Pallavi D. Pawar

Bio: Pallavi D. Pawar is an academic researcher. The author has contributed to research in topics: Modal analysis & Nanotechnology. The author has an hindex of 1, co-authored 2 publications receiving 2 citations.

Assessment of Boundary Conditions for FEA of Mounting Bracket Using Co-relation with Experimental Results

Abstract: An engine mount is a structure that holds the engine to the chassis.The engine mounting plays significant role in reducing the noise and vibrations for improving vehicle ride amenity. The Automobile engine chassis system may experience unwanted vibrations caused by interference between the road and the engine. Engine bracket has been designed as a structure to support engine. Due to vibrations of engine the holes on the engine Bracket get expanded which leads to the failure of bracket. This paper presents experimental and Finite Element analysis of a typical engine mounting bracket. In this paper we have explored usage of Modal Analysis in FEA to determine the frequency band and check the bracket for safety. Hence in this paper, we have undertaken experimental analysis for co-relation to establish variation of percentage and thus determine the nature of Boundary conditions to be used in FEA for more accurate analysis. Experimental analysis is done by Fast Fourier Transform analyzer. Finite Element analysis includes Static and Modal analysis using ANSYS15.0 which will determine natural frequency of engine bracket.

An overview of antimicrobial nanoparticles for food preservation

Abstract: Nanotechnology opens up new possibilities for food innovation at an incredible rate, yet new technology needs evaluations of both potential negative impacts and numerous good effects. We aimed to cover some of the latest breakthroughs in nanotechnology and their application to food processing in this overview. Applications of nanoparticles in the food sector are growing rapidly. Nanoparticles (NPs) play a significant role in enhancing food quality by protection and preservation and are preferred over traditional preservatives. In this work on organic and inorganic nanoparticles in various forms such as single and multiple metal oxides, polymeric nanocomposite, nanocapsules, etc., as well as various methods of their preparations are discussed. Nanoparticles in food are currently most explored for their antimicrobial applications; factors affecting their antimicrobial potential, their antimicrobial mechanisms, and laboratory methods applied to evaluate antimicrobial potentials are also discussed. Various properties of NPs in relevance to antimicrobial activities and methods used for their characterization are also discussed. Antimicrobial NPs used for the purpose in various ways such as active packaging, mixed in food, incorporated in edible film and coating, etc. discussed. In the current state NPs used in the food industry, have various concerns such as safety, and regulatory policies relevant to preparing, processing, packaging, and consumption are discussed. NPs do possess some functional properties and harmful effects as well in this relevant future perspective of antimicrobial NPs in food and their other applications explored in current work. Various aspects of the most intensively studied NPs as an antimicrobial in food technology such as silver oxide, and zinc oxide, are discussed.

Probabilistic void detection using FEA

Abstract: Shaft is the important mechanical component used to transmit power and torque. Manufacturing of shafts by various manufacturing processes specially casting may induce imperfections like voids or porosity in the shaft. Detection of such imperfections becomes necessary in crucial components like shaft to avoid its adverse effects. The voids can vary in size and shape and could be present at various locations. The imperfections can be compensated in condition where shaft is not exposed to extremity. However voids can have adverse effect on shaft being exposed to operating conditions or environment of vibrations. This can also occur when a shaft is exposed to environment for longer duration of time. This condition also fosters the growth of voids. Ultimately the crack is formed being followed by void nucleation, void growth and void coalescence. If this condition continues the crack propagation accelerate resulting in failure of shaft. Therefore, it is necessary to address the problem of voids. The presence of void, size and location of void affects the natural frequency or total deformation of shaft. By using concept of natural frequency or total deformation presence of void can be detected. This can be done by comparing the natural frequency or total deformation of shaft without void with that having voids. The same study can be done to know the size and location of void for shaft geometries with different diameters. It has been found that the presence of voids gives a significant change on the natural frequency and the total deformation of the shaft.

Sonlu Elemanlar Hesaplama Parametrelerinin Sac Metal Şekillendirme Simülasyon Süresi ve Hassasiyetine Etkisinin Tespiti

Abstract: Bir sonlu elemanlar analizinin en onemli ciktisi tahmin hassasiyetidir. Tahmin hassasiyetine etki eden parametreler prosesten bagimsiz durumda olan ve modelleme adimlarini olusturan sonlu elemanlar hesaplama parametreleridir. Simulasyon hassasiyetinin yani sira ozellikle seri imalat endustrisi acisindan simulasyon cozum suresi bir diger kritik parametredir. Sonlu elemanlar analizlerinde verimin yukseltilebilmesi icin hassasiyetten odun vermeden minimum surede cozumun tamamlanmasi gerekmektedir. Bu kapsamda hesaplama parametrelerinin iyi analiz edilip hassasiyete ve simulasyon suresine etkilerinin tespit edilmesi onem arz etmektedir. Yapilan calismanin amaci, sonlu elemanlar hesaplama parametrelerinin sac metal sekillendirme simulasyon suresi ve hassasiyetine etkisinin tespit edilmesidir. Bu kapsamda non-lineer sac metal sekillendirme simulasyonlarinda hesaplama parametrelerinden simetri durumu, eleman boyutu, eleman formulasyonu, integrasyon nokta sayisi, zaman adim araligi, adaptiv ag yapisi derecesi, sekillendirme hizi etkisi, plastisite modeli ve cozumun gerceklestirildigi sistemin cekirdek sayisi olmak uzere genis bir kume analiz edilmistir. Sac metal sekillendirme prosesi olarak malzeme sekillendirilebilirlik ozelliklerinin belirgin sekilde analiz edilebildigi kare kutu cekme prosesi tercih edilmistir. Malzeme olarak ise gelismis yuksek mukavemetli celiklerden TRIP780 kullanilmistir. Sonlu elemanlar analizi hassasiyetinin belirlenmesi amaciyla sekillendirme kuvvetinin zimba ilerleme mesafesine gore degisimini temsil eden deneysel egri referans alinmistir. Sonrasinda belirlenen parametrelerin degisken degerlerinde simulasyonlar gerceklestirilmis olup her parametrenin hassasiyete ve cozum suresine etkisi tespit edilmistir. Bu kapsamda deneysel egrinin tahmin edilebilirligi her parametre icin incelenmistir. Yapilan simulasyon sonucunda sureye etki eden en baskin parametrenin sonlu elemanlar modelinin simetri durumu oldugu tespit edilmistir. Parametre kumelerinden sureyi minimize eden parametrelerin tespiti sonrasinda elde edilen en verimli simulasyon sonucunda baslangic durumuna gore hassasiyetten odun vermeden zamandan %90 oraninda tasarruf edilmistir. Baslangicta 2514 saniye suren simulasyon ayni hassasiyeti icerecek sekilde 94 saniyede tamamlanmistir.

Ultrashort laser sintering of metal nanoparticles: A review

Abstract: The unique shape and size dependant properties of nanoparticles (NPs) are responsible for their emerging, extensive applications in everyday industry. The application of NP inks for printed flexible electronics requires an additional post processing step since the presence of additives and stabilizers in the NP based inks often results in inferior electrical properties of the printed patterns. Laser sintering is a well-established technique for past number of years and is extensively used with continuous wave (CW), long, and short pulsed lasers. The literature is enriched with conventional sintering methods however the field of ultrashort laser sintering is relatively under-reported compared to CW laser and nanosecond laser-based techniques. This study concisely focuses on the potential use of ultrashort laser pulse processing of NPs and NP based thin films. The review provides the recent advances on ultrashort lasers sintering with a key focus on femtosecond laser pulses. • The review presents a study of nanoparticles (NPs), their deposition and post processing techniques with a key focus on ultrashort laser sintering. • NPs and NPs based thin films are discussed. • Role of ultrashort pulses in laser sintering, laser crystallization and laser annealing is discussed. • Potential to use two-temperature phenomenon in thin film laser processing.

Fatigue failure behaviour of horn mounting bracket using finite element analysis

Abstract: The aim of this present work is to find natural frequency for both existing and proposed horn mounting bracket designs to avoid the possibility of resonance. Next is to find out the dynamic behavior of existing bracket assembly from 5 to 17.3 Hz at the peak to peak distance of 10 mm by means of harmonic response analysis and then to find out the fatigue life using Goodman curve by vibrating the bracket assembly at first resonance frequency at 1.5 G acceleration. Finite element analysis (FEA) is carried to analysis the horn mounting bracket using ANSYS workbench software.

Analysis and evaluation of fatigue strength for engine bracketconsidering load characteristics

Abstract: In order to explore the load characteristics and fatigue characteristics of the engine bracket during the working process, the automobile engine bracket is taken as the research object and the force characteristics are analyzed. This paper provides a theoretical basis for the research and design of the engine support, thereby improving the reliability and durability of the engine bracket. Under cyclic loading, the fatigue characteristics are analyzed through the bench test. According to the experimental results, the dangerous points of the engine bracket are judged. According to the S-N curve cluster, the estimated range fatigue life of the engine bracket is 34236 times to 127219 times. When the load level is low, the life span changes significantly with the stress. As the load increases, when the stress level reaches a certain level, the fatigue life is less affected by the load. As the load increases, the fatigue life shows a slow decreasing trend. When the stress level is lower than the equivalent stress threshold value, the stress will not cause fatigue failure on the specimen, and the specimen has an infinite life. This paper lays a foundation for the prediction of fatigue life and the bench test of fatigue durability of the engine bracket subjected to complex and variable random loads. At the same time, the research method can also be used to estimate the fatigue life of other bearing parts.

Utilizing Imine Bonds to Create a Self-Gated Mesoporous Silica Material with Controlled Release and Antimicrobial Properties

Abstract: In recent years, silica nanomaterials have been widely studied as carriers in the field of antibacterial activity in food. Therefore, it is a promising but challenging proposition to construct responsive antibacterial materials with food safety and controllable release capabilities using silica nanomaterials. In this paper, a pH-responsive self-gated antibacterial material is reported, which uses mesoporous silica nanomaterials as a carrier and achieves self-gating of the antibacterial agent through pH-sensitive imine bonds. This is the first study in the field of food antibacterial materials to achieve self-gating through the chemical bond of the antibacterial material itself. The prepared antibacterial material can effectively sense changes in pH values caused by the growth of foodborne pathogens and choose whether to release antibacterial substances and at what rate. The development of this antibacterial material does not introduce other components, ensuring food safety. In addition, carrying mesoporous silica nanomaterials can also effectively enhance the inhibitory ability of the active substance.