In modern days, the vapour compression refrigeration system is followed in almost all air-conditioning applications. Due to the high ambient temperature during extreme summer conditions, the commercial vapour compression refrigeration system made with cost competitiveness are not in a position to meet the required indoor conditions (27°C Dry Bulb Temperature and 19°C Wet Bulb Temperature) within a

Cobalt-chromium alloy (F-90) and duplex stainless steel (DSS-2205) belong to the family of metallic biomaterials, which are frequently used for the manufacture of dental prosthetics, artificial implants including knee and hip joints. This article addresses the investigation highlights of electrical discharge machining (EDM) of Co-Cr alloy and duplex stainless steel using different electrode materials

Failure time prognosis in manufacturing process plays a crucial role in guaranteeing manufacturing safety and reducing maintenance loss. However, most current prognosis methods face great difficulty when handling massive data collected from manufacturing process. Convolutional neural network (CNN) provides an effective way to extract features with massive data. Due to the difference between images

Digital manufacturing is a necessity to establishing a roadmap for the future manufacturing systems projected for the fourth industrial revolution. Intelligent features such as behavior prediction, decision-making abilities, and failure detection can be integrated into machining systems with computational methods and intelligent algorithms. This review reports on techniques for Ti6Al4V machining process

Lungs expand during breathing through increasing the space in the chest cavity. The mechanical properties of the lung play a pivotal role for space, which provides during breathing. Smoking via chronic obstructive pulmonary disease (COPD) can affect this mechanical function through the alteration of the mechanical properties of the lung tissue. Recently our group performed an experimental study to

Design standards of preventing “plastic collapse” and “excessive overall plastic deformation” for pressure vessels are given in the ASME BPVC Section VIII Division 2 and EN 13445, respectively. These two aspects are both taken into account in the dual criterion, which could avoid the two failure modes at the same time. And the dual criterion has been adopted as Appendix B in the forthcoming revised

Thread tapping is one of the most important machining processes. Although thread tapping is a usual process and has been used for decades, the process still needs improvement for promising materials such as titanium alloys to increase the performance of the process. Titanium alloys are known as difficult-to-cut materials due to their low heat conductivity and elastic modulus. The aim of the work presented

Biodiesel, as an alternative fuel, has gained wide interest in recent years. However, despite the countless benefits, the enormous generation of glycerol-waste and higher production costs have been causing severe challenges to both the environment and the biodiesel economy’s survival. With the focus on maintaining its sustainability, the proper valorization of the crude glycerol is of vital importance

Sealing performance of standard rubber gaskets in the radial contact seal structure are observed through the experiment. A kind of profiled rubber gasket is proposed to replace the standard gasket. Leakage experiment and numerical simulation are carried out to study the sealing performance and failure mode of the profiled gasket. Several equations are presented to help analyze the failure reason. Results

An experimental investigation has been performed on the hot formability and densification characteristics of Al-Cu/Al two-layered structure composites. The two-layered composites having different Cu compositions in the Al-Cu layer such as (Cu: 5wt. %, 10wt. %, and 15wt. %) were prepared using the powder metallurgy (P/M) route. The composites were hot-pressed as layer by layer in a steel cylindrical

The aim of this paper is to demonstrate how the correct application of FEM analysis can be used to find effective solutions for the design of mechanical structures. The design of the inspection openings on the tanks is being considered. There are several existing tanks of the same dimensions (20 m high and diameter 10,2 m), but they have different wall thicknesses (9,6; 15; 20 and 25 mm). For inspection

In practical production, it is impossible even to measure the inter-lobe (meshing) clearance of a screw rotor pair. However, understanding of the clearance distribution is essential since it is a major leakage path which greatly affects the twin-screw pump performance. Previous publications did not disclose explicit detail on how to calculate the meshing clearance for screw rotor pairs with point-meshing

In this paper, the transformation of steam turbine regulating system from mechanical hydraulic regulation to electro-hydraulic regulation is realized. And the internal leakage mechanism of the hydraulic control switch valve and the electro-hydraulic proportional valve in the system is analyzed. With the use of hydraulic simulation software AMESim, the mathematical model of the electro-hydraulic control

The numerical investigation of steady two-dimensional free convection is conducted to analyze the thermal radiation and viscous dissipation effects on heat transfer characteristics in fluid saturated T-shape porous hollow enclosure. The nonlinear partial differential equations in terms of stream function, using Darcy’s law and Boussinesq approximation, are solved numerically using finite difference

This paper studied the effect of variable intake length manifold on filling and volumetric efficiency at starting engine speeds using numerical and experimental process. The investigation is based on acoustic supercharging phenomenon. For this purpose, 1-D engine gas-flow model was developed and optimum intake lengths for several low engine speeds were determined using acoustic theory based-resolution

Positive displacement motors are widely used underground power tools in oil and gas extraction. In order to solve the problems of the short life of the conventional positive displacement motor and the difficulty of machining the constant wall positive displacement motor, this paper proposes a metal bush stator. Based on theoretical analysis and tensile experiment of 304 stainless steel, a finite element

Fault diagnosis of various rotating equipment plays a significant role in industries as it guarantees safety, reliability and prevents breakdown and loss of any source of energy. Early identification is a fundamental aspect for diagnosing the faults which saves both time and costs and in fact it avoids perilous conditions. Investigations are being carried out for intelligent fault diagnosis using machine

A centrifugal pump operates under off-design operation conditions would lead to flow instability, additional energy loss or mechanical damage. Early detection is of great importance to its operation efficiency and safety. Sensorless monitoring technology based on motor current signature analysis (MCSA) is a cost-effective and non-intrusive technology to monitor motor-driven devices. However, existing

The present study accentuates the magnetohydrodynamic and suction/injection effects on the two-dimensional stagnation point flow and heat transfer of a non-Newtonian fluid over a shrinking sheet. The set of Navier-Stokes equations are converted into a system of highly non-linear ordinary differential equations by employing suitable similarity variables. The obtained self-similar equations are then

In the present study, galvanized High Strength Interstitial Free (HIF) steel sheets, and Dual Phase (DP780) steel sheets were used for the investigations. Resistance spot weld joints were fabricated between dissimilar steel sheets. The variation in dynamic resistance (DR) with the change in welding process parameters such as weld current, weld time and electrode force were used for establishing the

Titanium alloys are widely used in the aerospace industry due to their superior properties such as high strength and low density. As a new titanium alloy with higher strength and lower heat conductivity, titanium alloy TC21 is very difficult to cut and the cutting mechanism of this alloy needs to be investigated deeply. In the paper, to observe the cutting phenomenon in the turning process of TC21

The performance of an abrasive water jet machining (AWJM) process is mainly dependent on the jet diameter, which is prone to change with time due to the nozzle wear. The present study is aimed to monitor the nozzle wear during operation using vibrational spectrum. Experiments are conducted with four focusing nozzles of different diameters under same parameters considering water and water-abrasive mixture

A novel approach for modeling and simulation of cutting force and power consumption in relation to chip geometry has been proposed in end milling‌ of AISI D2 steel. It is carried out in two stages: experimental work and finite element method based numerical simulation. In the first stage, experiments are conducted on the AISI D2 steel at two levels of spindle rotational speed, axial depth of cuts and

A free convective flow of an incompressible and electrically conducting fluid through a vertical micro-channel of rectangular geometry was considered. Both plates were porous and heated alternately. A transverse magnetic field was applied across the channel. One channel wall surface was no slip and the other was super-hydrophobic. The purpose of the study is to examine the effects of super-hydrophobicity

The employment of hybrid material thin-walled sections in the vehicle body structure is an emerging approach adopted towards manufacturing of lightweight energy-absorbing components in the automotive industry. Utilizing multi-materials such as aluminum-steel in the automotive industry poses some manufacturing challenges in terms of joining technologies of dissimilar materials. Clinching is a cold forming

The usage of nano phase materials for strain sensing applications has attracted attention due to their unique electromechanical properties. The nanocomposite as piezo-resistive films provides an alternative for the realization of strain sensors with high sensitivity than the conventional sensors based on metal and semiconductor strain gauges. In this work, polymer based nano-composite with carbon nanotubes

This article investigates the hot corrosion behavior of P22/P91 dissimilar welds used in power plant applications. The hot corrosion behavior of P22/P91 dissimilar welds was observed under the exposure of molten salts Na2SO4 + 60% V2O5 (SM1) and Na2SO4 + 50% NaCl (SM2) at the temperature of 650°C and 750°C. The welds were fabricated by shielded metal arc welding (SMAW) process using the laboratory

Conventional twin-screw compressors are positive displacement machines that form working chambers between two helical, parallel rotors and an outer casing. This study investigates an alternative configuration of rotors for compressor applications, in which the working chambers are formed by continuous contact between meshing inner an outer rotors. This is a similar configuration to gerotor machines

In view of promoting the utilization of solar photo-voltaic energy for milk chilling application a custom designed milk chiller with DC compressors was fabricated. Two different DC compressors were used operating with HFC-134a and HC-600a refrigerants to ascertain the performance of HFC and HC refrigerants when used in solar powered application. In view of optimizing the performance of both refrigerants

Stainless steel 304 L tubes are commonly used in the fabrication of heat exchangers for nuclear power stations. The stress corrosion cracking (SCC) of 304 L tubes in hydraulically expanded tube-to-tubesheet joints is the main reason for the failure of heat exchangers. In this study, 304 L hydraulically expanded joint specimens were prepared and the residual stresses of a tube were evaluated with both

This paper examines the behaviour of a hybrid nanofluid flow towards a stagnation point on a stretching or shrinking surface with second-order slip and melting heat transfer effects. Copper (Cu) and alumina (Al2O3) are considered as the hybrid nanoparticles while water as the base fluid. The governing equations are reduced to the similarity equations using similarity transformations. The resulting

In the present study laminar forced convective flow of nanofluid through a converging minichannel is investigated numerically by employing two phase mixture model. The heat transfer enhancement and the corresponding pressure drop are analyzed for the following range of parameters: Reynolds number (700 ≤ Re ≤ 1650), particle volume concentration (0% ≤ ϕ ≤ 4%) and converging angle (θ = 0.029°, 0.043°

In the present study turbulent flow in a circular cross-sectioned 90° smooth-walled pipe bend has been investigated numerically. The geometry of the model consisted of three sections: a straight inlet pipe of length 52 diameters, a 90° bend with radius of curvature 1 diameter, and a straight downstream pipe of length 52 diameters. Reynolds numbers from 5,000 to 120,000 were considered. The numerical

Electrical discharge machining (EDM) is a thermo-electrical process that can be conveniently utilized for generating complex shaped profiles on hard-to-machine conductive materials using metallic tool electrodes. In this work, composite tools made of copper-tungsten-boron carbide (Cu-W-B4C) manufactured by powder metallurgy (PM) route are used during machining of titanium alloy (Ti6Al4V). The effect

Wire electrical discharge hybrid turning (WEDHT) is one of the unconventional machining process following thermo-electric material removal principle to machine cylindrical components at meso and micro scale with very high accuracy and precision. Thermal simulation and validation of Ti6Al4V alloy on temperature profile, crater formation, rate of material removal during WEDHT process was reported less

Pulsation of current is widely employed in Tungsten Inert Gas (TIG) welding of titanium alloys. In the current study, the influence of welding speed and welding currents (peak and background) on the properties pulsed TIG welded Ti-5Al-2.5Sn alloy were investigated. The weldment characteristics which were analyzed included weld zone size, microstructure, residual stresses, tensile and impact properties

In this work, simulation has been carried out for multipass Gas tungsten Arc Welding of SS316L and their effects were studied for thermal, and residual stresses and compared with experimental results. The sequentially coupled thermo-mechanical, transient thermal and static structural analysis was modelled using ANSYS with relevant Ansys Parametric Design Language coding. Infrared thermography camera

In the present work, E-glass/polyester composite laminates were manufactured in a customized resin transfer mould (RTM) with different layers of fiber at selected resin injection pressures. Experiments were performed employing full factorial design to study the influence of number of fiber layers and resin injection pressure on mechanical properties of the composites. Analysis of variance was implemented

Manufacturers across varied segments look for materials having appreciable machinability and surface integrities. Machinability of Mg alloys is a vital aspect during their acceptance for different applications. The chip shape generated in the cutting operation is a crucial attribute dominating the surface roughness, besides the dimension’s precision and the tool lifespan. The study discusses the chip-formation

To guarantee the strength and precision of the final welding assemblies, it is necessary to cut welding grooves before welding thick workpieces. General methods to cut welding grooves on plane workpieces need much manual assistance, and some even need manual operation purely. Therefore, this paper proposed a robot system for cutting Y-shaped welding grooves with full automation. Flame cutting technology

Augmentation of thermal performance in heat transfer system has become research hotspot nowadays. Numerous techniques are carried out to pick up the effective heat transport mechanism for designing high efficient thermal frameworks which has extensive practical uses in industrial process. In the current study, mixture model has been implemented for better describing the characteristics of nanoparticles

This paper is to explore the motion accuracy of a novel picking robot constructed by wire-driven continuum structure and liner screw platform. The continuum structure features the hollow configuration, by which the object could be transported along its internal space, such as fruits harvesting. For discussing the precision theoretically and driving the presented robot, the kinematic model and workspace

Bursting disc overpressure relief device services as the last safety barrier in preventing catastrophic overpressure of the pressure vessel. The design of ultra-high pressure bursting disc device is a tough engineering issue as it requires both strength and sealing reliability under ultra-high working pressure. In this paper, a novel ultra-high pressure bursting disc device is proposed as well as the

The spray coating technique is used in this study to spread a thin layer of nanoparticle on a large flat substrate. The proposed spray coating techniques has a great potential for large scale productions, as these techniques have no restrictions on the substrate size and low utilization of the process parameters. In this study, a simple airbrush spray coating technique is used to deposit the multiwall

In this paper, the effects of theoretical models of materials and dies on finite element (FE) predictions of a hot forging process are presented, to provide process design engineers and researchers with some useful insight into the theoretical approaches on which they rely. The material was assumed to be rigid-viscoplastic or rigid-thermoviscoplastic and the dies were assumed to be rigid or elastic

The manufacturing industries are among the focused industries of any country according to their contribution to nations’ economies. Therefore, the appropriate utilization of all manufacturing/processing equipment is a high priority. The problem is the complexity to keep all the activities, operations, and use of equipment in synchronization with the reduction of all possible losses and defects. Such

This article deals with the photothermal conversion performance of solar glycol – multiwall carbon nanotubes based nanofluids were studied with various weight concentrations and time. A broad investigation was performed with various nanofluid samples with the help of a sun simulator. The measurement was conducted with solar glycol-MWCNTs based nanofluids with 0.1%, 0.2%, and 0.3% volume concentration

The present study aims at investigating the effect of submerged arc welding fluxes for enhanced corrosion resistance of structural steel welds. By varying the basicity index of submerged arc welding fluxes the corrosion resistance and mechanical properties of weld metal such as tensile strength, impact strength, microhardness in submerged arc weldments were evaluated. The result shows that with the

This article investigates the steady-state performance of a closed-circuit hydrostatic (HST) drive using a variable displacement pump and a variable displacement motor where the speed of the drive is varied by controlling pump or motor. The drive is operated over a wide range of load torque and speed in two modes of operation: the pump controlled mode and the motor controlled mode. The efficiencies

Development in the field of materials brings numerous newer grades, but the machinability studies over those materials have to be done. Drilling is the major manufacturing process which covers around 25% of machining processes. Magnesium AZ31 is considered for the present investigation to perform the drilling operation. Control over the responses like circularity, perpendicularity and cylindricity

The flat cross wedge rolling is an advanced forming process, which is used to produce thread shafts. In this work, a finite element model of flat cross wedge rolling thread shafts was established by the DEFORM-3D, and the effect of the forming angle, spreading angle, helix angle and flank angle on forming quality are investigated. The research results show that the forming angle, spreading angle, helix

Major studies related to the generation and control of wettability in engineering surfaces are focused on coatings and patterning of surfaces. However, investigations on anisotropic wetting induced by roughness texture after traditional surface generation methodologies such as CNC milling may be useful to optimize the selection of machining conditions such as feed rate of cutting tool. A comprehensive

Aiming at the influencing factors of spot welding quality and the shortcomings of the method of judging the spot welding quality based on the monitoring waveform curves: it is impossible to deeply analyze the differences between the corresponding monitoring waveform curves and spot welding qualities. In this study, according to the monitoring waveform curves of the welding current, inter-electrode

Research about the enhancement of the airlift pump performance by changing the geometry and operational parameters has drawn considerable attention in recent years. This paper presents a comprehensive review of some published research articles on the enhancement performance of the airlift pump and the future direction of the research. In the introductory section, the description, the application, and

This work proposes a novel observer based direct adaptive fuzzy second-order-like sliding mode control (SMC) method for a certain class of high order unknown nonlinear dynamical systems with unmeasurable states. An observer is firstly developed to estimate the tracking error vector directly, and the stability of the observer is analyzed based on Meyer-Kalman-Yakubovich (MKY) lemma. Based on the observer

This paper reports an investigation on the phenomenon of refrigerant outgassing in the screw pump of a hermetic reciprocating compressor oil supply system. The interfacial mass transfer between the refrigerant and the lubricating oil is modelled by means of a cavitation model based on the Rayleigh-Plesset equation, for cases of fixed and variable mass fractions of refrigerant dissolved in the lubricant

Nanometric surface roughness (NSR) is commonly produced in ultra-precision grinding (UPG). However, the NSR would be significantly affected by the sampling frequency (SF), i.e. sampling effect, since it is governed by rich low, middle, and high spatial frequency features. Hereby, the case study focused on discussing sampling effect in the NSR of UPG. The theoretical and experimental results have been

For a dual-motor-driven elliptical vibrating screen, the driving frequencies of the two motors are studied in this paper and it exposes the significant influences of different driving frequencies on the vibration direction angle of the self-synchronous system. A dynamic model is established to demonstrate the new concepts and innovative ideas put forth in this paper. Simulink and prototype experiments

The current study unveils the variation of surface integrity aspects (micro-hardness, surface crack density, and surface characteristics) for Ni55.95Ti44.05 shape memory alloy (SMA) with wire electric discharge machining (WEDM) process parameters, namely, pulse off time, wire tension, spark gap voltage, wire feed rate and pulse on time. The experimental results reveal that micro-hardness displays direct

The refrigerant R513A receives significant attention as an alternative to R134a used in water chiller, due to its lower global warming potential. However, whether R513A can directly and efficiently take the place of R134a in the twin screw compressor has not been verified. In this paper, a thermodynamic model is applied to compare the performance of R513A and R134a in a twin screw compressor. The leakage