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Residual stresses play a vital role in determining the quality of the turned components. Numerical modelling of residual stresses provides a deep insight of the process mechanism and increases the productivity by conserving time, material and manpower. In parallel turning process, two tools are engaged simultaneously to perform the turning process. In this research work, numerical investigation was done to determine the influence of chamfer width and chamfer angle for various cutting speeds and feeds on the surface residual stresses. The numerical analysis was carried out utilising a software program, ABAQUS 6.14. The work and tool material are AISI 4340 steel and carbide. CPE4RT four node plane strain element was used for the analysis. The chip was separated from work material based on Johnson-Cook damage criterion. Surface friction between cutting tool and chip is modelled by employing penalty contact approach. The coefficient of friction was taken as 0.3. With the increase in chamfer angle and chamfer width, the surface residual stresses increase. This is caused due to the increase in cutting temperature and plastic strain. Maximum circumferential and axial compressive residual stress of 415 MPa and 445 MPa is obtained for a chamfer width of 0.2 mm. The cutting speed was 150 m/min and feed 0.1 mm/rev. On the whole, the usage of chamfered cutting tools proved to be beneficial in imparting higher compressive residual stresses in parallel turning process.

Nose radius of a cutting tool is an important factor in finding the surface integrity of turned parts. The current research work deals with numerical analysis of surface residual stress generated during parallel turning using finite element method based software. Appropriate material model was used for parting the chip from work material. Nose radius is a vital process variable especially in parallel turning. The main motive of the current research work is to estimate the influence of nose radius on axial and circumferential residual stresses retained by machined work surfaces. The results revealed that with the increment in cutting tool nose radius, the residual stress of compressive nature along cutting and feed direction increases for the machined surface of front and rear tool. For all the nose radii, residual stresses raised with the rise in cutting speed. For nose radius of 0.5 mm and 250 m/min cutting speed with feed 0.2 mm/rev, the highest compressive circumferential and axial stress of the surface turned by second tool is 1696 MPa and 1838 MPa respectively. Higher nose radius causes larger dead metal and stagnation zone which in turn causes higher surface residual stresses.

Phase change materials (PCMs) have received substantial interest for their ability to store and release latent heat for energy conservation and thermal control purposes. PCMs are available in a variety of latent heat and melting points but their performance is low due to low value of thermal conductivity which limits its usage. The addition of highly thermal conductivity nanoparticles, porous metal foams and encapsulation methods have been used to address this issue and try to fix the low thermal conductivity of PCMs which is broadly discussed in this manuscript. The ability of PCM to store and release the thermal energy prompted the researchers to use it in potential applications. The energy retained and emitted by PCMs may be used for a variety of purposes, such as in photovoltaic (PV) panels, thermoelectric generators, building air-conditioning, air and water heating systems, heat exchangers, desalination solar stills, textiles, thermal management of electronic equipment and batteries and food packaging. Therefore, in this review, first the advancements in thermal properties of PCMs are thoroughly discussed in terms of enhancement in melting and solidification rates. After that, the use of PCMs in various applications is then explored, and conclusions are drawn accordingly. Based on analysis of recent literature, it was discovered that the phase transition temperature, phase transition enthalpy and thermal conductivity are three important parameters for the selection of an appropriate PCM for use in various applications. The current status of these advanced energy storage materials is also presented in this review. Lastly, some challenges and future recommendation are also proposed for future researchers which will bring a revolution in thermal management field.

Over the past decade, outcomes for patients with acute ST-segment-elevation myocardial infarction (STEMI) have been improving in the developed world - mainly, USA and Europe. This is as a result of an organized revolution in AMI (Acute Myocardial Infarction)-care in general and STEMI-care in

In the past decade, outcomes for patients with acute ST-segment-elevation myocardial infarction (STEMI) have improved in the developed world as a result of an organized revolution in STEMI-care. Concurrently, the Acute Myocardial Infarction (AMI) burden in the developing world is steadily rising.