Nov'19

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Nanofluids have the potential to minimize these thermal resistances and the industries that could benefit from such improved heat transfer fluids are very varied. In the paper, �An Experimental Investigation of Heat Transfer Enhancement Using Al2O3 Nanofluid in Circular Tube with Tight Spring Insert�, the authors, Parinam Anuradha, Harendra Kumar, Ramandeep and Sachin Raghav, have investigated and analyzed the thermal properties of nanofluid-composed of distilled water and Al2O3 nanoparticles at different particle volume fractions (0.5%, 1.0% and 1.5%) in a circular copper tube fitted with tight spring insert. The study suggested that Nusselt numbers continuously increased with the volume fraction and temperature of the nanofluids and Reynolds number, whereas the friction factor was found to be minimum at a volume fraction of 1.0%. The thermal viscosity of Al2O3 water-based nanofluid was minimum at 40 �C and 1% of volume concentration of nanoparticle.

Casting process is the most versatile manufacturing process. It involves pouring of metal into a mold, wherein the mold material and molding method must be selected with care. The Furan-No-Bake (FNB) sand molding is known to produce castings with high strength and good surface finish. Many tangible and intangible parameters could affect the soundness of sand casting, which in a way ends up in reducing the strength of castings and worst finish of the casting surface. It is a very tedious process to characterize the quality of FNB cast product due to the complex existence of parameters that affect the quality of the motor body casted product. The influence of the casting parameters such as resin percentage, catalyst percentage and temperature of sand at mixing on the compressive strength of the mold could indicate the robustness of the mold. In the next paper, �Sensitivity Analysis of Furan-No-Bake Sand Mold System Parameters�, the authors, Shailee G Acharya, Manojkumar V Sheladiya, Jaimin G Pandya and Ghanshyam D Acharya, have developed a model to evaluate the compressive strength based on the percentage of resin and catalyst and temperature, and performed sensitivity analysis to identify and compare the influence of the casting parameters. Based on the sensitivity analysis, their study indicated that compressive strength increases with the increasing resin percentage and/or with decreasing catalyst percentage and/or decreasing temperature of sand at mixing. The study concluded that compressive strength is more sensitive to temperature followed by resin percentage and catalyst percentage.

The constantly increasing costs and demand for energy have prompted theoretical and experimental researchers on the absorption of refrigeration systems and solar energy-based systems. Simplified cost minimization methods adopt the calculation of the economic costs of all the internal flows and products of the system by formulating thermoeconomic cost balances. Thermoeconomic Input�Output analysis provides general relationships between the product and the resource with the efficiency for each component of an energy system. In the paper, �Thermoeconomic Input-Output Analysis Applied to Ammonia-Water Absorption Systems, the authors, Sanjay Khatwani and Govind Maheshwari, have analyzed Fuel Product (FP) relationship using TAESS (Thermoeconomic Analysis of Energy Systems Software) to evaluate the effects of design variables on cost. The study suggests values of optimum design variables to make the system cost-effective.

Occupational noise is known to be hazardous for human beings. Very high noise level in forging shops is also considered to lower the labor productivity. However, occupational noise is being accepted as an integral part of the job. In every industry, need arises to assess the noise induced, and more so in forging industry where hearing loss among workers is known. In the paper, �Occupational Noise-Induced Auditory Fatigue Among Indian Forging Industry Workers�, the authors, Kamaljeet Bhambri, Ishbir Singh, Harwinder Singh and Tejeet Singh, have investigated the noise exposure levels and hearing loss among Indian forging workers. The sound pressure level measured was ranged between 90 db and 120 db, which was above the OSHA limit of 80 db as recommended for such type of industry. The audiometry results showed that permanent hearing loss is prevalent among 95% workers.

Heat exchangers with convective heat transfer of fluid inside the tubes are frequently used in the many engineering applications. Heat transfer enhancement technology has been developed and widely applied to heat exchanger applications. Optimizing the design and development of heat exchangers that are commonly used to transfer heat between two passing fluids at different temperatures without mixing of fluids is gaining importance day by day. Present day emphasis is on the lookout for some kinds of inserts which can be placed in the flow passage to augment the heat transfer rate thereby reducing the diameter of the flow passage. In the paper, �CFD Analysis of Heat Transfer Enhancement Using Spring Turbulator as Insert in Corrugated Pipe Heat Exchanger�, the authors, Parinam Anuradha, Gourav Gupta and Mohd. Ahmad, have studied the effect of inserts like corrugation on the inner pipe, helical spring insert on inner pipe and combination of both. The study suggested that by providing helical spring insert as an obstacle in the fluid path, the pressure drop increased significantly. The study suggested that at lower pumping powers, the heat transfer can be more effective with the use of corrugation alone as an insert.

S V Srirama Rao
Consulting Editor

Article   Price (₹)
An Experimental Investigation on Heat Transfer Enhancement Using Al2O3 Nanofluid in Circular Tube with Tight Spring Insert
100
Sensitivity Analysis of Furan-No-Bake Sand Mold System Parameters
100
Thermoeconomic Input-Output Analysis Applied to Ammonia-Water Absorption Systems
100
Occupational Noise-Induced Auditory Fatigue Among Indian Forging Industry Workers
100
CFD Analysis of Heat Transfer Enhancement Using Spring Turbulator as Insert in Corrugated Pipe Heat Exchanger
100
Contents : (Aug' 2019)

An Experimental Investigation on Heat Transfer Enhancement Using Al2O3 Nanofluid in Circular Tube with Tight Spring Insert
Parinam Anuradha, Harendra Kumar, Ramandeep and Sachin Raghav

The paper summarizes the thermodynamic performance of an irreversible singlestage The paper investigates the thermal properties of Al2O3 water-based nanofluid in a circular copper tube fitted with tight spring insert. The nanoparticles were dispersed in distilled water. Thermal conductivity, Nusselt number, force convection heat transfer coefficient, viscosity, pressure drop and friction factor at different particle volume fractions (0.5%, 1.0% and 1.5%) were analyzed. The heat transfer test section was fabricated to supply constant heat flux. The results showed that Nusselt number continuously increased with the volume fraction and temperature of the nanofluids. However, the friction factor was found to be minimum at a volume fraction of 1.0 vol.%. The Nusselt number of nanofluid was approximately 43.2% greater than that of the base fluid at a volume fraction of 1.0% vol.


© 2019 IUP. All Rights Reserved.

Article Price : Rs.100

Sensitivity Analysis of Furan-No-Bake Sand Mold System Parameters
Shailee G Acharya, Manojkumar V Sheladiya, Jaimin G Pandya and Ghanshyam D Acharya

Furan-No-Bake (FNB) sand mold system is a technology in high demand due to its good surface finish, dimensional stability and shakeout characteristics. It is a very tedious process to characterize the quality of FNB cast product due to the complex existence of parameters that affect the quality of the motor body casted product. In this paper, a mathematical model has been developed based on the experimental data, and sensitivity analysis was performed to identify and compare the influence of the casting parameters such as resin percentage, catalyst percentage and temperature of sand on the compressive strength of the mold and to know the parameters that must be carefully controlled.


© 2019 IUP. All Rights Reserved.

Article Price : Rs.100

Thermoeconomic Input-Output Analysis Applied to Ammonia-Water Absorption Systems
Sanjay Khatwani and Govind Maheshwari

The paper presents thermoeconomic input-output analysis of a single-stage vapor absorption system operating with ammonia-water mixture under steady state conditions. Thermoeconomic input-output analysis provides general relationships between the product and the resource with the efficiency of each component of an energy system. This model is a fundamental concept of symbolic thermoeconomics. In this paper, the authors have built a productive scheme from the physical structure of the Vapor Absorption Refrigeration Systems (VARS) that explains the resources distribution throughout the system. The definition of physical structure consists of a pair of components that connects each flow of the system. The complete productive structure of the whole absorption system analyzed is shown graphically. This approach allows one to obtain the Fuel-Product (FP) table, a mathematical representation of thermoeconomic input-output model. FP table plays a key role in the various approaches of thermoeconomics like cost formation process and thermoeconomic diagnosis. The complete analysis is performed using Thermoeconomic Analysis of Energy Systems Software (TAESS).


© 2019 IUP. All Rights Reserved.

Article Price : Rs.100

Occupational Noise-Induced Auditory Fatigue Among Indian Forging Industry Workers
Kamaljeet Bhambri, Ishbir Singh, Harwinder Singh and Tejeet Singh

Mechanization in India is primarily concentrated in the manufacturing sector, where health and safety of workers is given lowest priority. The small-scale industry is trailing behind in providing health and safety to workers, and more particularly to unprotected occupational noise and the resultant Noise-Induced Hearing Loss (NIHL). There is a need to assess the occupational health and safety levels at the shop floor of the forging industry. The paper assesses the occupational health and safety practices in forging industry. The sound pressure level was measured by vibration meter (SVAN 958A). The sound pressure level measured at ten sites in the shop floor ranged from 90 db to 120 db. The sound pressure level was found to be above the Occupational Safety and Health Administration (OSHA) limit (80 db as recommend for the industry). Audiometric test was conducted for different age groups of forging workers, and it was found out that about 95% suffered from NIHL.


© 2019 IUP. All Rights Reserved.

Article Price : Rs.100

CFD Analysis of Heat Transfer Enhancement Using Spring Turbulator as Insert in Corrugated Pipe Heat Exchanger
Parinam Anuradha, Gourav Gupta and Mohd. Ahmad

The paper employs Computational Fluid Dynamics (CFD) tools to analyze the augmentation in heat transfer in counterflow Double Pipe Heat Exchanger (DPHE) with arrangements and inserts like corrugation on the inner pipe, helical spring insert in inner pipe and combination of both. ANSYS FLUENT-15.0 was used in the investigation to predict the effects of the arrangements on overall heat transfer coefficient, heat gain, friction factor and pressure drop. Mass flow rate of water was taken such that the Reynolds number ranged from 10,000 to 15,000. The variation in the friction factor and Nusselt number was plotted and analyzed against the Reynolds number. The results showed that there was a considerable increase in heat transfer rate when an obstacle and/or modified surface (like corrugation) was inserted on the flow path; however, this increase was at the cost of pressure drop. 7% increase in Nusselt number was achieved by incorporating the corrugation on the pipe with only 23% increase in the friction factor, while this increase in Nusselt number was 4.5% and 8% in the case of tube with spring insert and combination of corrugation and spring both, respectively, accompanied by an increase of 374% and 386% in the friction, which cost a lot of pumping power.


© 2019 IUP. All Rights Reserved.

Article Price : Rs.100