Component Fatigue Behaviors And Life Predictions Of A Steering Knuckle Using Finite Element Analysis
The paper describes a vehicle steering knuckle undergoing time-varying loadings during its service life. Fatigue behavior is, therefore, a key consideration in its design and performance evaluation. This paper is aimed to assess fatigue life and compare fatigue performance of steering knuckles made from three materials of different manufacturing processes. These include forged steel, cast aluminum, and cast iron knuckles. In light of the high volume of forged steel vehicle components, the forging process was considered as base for investigation. Static as well as baseline cyclic deformation and fatigue properties were obtained and compared. The paper envisages that in addition, referring a number of load-controlled fatigue component tests conducted for the forged steel and cast aluminum knuckles. Finite element models of the steering knuckles were also analyzed to obtain stress distributions in each component. Based on the results of component testing and finite element analysis, fatigue behaviors of the three materials and manufacturing processes are then compared. The paper concludes with that forged steel knuckle exhibits superior fatigue behavior, compared to the cast iron and cast aluminum knuckles.
Fatigue Analysis of Automative Steering Knucle
Steering knuckle plays a vital role in automobile which connects the suspension, steering part, wheel hub and brake to the chassis. During its working, it subjected to various loading conditions. so, it requires high accuracy,, quality, and durability. The main theme of this work is to access the fatigue performance of a steering knuckle. This can be performed by a detailed load analysis. Therefore, this study requires two steps. First part of the study involves modeling of the steering knuckle with the design parameters using the latest modeling software CATIA and the second part involves in fatigue analysis using ANSYS WORKBENCH. This provides us to improve the overall knowledge about the component.
Mechanism of the depressor response to dopamine in the rat treated with phenoxybenzamine.
Alterations of hypotensive responses to dopamine by antagonists were characterized in alpha-blocked, anaesthetized rats. Responses were not affected by d-propranolol (0.1 mg/kg) whereas d,1-propranolol (0.1 mg/kg) or haloperidol (1.0 mg/kg) attenuated them; higher doses of inhibitors (1.0 mg/kg; 5.0 mg/kg, respectively) failed to produce a higher inhibition, but combinations of low doses abolished the depressor responses. In adrenalectomized rats, hypotensive responses decreased; haloperidol always attenuated the responses while d,1-propranolol became ineffective. Dopamine produced an enhancement of plasma adrenaline and noradrenaline levels, which was decreased by d,1-propranolol and increased by haloperidol. The data suggest that in rats the depressor component of dopamine is due to activation of both dopaminergic and beta-adrenoceptors. The beta component appears to be due to the release of adrenaline. The results also support the concept of the existence in sympathetic nerve endings and adrenal glands of stimulatory beta-adrenergic and inhibitory dopaminergic prejunctional receptors.