Failure Investigation Report on Different Components of an Automotive Engine
This paper presents an investigation report of different components failure which affect the performance of an automobile engine. The premature breakage of a four cylinder diesel engine block, crankshaft, camshaft, crankshaft bearing, camshaft bush, engine oil pump was reported. It is found that the failure of each component having the same reason for its failure as reported from different place. Thus it affected the performance of the vehicle and it is very expensive for the customer to replace the damaged parts for several times. In this paper, we presented detailed analysis of the causes for the failure along with preventive suggestion to maintain the engine for better performance.
Dynamic analysis of loads and stresses in connecting rods
Abstract Automobile internal combustion engine connecting rod is a high volume production component subjected to complex loading. Proper optimization of this component, which is critical to the engine fuel efficiency and more vigorously pursued by the automotive industry in recent years, necessitates a detailed understanding of the applied loads and resulting stresses under in-service conditions. In this study, detailed load analysis under service loading conditions was performed for a typical connecting rod, followed by quasi-dynamic finite element analysis (FEA) to capture stress variations over a cycle of operation. On the basis of the resulting stress-time histories, variation of stress ratio, presence of mean and bending stresses, and multi-axiality of stress states in various locations of the connecting rod under service operating conditions were investigated. It was found that even though connecting rods are typically tested and analyzed under axial loading and stress state, bending stresses are significant and a multiaxial stress state exists at the critical regions of connecting rod. A comparison is also made between stresses obtained using static FEA which is commonly performed and stresses using quasi-dynamic FEA. It is shown that considerable differences in obtained stresses exist between the two sets of analyses.
Expansion without equity: An analysis of current policy on access to higher education in Brazil
Access to higher education in Brazil is to a large extent restricted to the higher socio-economic groups. Public universities have limited places and entry is determined by highly competitive exams, thereby excluding those who have not had a high quality secondary education or attended an expensive preparatory course. There has been considerable growth in the private sector to absorb the excess demand, but the majority of Brazilians cannot afford the fees. This paper develops a concept of equity in higher education in which, firstly, there should be sufficient places in the system as a whole and, secondly, all people should have a fair opportunity of attending the university of their choice regardless of socio-economic background. Recent efforts to expand access are analysed, including incentives for the growth of private universities, student loans and the new Prouni initiative, in which private institutions provide free places to low-income students in return for tax exemptions. While these initiatives have the potential to increase the total number of places, they will not lead to an equitable expansion, as disadvantaged students will still be confined to courses of lower quality or with lower subsequent value on the employment market. Initiatives aimed at the public sector such as the introduction of quotas and changes to entry examinations are also discussed. Finally, some implications for future policy development are outlined.