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The hip joint helps the upper body to transfer its weight to lower body. Along with age, there are various reasons for the degeneration of the hip joint. The artificial hip implant replaces the degenerated hip. Wear between the joints is the primary cause of the hip implant becoming loose. The wear can occur due to various reasons. Due to this revision surgery are most common in young and active patients. In the design phase of the implant if this is taken care then life expectancy of the implant can be improved. Small design changes can significantly enhance the implant’s life. In this work, elliptical-shaped hip implant stem is designed, and linear wear is estimated at trunnion junction. In this work, a 28 mm diameter femoral head with a 4 mm thick acetabular cup and a 2 mm thick backing cup is used. The top surface taper radiuses are changed. Solid works was used to create the models. Ansys was used to perform the analysis. It was found that as the radius of the TTR decreased, the wear rate decreased. The least wear rate was found in 12/14 mm taper with a value of 1.15E−02 mm year−1 for the first material combination and with a value of 1.23E −02 mm year−1 for the second material combination. In the comparison between the models with 1 mm chamfer and no chamfer, it was found that the wear rate was lower for the models with 1 mm chamfer. When the chamfer was increased (more than 1 mm), the linear wear increased. Wear is the main reason for the loosening of hip implants, which leads to a revision of an implant. It was found that with a decrease in TTR, there was a small increase in the linear wear rate. Overall, the implant with TTR 6 mm and a chamfer of 1 mm was found to have the least wear rate. To validate these results, the implant can be 3D printed and tested on a hip simulator.

The lateral deviation of the cricket ball, often named as ‘Swing’, is one of the most complex phenomena in the sport of cricket. As the ball proceeds through the flight path, the interaction between the ball surface and flow field causes a deviation for the ball from the initial path, resulting in a modified curved path. Several experimental tests have been conducted to study the parameters which cause the ‘swing’ phenomenon, in order to improve and optimize the performance of the cricket ball. A seam is a governing factor for the magnitude of swing. This is attributed to the considerable difference in the pressure acting on the seam and non-seam side of the ball which, consequently, produces the side force. In this work, a computational fluid dynamic modeling for the cricket ball in the flow field has been carried out. The Flow field at 0° and 20° seam angles and four bowling velocities of 5, 25, 29, and 36.5 m/s have been computationally analyzed. The pressure difference across the ball at 0° seam angle has no significant effect for producing any observable swing. The maximum pressure difference was achieved at the velocity of 29 m/s, and, generally, the speed above 30 m/s does not affect the swing. As the flow velocity increases above 30m/s, asymmetric pressure distribution can be noticed but with a negligible effect as in the lower velocities. Thus, the optimum swing can be obtained only at velocities below 30 m/s.

Objective: Low-level laser therapy (also known as photobiomodulation therapy, PBMT) promotes accelerated healing of diabetic foot ulcers (DFUs), thereby preventing the risk of future complications and amputation. The aim of this study was to determine the effect of PBMT, with structured, graded mobilisation and foot care, on DFU healing dynamics. Method: Patients diagnosed with type 2 diabetes, diabetic peripheral neuropathy and presenting with a chronic neuroischaemic DFU, were treated with PBMT using scanning and non-contact probe methods. The DFU was clinically observed and the area measured every seven days until complete healing. Neuropathic parameters were also measured. The PBMT was administered until complete closure of the DFU and patients also undertook a programme of graded mobilisation. Results: A total of 17 participants were recruited, with a mean age of 69±8 years, and a mean duration of diabetes of 13±5 years. Mean complete closure time was 26±11days. In addition, a mean reduction of the semi-quantitative vibration pressure threshold from 49±2 volts to 20±4 volts was observed in all participants. Conclusion: PBMT can be effectively used as a treatment mode for neuroischaemic DFUs in patients with type 2 diabetes. Graded mobilisation with focused foot care could improve the function of people living with type 2 diabetes with a chronic DFU.

Background and objective The bladder receives the urine from the kidney and ureter. The series of peristaltic waves facilitate urine transport to the bladder. The peristaltic flow in the ureter is associated with fluid trapping and material reflux, which may cause an increase in bladder pressure. It is difficult to visualize the complex peristalsis phenomenon, in the ureter using image and radiography experiments. A numerical simulation will help in the understanding of urine bolus formation and its effect on the ureter wall. Methods A three-dimensional computational fluid dynamic analysis is carried out to understand the flow physics associated with bolus formation and the effect of reflux on the ureter. ANSYS-CFX, a commercially available computational dynamics package is used to simulate the peristalsis. A single sinusoidal peristaltic wave traveling along a circular tube will yield the velocity, pressure, wall shear stress distributions inside the ureter. Results The propagation of the peristaltic wave results in the backflow of urine near the inlet at the beginning of the flow. As the wave propagates towards the outlet, the flow rate decreases. It is observed that pressure distribution along the ureter axis will deteriorate towards the outlet. The contraction produces a very high-pressure gradient which causes the urine backflow. The trapping and the bolus formation cause a significant rise in bolus pressure, simultaneously developing negative pressure at the contraction neck. Conclusions The effect of peristalsis on the ureter biofluid dynamic behavior of the ureter is visualized in this study. It is established that the peristaltic contraction results in high-pressure formation at the bolus and negative pressure at the neck. It was found to be a maximum of 1.1 Pa at the bolus center and —1.13 Pa at the neck region. At the ureter pelvis junction, a higher wall shear of 0.095 Pa is observed as the wave starts to propagate. The velocity vectors show that the trapping of urine causes reflux and results in an adverse pressure gradient near the wall. A maximum pressure gradient of 485 Pa/meter was observed at the contraction of the ureter wall.

Due to intrinsic or extrinsic conditions, the number of car accidents has increased currently across the globe. Drivers must be assured that they can avoid these problematic conditions. According to the statistics, about 10,000 are dead, and more than a million people are wounded each year in India. Hence, improvement in the safety of vehicles is of utmost importance to shoot down the number of accidents. The automotive bumper beam is one of the essential components in passenger cars. Bumper beams reduce or minimize the extent of impact caused at the front and rear ends during a collision in passenger vehicles. It absorbs the impact energy. The important physical parameters in the bumper beams such as material, size, and design to improve the extent of crashworthiness are studied and discussed in this current work. Comparative analysis between 2 mm thickness and 4 mm thickness bumper with honeycomb structure is studied. An ideal design composition is considered. This helps in advanced safety precautions.

In present day, the application of low cost material reinforced metal alloy is growing rapidly in different engineering fields [1]. The present study shows the possibilities of reinforcing Al 6061 alloy with conventionally prepared charcoal by using bamboo. The bamboo for the preparation of charcoal is initially divided into wet and dry samples. The wet samples are directly used after cutting from tree for the preparation of charcoal out of it and dry sample it is dried for 7days after cutting then used for preparation. The carbon content in both the samples is analysed by proximity analysis and elemental analysis by EDS (energy dispersive spectroscopy technique)[2]. Fine particles of bamboo charcoal of 2%, 4%, and 6% by weight were used to prepare the alloy by stir casting method. The fabricated alloys with different weight composition is normalized in 5500C for 6 hours and followed by different cooling techniques. The hardness and tensile properties were studied. It is found that the hardness of the Aluminium 6061 is going to be increased with increased in the concentration of bamboo charcoal and the tensile strength is going to be decreased with increased in the concentration of bamboo charcoal

Bio fiber based composite materials are gaining interest in the field of certain engineering applications because of their easy processing, low cost, low density and higher strength to weight ratio. In the present study, randomly oriented short Areca Husk and Coir fibers were reinforced with unsaturated polyester resin for the fabrication of composites. The fibers were pretreated with sodium hydroxide to enhance the interphase bonding between the fibers and matrix material. Specimens were prepared and tested for tensile strength, flexural, hardness and impact strength as per respective ASTM standards. The results revealed that individual areca husk fiber reinforced specimens shows improved performance in all properties over coir fiber reinforced specimens. However the hybrid composite specimens test results shows average values as compared to individual fiber reinforced composites.

Background and objective Finite element based simulation has emerged as a powerful tool to analyse the tooth strength and its fracture characteristics. The aim of this study is to compare and evaluate the fracture resistance of immature teeth reinforcement with MTA, Biodentine and Bioaggregate as an apical plug and backfill material using Finite Element Method. Methods A 3D finite element analysis model was generated using a simulated immature maxillary central incisor. Seven different models were developed representing (Model 1): control group having an immature tooth model without any reinforcement material; (Model 2): Mineral trioxide aggregate (MTA) as apical plug 4 mm; (Model 3): Biodentine as apical plug 4 mm; (Model 4): Bioaggregate as apical plug 4 mm; (Model 5): MTA filled in the entire root canal 8.5 mm; (Model 6): Biodentine filled in the entire root canal 8.5 mm; (Model 7): Bioaggregate filled in the entire root canal 8.5 mm. A force of 100 N was applied at an angle of 130° to the palatal surface of the tooth. Stress distribution at cemento‑enamel junction was measured using the Von Mises stress criteria. Results It was found that the 4 mm apical plug using MTA showed higher fracture resistance when compared to 8.5 mm backfill using MTA. When MTA was replaced as backfill material by Biodentine and Bioaggregate, the von mises stress increased by 64% and 94% respectively. Conclusions It is not desirable to restore the entire root canal of an immature teeth using same material due to higher stress concentration at the cervical region. Considering the shorter setting time and improved handling characteristics, Biodentine can be preferred over the time‑tested MTA as an apical plug.

In this work, a 3D urinary bladder was subjected to various pressure loading conditions mimicking the bladder filling volume. The bladder layer consisting of adventitia, detrusor and mucosa layer having different mechanical properties produced different deformation and stresses when subjected to the varying loads. The volume of the bladder changed to 231.34[Formula: see text]ml which was 128.91% higher than the assumed initial volume of 50[Formula: see text]ml on application of 18[Formula: see text]kPa of pressure. The detrusor layer which is thickest of the bladder wall reduced to 1.312[Formula: see text]mm from 4.4[Formula: see text]mm, recording a 108% change in its thickness at 18[Formula: see text]kPa pressure. The maximum von-Mises stress obtained were significantly higher in case of the Mucosa layer when compared to the detrusor and adventia layer. The unique layup of the bladder wall having different properties plays a major role in sustaining adverse pressure gradients and absorbing high stresses.

Smart materials are materials, which have a definite response to stimulus provided through a change in pressure, temperature and termed as shape memory alloys (SMA). In this review, the general concept of SMA’s has been discussed along with shape memory effects. Shape memory material properties depend on phase shifting phenomena, which consist of pseudoelasticity and thermoelasticity. The basic SMA such as Ni-Ti (Nickel-Titanium) alloys, Copper (Cu) based SMA, Iron (Fe) based SMA are commonly used in the industry, Ni-Ti alloys are expensive but it has good super elasticity and superior mechanical properties. Cu and Fe based are economical as compared to the Ni-Ti alloys. The various fabrication techniques and common composition of the alloys have been discussed with in detail.

Metal matrix composites (MMCs) have a wide scope of industrial applications and triumph over conventional materials due to their light weight, higher specific strength, good wear resistance and lower coefficient of thermal expansion. The present study aims at establishing the feasibility of using Bamboo charcoal particulate and boron carbide as reinforcements in Al-6061 alloy matrix and to investigate their effect on the wear of composites taking into consideration the interfacial adhesion of the reinforcements in the alloy. Al-6061 alloy was chosen as a base metallic alloy matrix. Sun-dried bamboo canes were used for charcoal preparation with the aid of a muffle furnace. The carbon content in the charcoal samples was determined by EDS (energy dispersive spectroscopy). In present study, stir casting technique was used to prepare the samples with 1%, 2%, and 3% weight of bamboo charcoal and boron carbide with Al-6061. The fabricated composites were homogenised at 570°C for 6 hours and cooled at room temperature. Wear studies were carried out on the specimens with different speed and loads. It was found that wear rate and coefficient of friction decreased with increase in the reinforcement content.

This paper presents simulation and analysis of machining of elastomers under cryogenic condition using finite element method. The inelastic-plastic finite element technique is established in this learning to examine the consequence of the single point cutting tool rake angle on the chip flow and cutting force developed in machined work piece during the orthogonal turning process of elastomer. The findings designate that an intensification in the tool rake angle leads to decrease in the cutting force developed and continuous and smoother chip contour during machining elastomer