Effect of Temperature Variation on Oil in Oscillation of Mass/Load

In this investigation a model was made to replicate the working of a shock absorber and the liquid that is used in place of the hydraulic fluid was vegetable oil. Hydraulic fluid is composed of a mineral oil base stock [1]. The working of the model of a shock absorber was tested at different temperatures. It is studied that the relation between the temperature and the time taken by the load attached to the spring to stop oscillating and presented in graph. An optimum temperature, at which the time taken by the mass of 1.50 kilograms suspended in the vegetable oil to stop oscillating and it is the least mass used in the study. In addition to this, the freezing point of the vegetable oil will also be found. It is found in this study that the two variables that is temperature of the vegetable oil and the mass of 1.5 kilograms at rest is linear. Keywords: Temperature Variation, Oil, Oscillation, Mass, Load.

Energy analysis of transfer processes and their main characteristics in thermo mechanical damping systems

The article discusses the energy analysis of transfer processes in the damping system. The basic theoretical foundations based on the equations of the energy balance of the hydraulic shock absorber and the law of conservation of energy are presented. The proposed approach is associated with the development of a methodology and scheme for calculating the technical system of vibration damping. The schemes of interaction of the system through the phenomena of transfer and functioning of the vibration protection system with the environment are presented. It is shown that damper systems are based on the physical process of transformation of mechanical energy into thermal energy with subsequent dissipation into the environment. The total energy distribution in damping problems takes the following form the mechanical energy of motion is absorbed due to the hydraulic resistance of the liquid and turns into a dissipative component, which can reach 80% of the total energy. A mathematical model of the law of conservation of energy is presented which includes a dissipative function. The analysis of how it is possible to design work processes in a shock absorber due to energy dissipation and similarity criteria: Euler, Froude, Reynolds, etc. As a result of physical experiments, it was found that the movement of a fluid in hydraulic calibrated throttles gives rise to cavitation and various physical phenomena and accompanying processes, in which there is a significant change in the energy balance and energy dissipation in non-stationary modes of fluid movement. The dependence of the total power loss of the shock absorber under changing operating conditions, and the diagram of physical processes and energy transformations in the problems of damping, which are in dissipative processes, are given. The article describes the principles that can be used for the design of devices and modules of damper systems of a wide class with the possibility of energy recovery and accumulation by introducing a damper into the system, for example, a motor generator, an inductor with permanent magnets or a peso element in the design of a traditional telescopic shock absorber.

Infectious Causes of Acute and Chronic Sinusitis

Paranasal sinuses anatomy is paired in 4 parts which includes frontal, maxillary, ethmoid, and sphenoid. Their relevant function is to secrete mucous for moisture, humidify inspired air, impart vocal resonance, and act as shock absorber for intracranial contents. Retention of secretions in the nasal cavity and sinuses can cause inflammation of the mucosa of paranasal sinuses and lead to infection. Classification of sinusitis is based on duration of symptoms. Diagnosis can be achieved clinically, however other diagnosis modalities such as cultures or radiology can help to achieve accurate diagnosis. Depending on the etiology management can be supportive or pharmacological. In some cases, long term monitoring and prevention therapy may be required.

PROSPECTIVE ELECTROMECHANICAL SHOCK ABSORBERS

The article considers the issue of the system of the running gear of a high-speed electric train with a body inclination and the system of oscillation recovery. The authors considered the main suspension systems of the electric train body, which are currently used. The main problems of these suspension systems were put forward. Attention is paid to the use of air-spring suspension. The pipe suspension of the VL80 electric locomotive and the construction of the trolley itself are considered. The basic criteria of an estimation of efficiency of perspective electromechanical shock-absorbers on which the comparative characteristic is carried out are defined. The article describes a promising electromechanical shock absorber based on a synchronous linear motor, which can provide both body tilt and damping and recovery of oscillations. The functional scheme of control of two synchronous linear motors which are established on one cart is considered. The operation of the control system of synchronous linear motors is described. The design of a linear DC motor with permanent magnets is described. The functional control scheme of two linear DC motors with permanent magnets is considered. The design of the electromechanical shock-absorber of the Bose company is resulted. The comparative characteristic of three perspective electromechanical shock-absorbers on six criteria is carried out. Conclusions are made and an electromechanical shock absorber is selected, which provides the basic needs of rolling stock.

Study of Suspension Parameters Matching to Enhance Vehicle Ride Comfort on Bump Road

In this study, the parameters of the MacPherson front suspension and the E-type multilink rear suspension are matched to enhance the vehicle ride comfort on bump road. Vehicle vibration and suspension stiffness are analyzed theoretically. In the simulation study, the influence of the front and rear wheels on the vehicle vibration is considered, so the time-domain curves of the front and rear seat rail accelerations are processed by adding windows with two different window functions. The resulting ΔRmsLocal and ΔRmsGlobal are used as evaluation indexes of the vehicle ride comfort. The sensitivity analysis yields the magnitude of the influence of the suspension parameters on the evaluation indexes. In addition, the trends of ΔRmsLocal and ΔRmsGlobal with bushing stiffness at different vehicle speeds are discussed. The results show that longitudinal ΔRmsLocal and ΔRmsGlobal of the seat rails are influenced by the bushings mostly, while the vertical ΔRmsLocal and ΔRmsGlobal of the seat rails are influenced by the spring and shock absorber mostly. The trends of ΔRmsLocal and ΔRmsGlobal with bushing stiffness are influenced by the speed of the vehicle. Finally, the vehicle ride comfort is enhanced after optimization and matching of the suspension parameters by NSGA-II optimization algorithm.

AMR Sign: A Clinical Sign of Mechanical Integrity of Medial Meniscus

Introduction:Meniscus injury is now widely being diagnosed and managed. Meniscus acts as a shock absorber and transmits forces from femur to tibia. However, if the meniscus is torn, the hoop strength is lost. In hidden meniscus injuries, budding arthroscopy surgeons tend to miss the tear. AMR sign acts as a light-bearer for identifying the breach in the collagen architecture. Methods and Materials: 267 patients were included in the study. Informed written consent was taken from all the patients operated and included in the study. Following a fixed protocol of diagnostic arthroscopy, documentation of AMR sign and its relation with intactness of the medial meniscus was done. If medial meniscus tear was found, after repair, its relation with AMR sign was documented.