计算、设计方案、试验研究及改进措施,为设计研究汽油机增压器和二冲程汽油机扫气泵提供必要的技术资料。  相似文献   

8.
小型二冲程汽油机排气压力波的计算   总被引:1,自引:0,他引:1  
建立小型二冲程汽油机非常排气流动的数学模型,给出用特征线法解排气压力波的计算实例。在计算过程中通过迭代不断修正特征线的位置,提高了数值解的精度。计算结果与结果相当吻合。  相似文献   

9.
活塞式航空汽油机增压的模拟研究   总被引:1,自引:0,他引:1  
为了改善活塞式航空汽油机的高空性能,基于GT-Power软件,建立了活塞式航空汽油机原机和增压机模型,对活塞式航空汽油机进行了原机、一级增压及二级增压模拟研究.研究表明,涡轮增压能有效改善活塞式航空发动机高空性能,一级增压后,该活塞式航空发动机极限工作高度达到海拔7km以上;气动二级增压后,则能达到海拔8~9km,而电控二级增压后,极限工作高度将达到海拔10~11km.  相似文献   

10.
本文分析了西德Sachs Stamo 251型二冲程汽油机的结构特点、主要性能指标的测试结果,提出了改善其性能的途径。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

18.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

19.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

20.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

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