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Background Two-wheeled vehicles are the major mode of transportation in India. Such vehicles are exposed to excessive vibration on the road when compared to four-wheeled vehicles. However, the research on the reduction of whole body vibration in the case of two-wheelers is not explored in detail. The present study predicts rider comfort in the case of an electric two-wheeler as per ISO 2631-1, by obtaining the finding the weighted acceleration at the strategic locations of vibration at the test rig. Methods An electric two-wheeler test rig is used in the study. The values of acceleration from the test rig in running conditions are obtained by using NI LabVIEW 2019. The drive cycle of the electric vehicle (EV) test rig is controlled by Sync sols’ EV lab software. Obtaining the weighted root mean square (RMS) acceleration from running the test setup, it is compared with the ISO 2631-1 standard to obtain the rider comfort. Results Loading area, traction motor, base mount, and suspension were found to be the strategic points of vibration. Frequency weighted RMS acceleration of 0.3 to 0.4 m/s 2 obtained at these points are prone to cause discomfort for the rider. Vehicle speed, road profile, and duration of exposure were found to be important parameters affecting the rider’s comfort. A maximum of 4.6 m/s 2 amplitude was observed. The loading area, which corresponds to a rider’s seat in actual vehicle, is important and reduction of these vibrations make the ride comfortable for the rider. Suspension and base mount of the test rig are found to be uncomfortable observing the weighted RMS acceleration. Conclusions A suitable damping technique design is very much essential in reducing these vibrations and improve the rider comfort, as many more non-deterministic vibrations are prone to cause dis-comfort in case of actual on road riding conditions.

In this study, the crashworthiness analysis of filled and unfilled bumper beams in head-on collisions was carried out through finite element simulations. The beam design was based on popular SUV brands in India. The outer bumper or fascia was made of AA6061-T6. Various advanced filler materials, including expanded polypropylene foam (cellular), pure PM aluminum foam (cellular), carbon fiber/epoxy (fiber-reinforced composite), and glass fiber-reinforced polymer (fiber-reinforced composite), were used to fill the inner bumper beam section. Based on the type of filler for the inner bumper section, the various configurations were given a nomenclature of C-I (Unfilled), C-II (Pure powder metallurgy aluminium foam), C-III (Expanded polypropylene foam), C-IV (Carbon fiber reinforced fiber), C-V (Glass fiber reinforced polymer). Numerical simulations were conducted using Ansys Explicit Dynamics ® software. The results indicated that EPP foam-filled bumpers (C-III) performed best in terms of crashworthiness, offering both lightweight properties and effective energy absorption. CFRP-filled bumpers (C-IV) showed the next best performance, showing high energy absorption, and the highest von Mises equivalent strain among the filler materials. PM aluminum foam-filled bumpers (C-II) demonstrated improved total energy absorption compared to unfilled bumpers, whereas GFRP-filled bumpers (C-V) exhibited poor crashworthiness characteristics.

Considering the current growth of design and development activities in micro/mini-Unmanned Aerial Vehicles (UAVs), there is a significant need for thin, durable and lightweight composites for their structural applications. Robust and impact-resistant materials are deemed mandatory concerning the harsh operational conditions where these UAVs are employed. Numerical models for composite materials at various loading conditions can bring up tremendous pace in various design and manufacturing aspects of such competent and tailored engineering materials. Numerical simulations of low velocity flatwise Charpy impact are performed on carbon/aramid hybrid laminates. The modelling is based on representative volume element (RVE) micro-scale property homogenisation in ANSYS Workbench, followed by macroscale impact analysis in ABAQUS/EXPLICIT. The damage propagation was determined using the Hashin failure criteria. The numerically predicted results were validated against the experimental data concerning the energy absorbed and impact strength. The results provided by the modelling are in good correlation with the experimental observations. The numerically obtained force-time data correlated the damage propagation and failure modes observed in the post-impact damage morphology in the laminate during the non-instrumented Charpy test.

Background Two-wheeled vehicles are the major mode of transportation in India. Such vehicles are exposed to excessive vibration on the road when compared to four-wheeled vehicles. However, the research on the reduction of whole body vibration in the case of two-wheelers is not explored in detail. The present study predicts rider comfort in the case of an electric two-wheeler as per ISO 2631-1, by obtaining the finding the weighted acceleration at the strategic locations of vibration at the test rig. Methods An electric two-wheeler test rig is used in the study. The values of acceleration from the test rig in running conditions are obtained by using NI LabVIEW 2019. The drive cycle of the electric vehicle (EV) test rig is controlled by Sync sols’ EV lab software. Obtaining the weighted root mean square (RMS) acceleration from running the test setup, it is compared with the ISO 2631-1 standard to obtain the rider comfort. Results Loading area, traction motor, base mount, and suspension were found to be the strategic points of vibration. Frequency weighted RMS acceleration of 0.3 to 0.4 m/s2 obtained at these points are prone to cause discomfort for the rider. Vehicle speed, road profile, and duration of exposure were found to be important parameters affecting the rider’s comfort. A maximum of 4.6 m/s2 amplitude was observed. The loading area, which corresponds to a rider’s seat in actual vehicle, is important and reduction of these vibrations make the ride comfortable for the rider. Suspension and base mount of the test rig are found to be uncomfortable observing the weighted RMS acceleration. Conclusions A suitable damping technique design is very much essential in reducing these vibrations and improve the rider comfort, as many more non-deterministic vibrations are prone to cause dis-comfort in case of actual on road riding conditions.

Kidney stones, known medically as nephrolithiasis, present a significant health concern globally, particularly in regions such as India and the Middle East. Despite extensive research, the complexity of ureteral obstruction due to kidney stones remains a challenge in urology. This study addresses this gap by analysing the effects of obstruction in a three-dimensional model of the ureter with a constant diameter, simulating various percentages of blockage. Through computational analysis, the pressure and velocity effects on the ureter wall are explored, providing insights into the dynamics of obstructed ureters. Building upon previous research, this study contributes to a deeper understanding of the factors influencing flow patterns and pressure variations within the urinary tract. Additionally, findings from this study may lead to advancements in non-invasive assessment methods for diagnosing and treating ureteral obstruction caused by kidney stones. Furthermore, insights gained from this research could potentially inform clinical decision-making, leading to improved management strategies and better outcomes for patients affected by this debilitating condition. The novelty of this work lies in its comprehensive analysis of the effects of obstruction on the ureteral wall, offering valuable implications for urological practice and patient care.

Background Two-wheeled vehicles are the major mode of transportation in India. Such vehicles are exposed to excessive vibration on the road when compared to four-wheeled vehicles. However, the research on the reduction of whole body vibration in the case of two-wheelers is not explored in detail. The present study predicts rider comfort in the case of an electric two-wheeler as per ISO 2631-1, by obtaining the finding the weighted acceleration at the strategic locations of vibration at the test rig. Methods An electric two-wheeler test rig is used in the study. The values of acceleration from the test rig in running conditions are obtained by using NI LabVIEW 2019. The drive cycle of the electric vehicle (EV) test rig is controlled by Sync sols’ EV lab software. Obtaining the weighted root mean square (RMS) acceleration from running the test setup, it is compared with the ISO 2631-1 standard to obtain the rider comfort. Results Loading area, traction motor, base mount, and suspension were found to be the strategic points of vibration. Frequency weighted RMS acceleration of 0.3 to 0.4 m/s 2 obtained at these points are prone to cause discomfort for the rider. Vehicle speed, road profile, and duration of exposure were found to be important parameters affecting the rider’s comfort. A maximum of 4.6 m/s 2 amplitude was observed. The loading area, which corresponds to a rider’s seat in actual vehicle, is important and reduction of these vibrations make the ride comfortable for the rider. Suspension and base mount of the test rig are found to be uncomfortable observing the weighted RMS acceleration. Conclusions A suitable damping technique design is very much essential in reducing these vibrations and improve the rider comfort, as many more non-deterministic vibrations are prone to cause dis-comfort in case of actual on road riding conditions.

Background Two-wheeled vehicles are the major mode of transportation in India. Such vehicles are exposed to excessive vibration on the road when compared to four-wheeled vehicles. However, the research on the reduction of whole body vibration in the case of two-wheelers is not explored in detail. The present study predicts rider comfort in the case of an electric two-wheeler as per ISO 2631-1, by obtaining the finding the weighted acceleration at the strategic locations of vibration at the test rig. Methods An electric two-wheeler test rig is used in the study. The values of acceleration from the test rig in running conditions are obtained by using NI LabVIEW 2019. The drive cycle of the electric vehicle (EV) test rig is controlled by Sync sols’ EV lab software. Obtaining the weighted root mean square (RMS) acceleration from running the test setup, it is compared with the ISO 2631-1 standard to obtain the rider comfort. Results Loading area, traction motor, base mount, and suspension were found to be the strategic points of vibration. Frequency weighted RMS acceleration of 0.3 to 0.4 m/s2 obtained at these points are prone to cause discomfort for the rider. Vehicle speed, road profile, and duration of exposure were found to be important parameters affecting the rider’s comfort. A maximum of 4.6 m/s2 amplitude was observed. The loading area, which corresponds to a rider’s seat in actual vehicle, is important and reduction of these vibrations make the ride comfortable for the rider. Suspension and base mount of the test rig are found to be uncomfortable observing the weighted RMS acceleration. Conclusions A suitable damping technique design is very much essential in reducing these vibrations and improve the rider comfort, as many more non-deterministic vibrations are prone to cause dis-comfort in case of actual on road riding conditions.

AbstractThe hip joint is one of the most essential joints for transmitting weights to the lower abdomen during day-to-day activities. Loosening of hip implants is mostly caused by wear. The wear assessment during the design stage offers a clear sense of the implant’s life expectancy, and modest adjustments in the design may also greatly enhance the implant’s life expectancy, lowering the probability of revision surgery. Linear wear is estimated at the contact surfaces of the femoral head to the acetabular cup and the acetabular cup to the backing cup in this study. In this work, oval-shaped hip implant is considered with a femoral head diameter of 28 mm, an acetabular cup thickness of 4 mm, and a backing cup thickness of 2 mm. The Archard’s law used to estimate the linear wear rate. It is observed that when the acetabular cup is made of UHWMPE and the stem, femoral head, and backing cup are made of CoCr, the least overall deformation is 0.394 mm during walking loads. When the stem is considered Ti−6Al−4 V and the acetabular cup of UHWMPE, the minimum wear between the femoral head and acetabular cup is 0.063 mm/year. During a typical standing posture, an acetabular cup-to-backing cup wear rate of 0.007 mm/year is estimated. Overall, the CoCr material combination had the lowest wear rate in the four activities considered for this work. These implants designs can be 3D-printed and further can be tested in a hip simulator under the same loading conditions.

Background: Two-wheeled vehicles are the major mode of transportation in India. Such vehicles are exposed to excessive vibration on the road when compared to four-wheeled vehicles. However, the research on the reduction of whole body vibration in the case of two-wheelers is not explored in detail. The present study predicts rider comfort in the case of an electric two-wheeler as per ISO 2631-1. Methods: An electric two-wheeler test rig is used in the study. The values of acceleration from the test rig in running conditions are obtained by using NI LabVIEW 2016. The drive cycle of the electric vehicle (EV) test rig is controlled by Sync sols’ EV lab software. Obtaining the root mean square (RMS) acceleration from running the test setup, it is compared with the ISO 2631 standard to obtain the rider comfort. Results: Loading area, traction motor, base mount, and suspension were found to be the strategic points of vibration. RMS acceleration of 0.2 g to 3.29 g obtained at these points are prone to cause discomfort for the rider. Vehicle speed, road profile, and duration of exposure were found to be important parameters affecting the rider’s comfort. A maximum of 3.28 g amplitude was observed at the loading area at no load condition. The loading area, which corresponds to a rider’s seat in actual vehicle, is important and reduction of these vibrations make the ride comfortable for the rider. Suspension and base mount of the test rig are found to be uncomfortable observing the RMS acceleration. Conclusions: A suitable damping technique design is very much essential in reducing these vibrations and improve the rider comfort, as many more non-deterministic vibrations are prone to cause dis-comfort in case of actual on road riding conditions.

In recent years, there has been a significant increase in the use of natural fibers as reinforcements in composites. This trend is mainly driven by their eco-friendly nature and wide availability. The objective of this research is to explore the extensive potential of combining Banana Fiber with Tyre Rubber Particles (TRP) as elastomeric fillers in natural fiber composites, focusing primarily on their applications in the automotive and aeronautical industries, particularly in terms of acoustic response. The composite sequences were named as NFC-I to NFC-V, where NFC represented Natural Fiber Composites. To thoroughly investigate the acoustic properties of these innovative composites, experimental analysis on the impedance tube was conducted along with numerical simulations on the Ansys Harmonic Acoustics ^® module with Transmission Loss (TL) as the key parameter. An orthotropic material model based on the chopped fiber RVE (Representative Volume Element) was developed on the Ansys 2022 R1 ^® Material Designer Module which could be deemed as the novelty of the current work. From the results, it was seen that within the designated frequency bands, specifically the low (67–400 Hz), medium (400–1900 Hz), and high (1900–6300 Hz) ranges, the NFC-4 (15 wt% of TRP) composite consistently demonstrated the lowest average TL values. Conversely, NFC-3 (27 wt% of TRP) consistently showcased the highest TL values, reaching a peak of 27.13 dB in the low-frequency range and 46.73 dB in the high-frequency range. The results obtained from the impedance tube experiments align remarkably well with the numerical simulation outputs, demonstrating the reliability of the numerical model in estimating the transmission loss of composite laminatesa crucial parameter for evaluating acoustic performance.

Background: Two-wheeled vehicles are the major mode of transportation in India. Such vehicles are exposed to excessive vibration on the road when compared to four-wheeled vehicles. However, the research on the reduction of whole body vibration in the case of two-wheelers is not explored in detail. The present study predicts rider comfort in the case of an electric two-wheeler as per ISO 2631-1. Methods: An electric two-wheeler test rig is used in the study. The values of acceleration from the test rig in running conditions are obtained by using NI LabVIEW 2016. The drive cycle of the electric vehicle (EV) test rig is controlled by Sync sols’ EV lab software. Obtaining the root mean square (RMS) acceleration from running the test setup, it is compared with the ISO 2631 standard to obtain the rider comfort. Results: Loading area, traction motor, base mount, and suspension were found to be the strategic points of vibration. RMS acceleration of 0.2 g to 3.29 g obtained at these points are prone to cause discomfort for the rider. Vehicle speed, road profile, and duration of exposure were found to be important parameters affecting the rider’s comfort. About 19 % increase in the vibration amplitude is observed at the loading area when loads are removed. The loading area as corresponds to a rider’s seat in actual vehicle, it is important to reduce these vibrations to make the ride comfortable for the rider. Conclusions: A suitable damping technique design is very much essential in reducing these vibrations and improve the rider comfort, as many more non-deterministic vibrations are prone to cause dis-comfort in case of actual on road riding conditions.

The human nasal cavity develops from birth with size anatomical changes. This study aims to evaluate the flow parameters and particle deposition parameters. Neonatal and infant nasal cavities are developed using MIMICS 21.0, and the flow is evaluated by ANSYS 2021 R2 using CFD to evaluate velocity, pressure, micro- and nanoparticle depositions under sedentary breathing conditions. Neonatal nasal valve velocity was recorded 3.5 times higher compared to the infant for 1.8 LPM and 2.7 times for 3 LPM. Neonatal vestibular depositions up to 10 µm were 6.6%, which increased to 76% for 60 µm for 1.8 LPM and increased to 21.3% for 10 µm and 79% for 60 µm for 1.8 LPM. The neonatal nasal valve showed maximum depositions of around 35% for 20 µm for both flow rates. Maximum depositions of nanoparticles are in the mid-nasal region. Infant nasal cavities deposit around 1% to 2% for nanoparticles below 20 nm for both flow rates. Neonatal overall microparticle depositions doubled with an increase in flow rate up to 10 µm. The overall deposition efficiency of nanoparticles increases 1.5 times with increasing flow rate. This study will help with the medical administration of aerosol-based medications in the patient and age-specific nasal cavity. [ABSTRACT FROM AUTHOR]

In replacement surgery of the hip joint, an implant is replaced into the natural femur which recreates the articulation and functionally of a natural joint. Total hip replacement is significantly increasing by the day worldwide and is likely to increase by 174% by 2030. Primary revision is another major concern for total hip replacement with revision rates likely to increase by 137%. The first part of the article states the basic anatomy of the hip joint, different ligaments in the hip, the disorders associated with the joint, and evaluation of total hip arthroplasty. In the second part some of the major works are highlighted followed by a detailed discussion about different design considerations and wear-related issues in hip joints. More emphasis is given to the tribological behavior of implants under different conditions. The design aspects and several parameters which affect the wear rate in implants are summarized. Also, different testing methods which are used both in experimental and numerical techniques are reported to estimate the wear rates in hip implants with the evolution of hip implants since the early 20th century, in terms of different designs, materials and wear hip implant arthroplasty is known as one of the best advancements in healthcare. Further research is needed to establish to improve the life expectancy of hip implants.

The total hip prosthesis is considered one of the greatest advancements in orthopaedic surgery in the early 20th century. In hip implant replacement, the stem is inserted into the femur and femoral head, acetabular cup, and backing cup over the stem. This felicitates the normal range of motion and stability of an individual compared to the natural hip joint. Several different types of biomaterials are used in the total hip prosthesis. Where the combination of UHMWPE, CoCrMo alloy, and Ti-6Al-4 V alloy is widely used due to their superior mechanical properties over the others. In this work, these material combinations are used for the analysis with changes in the femoral head sizes from 24 mm to 48 mm to know the best size with the better material combination. Static structural analyses are carried out using Ansys R-19. Two sets of analyses are performed for two different material combinations between Ti-6Al-4 V, CoCr, and UHMWPE. The circular cross-shaped stem with change in femoral head sizes from 24 mm to 48 mm is used for analysis. The acetabular cup and backing cup thickness are kept constant throughout the study. The size of the acetabular cup and backing cup is considered 6 mm and 4 mm respectively. Loading and boundary conditions are considered as per the ASTM standards. Hip implant with Ti-6Al-4 V for stem and a 4 mm backing cup of CoCr and 6 mm acetabular cup of UHMWPE shown the least stress value of 203.48 MPa over all the other models which are used in the analysis. This work shows the analysis to know the effect of the change in femoral head size and also the change in material combinations used in hip implants. Further experimental work can be carried out to validate the results obtained in the current work.

Hip implants consist of a stem, femoral head, acetabular cup, and backing cup. There is a wide variety of sizes and lengths. Their adaptability is limited because of the inter-anatomical variations. There is no single fit-for-all implant design that satisfies the orthopedic requirement satisfactorily. In this work, the trapezoidal-shaped stem with three different cross-sections is considered. The femoral head size, acetabular cup thickness, backing cup thickness, and trunnion geometry were varied to arrive at the best possible combination. ANSYS R-19 was used to perform the static analysis. It is found that trapezoidal-shaped profile two has the least amount of stress and total deformation. The von Mises stresses were found to be higher when the femoral head size was between 32 mm to 40 mm in profile two. It was also observed that the femoral head with 24 mm has the least stress compared to higher head sizes. The maximum von Mises stress-induced in profile two was 141.0 MPa, the total deformation of 0.04436 mm and elastic strain of 7.6 × 10−4 mm/mm. Trunnion interface does not have a significant role with respect to the structural strength of the implant. From the findings of this study, it is inferred that profile two shaped stems with the femoral ball size of 36 mm, acetabular cup thickness of 2 mm and backing cup thickness of 1mm is best suited for the hip replacement. The major outcome of this study is the utilization of the DoE method to determine the optimized value of the implant.

Background: The Hip joint is the primary joint which gives stability to the human body. The wear and tear associated with age and other factors, require these joints to be replaced by implants using hip arthroplasty surgeries. Cobalt chromium alloy (CoCr), titanium alloy, stainless steel are some of the most common hip joint materials used for hip implants. The design requirement for hip joint implants are very stringent to avoid revision joint surgeries due to aseptic loosening. There are various choices in shapes and materials used for stem and acetabular designs. This makes it more difficult to make an informed decision on the type of design and material that can be used for hip implants. Methods: Circular, Oval, ellipse and trapezoidal designs with three individual cross sections (defined as profile 1, profile 2 and profile 3) are considered for the study. All models are modeled using CATIA V-6. Static structural analysis is performed using ANSYS R-19 to arrive at the best possible design and material combination for stem and acetabular cup. Results: It was found that, profile 2 of all the four designs has the lowest possible deformation and von Mises stress when compared to profile 1 and profile 3. In general, profile 2 with trapezoidal stem has best outcomes in terms of its mechanical properties. Besides, stem designed with material CoCr and its associated acetabular cup with CoC (ceramic on ceramic) material can produce an implant having better properties and longer durability. Conclusions: CoCr was found to be the preferred choice of material for stem design. It was also observed that, irrespective of material considered for the analysis profile 2 with trapezoidal stem showcased lesser deformation and von Mises stress over the other eleven models. For analysis involving acetabular cups, CoC implants exhibited better mechanical properties over the conventional CoPE (Ceramic on polyethylene) materials such as Ultra-high molecular weight polyethylene (UHMWPE). It is inferred from the findings of this study that, the profile 2 with trapezoidal stem design made of CoCr material and acetabular cup made of CoC material is best suited for hip joint implants.

Development of new materials in place of existing traditional metals and alloys to meet specific requirements is taking place worldwide. Natural fibre reinforced composites are being considered as one of the alternative materials which can find scope in indoor and low load bearing applications. The biodegradability and low density make them attractive, while inherent hydrophilic nature of the fibre is a challenge for the engineering applications. Surface modification to the fibres by chemical treatments makes them as an alternative reinforcement material in the field of composites. In the present work, Grewia Serrulata bast fibres were subjected to chemical treatments and stitched into unidirectional woven fabrics. Treated and untreated fibre reinforced laminates were fabricated by hand layup process. Sliding wear behaviour of the prepared specimens was studied as per ASTM G-99. Materials with relatively lower wear rate are preferred for the tribological applications. The study shows that acetylated Grewia Serrulata fibre reinforced and permanganate treated fibre reinforced polyester samples showed significant wear resistance compared to neat resin and untreated fibre reinforced specimens.