Indian Journal of Production and Thermal Engineering (IJPTE)
The Indian Journal of Production and Thermal Engineering (IJPTE) has ISSN 2582-8029 (online), open-access, peer-reviewed, periodical bi-monthly international journal, which is published by Lattice Science Publication (LSP) in February, April, June, August, October and December. Authors can electronically submit articles throughout the year using the Article Submission System. Authors can format their article either in (i) a single-column format or (ii) as per the journal template. The submitted articles should not have been previously published or are currently under consideration for publication elsewhere. The journal does not accept brief or short notes for publication. The editors retain the right to reject any articles that lack quality or originality without sending them for review. All articles must fall within the journal’s scope and will undergo a double-anonymized peer-review process. Authors must confirm that they have read and understood the content of their submitted article and ensure that it meets acceptable English grammar and usage standards. To help with the proofreading process, authors can use tools like Grammarly or similar applications. As an open-access journal, authors must pay an Article Processing Charge (APC) to publish their articles and retain copyright. Additionally, authors should familiarise themselves with the editorial and publishing policies of the journal.
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Experimental Study and Numerical Simulation of Green Tea Drying Kinetics using a Heat Pump System Integrated with Auxiliary Electric Heating
Controlling the moisture removal process in Thai Nguyen green tea drying is a significant challenge due to the complex capillary-porous structure of the leaves and the high thermal sensitivity of bioactive compounds. This study proposes an advanced hybrid drying solution that combines heat pump technology (HPD) with auxiliary electric heating to optimise drying kinetics and energy efficiency. In addition to the experimental investigation of three multi-stage temperature-control modes, a mathematical model based on 1D moisture-diffusion partial differential equations (PDEs) was developed. This model was solved using the implicit finite difference method (FDM) in MATLAB to accurately describe the moisture concentration gradient from the core to the material surface in real time. The experimental and simulation results show high compatibility (RMSE < 0.05). The data indicate that the stepped drying mode (35–40–45°C) is the optimal strategy, reducing the drying time by 27.2% compared to the conventional constant-temperature heat pump method. This strategy ensures uniform moisture distribution and effectively prevents surface "case hardening." Among the six thin-layer kinetic models evaluated, the Midilli & Kucuk model exhibited superior performance, with a coefficient of determination (R2) of 0.9981 and an RMSE of 0.00179. The novelty of this research lies in establishing a "thermal safety zone" through a multi-stage heating mechanism, which maintains a maximum drying rate of 0.035 g/min during the critical falling-rate period. The findings confirm that PDE-based numerical simulation is a fundamental tool for optimising hybrid drying systems, enabling accurate prediction of the drying endpoint and establishing temperature profiles to preserve sensitive bioactive substances in industrial applications.
Copyright (c) 2026 Ngo Quang Truong, Nguyen Thi Viet Linh, Pham The Vu, Pham Van Duy (Author) https://creativecommons.org/licenses/by-nc-nd/4.0
Effect of Channel Width on Flow Characteristics in PEM Fuel Cell Anode and Cathode Flow Fields – a CFD Study
The performance of Proton Exchange Membrane Fuel Cells (PEMFCs) is highly influenced by the geometric design of the flow field channels that deliver reactants and remove byproducts. In this study, the effect of channel width in anode and cathode flow fields with a four-channel multiple-pass short serpentine (FCMPSS) configuration was investigated using Computational Fluid Dynamics (CFD) simulations in ANSYS Fluent under laminar flow conditions to identify optimal width combinations. The analysis includes three anode and cathode width combinations for a fixed channel depth of 1.25 mm and cell active area of 112 cm2 . The tested combinations are 0.8 mm, 1 mm, and 1.2 mm for the anode, and 0.6 mm, 0.8 mm, and 1 mm for the cathode, respectively. Flow rates are derived for the target current density of 0.7 A/cm2 . This study focuses on flow characteristics by excluding electrochemical reactions to understand the flow behaviour before incorporating electrochemical models, and was validated through a grid independence study and Reynolds number analysis. Simulation results showed that narrower channels significantly increase pressure drop and reactant velocity, thereby enhancing reactant convection and water removal. However, they can also increase reactant pumping power and the risk of membrane dehydration. Conversely, wider channels reduce pressure drop and velocity, thereby lowering pumping energy losses, but risk poor reactant distribution and local flooding. The configuration with 1.0 mm anode and 0.8 mm cathode widths achieved the most balanced performance, exhibiting moderate pressure drops of approximately 2044 Pa and 8822 Pa, and corresponding velocities of 4.76 m/s and 4.17 m/s, which support efficient transport phenomena while minimising energy losses.
Copyright (c) 2025 Dr. J. Karthikeyan, Dr. Ragul Kumar Kittusamy (Author) https://creativecommons.org/licenses/by-nc-nd/4.0
Experimental Study and Energy Evaluation of Heat Pump–Solar Hybrid Drying of Bitter Melon
This study experimentally investigates the performance of a hybrid drying system that integrates a heat pump with solar thermal energy, aiming to improve energy efficiency in the drying of bitter melon (Momordica charantia). The research focuses on the effects of slice thickness on drying time, Specific Energy Consumption (SEC), and the quality of the dried product. Drying trials were conducted using slices of bitter melon of three different thicknesses: 1 mm, 2 mm, and 3 mm. The hybrid system employed a flat-plate solar collector to preheat the inlet air before it entered the heat pump drying chamber. Results show that slice thickness had a significant effect on drying kinetics. Slices with 1 mm thickness reached the target moisture content in 4 hours, whereas 3 mm slices required up to 5.5 hours. The integration of solar preheating reduced total electrical energy consumption from 4.3 kWh to 2.7 kWh per batch, yielding an energy savings of approximately 37.2%. The SEC was also reduced, from 5.73 to 3.60 kWh/kg of evaporated water. In addition to energy improvements, the hybrid system helped retain favourable product characteristics, including a final moisture content of 10–12%, natural green colour, aroma, and essential bioactive compounds such as momordicin and flavonoids. These outcomes demonstrate the hybrid system’s potential as a sustainable solution for smallto medium-scale agricultural drying. A slice thickness of 1–2 mm is recommended for optimizing both drying efficiency and product quality. The findings support further research on the drying parameters that affect nutrient retention and the physical properties of dried agricultural products.
Copyright (c) 2025 Nguyen Thi Viet Linh, Dr. Pham The Vu, Nguyen Ngoc Quy (Author) https://creativecommons.org/licenses/by-nc-nd/4.0
Research on the Effect of Air Speed on the Condensation Process on the Air-Water Separator
Atmospheric water recovery (AWH) is a promising solution to overcome the shortage of clean water in arid regions, especially highland and desertified areas. There are many solutions to recover water from the atmosphere, such as absorption, adsorption, and various condensation-based technologies (condense and recover water), such as fog nets. These nets will retain water droplets when fog passes through, and using good hygroscopic materials, they will then recover water in the moisture-retaining materials. The solution of direct condensation of water vapour by creating cold surfaces with low temperatures also emerges as a promising option for energy savings. This paper presents the calculation process for selecting suitable equipment to build a model of an air-water separator with a compressor power of 1 HP. The study focuses on the influence of air velocity on the water condensation process on the surface of an evaporator with a vertical, smooth-tube condensing surface. The system's test results were obtained under different operating modes, including the surface temperature of the evaporator changing in response to the speed of change in air humidity conditions, which were approximately 45% in Hanoi, Vietnam. The experiment demonstrates that the system can operate effectively and separate water efficiently in a relative humidity condition of roughly 45%, which is a limitation of other systems. The results of this study also serve as the basis for future research into building larger-scale systems.
Copyright (c) 2025 Nguyen Xuan Binh (Author) https://creativecommons.org/licenses/by-nc-nd/4.0
An Investigation into The Enhancement of Heat Transfer in Roughened Ducts of Solar Air Heaters
One of the most crucial tools for the process of transforming solar energy into thermal energy is a solar air heater. Thanks to its low cost and ease of installation, solar air heaters have quickly become one of the most popular and widely used methods of harvesting solar energy. Low convective heat transfer coefficient values between the absorber plate and the air significantly reduce the solar air heater’s thermal efficiency. This is because absorber plates are used in solar air heaters. As a consequence, the absorber plate heats up, releasing a great deal of thermal energy into the surrounding space. This article presents the findings of a study that used computational fluid dynamics to investigate how heat is transferred in a solar air heater. The work for this project was done by the author (CFD). Researchers are now investigating the impact of the Re on the Nu. Commercial software known as ANSYS FLUENT 20 may be used to analyse and visualise the flow that happens across the duct of a solar air heater. This programme falls under the category of finite volume software. Using the programme helps get the job done.
Copyright (c) 2024 Gyaneshwar, Shikha Bhatt (Author) https://creativecommons.org/licenses/by-nc-nd/4.0
Component Level Failure Analysis of Mounting Strap Joint Fitted on Vehicle Engine Exhaust After-Treatment System
Exhaust Gas Processors (EGP) or Exhaust After Treatment Systems (EATS) are usually mounted on vehicle chassis or engine body with the help of mounting straps due to its ease of installation. It is prescribed for any industry to manufacture an optimized design of strap joint and duly test it before making an entry to the market. There is no standard method available to be followed by the industry for strap validation at an earlier stage. Most of the strap joint designed and tested based either on MAST test (done in the later stages) or on the experience. So, to test the strap joint at an earlier stage there is a need to design a component level strap joint validation method with a goal to assess the durability of strap joint vulnerable to fatigue failures due to vibration over-amplification in a bracketed after-treatment assembly while able of detecting any design flaws and eliminating or reducing numbers of potential test induced failures. The objective of this work is to define and document a systematic approach for component level strap joint validation method used to mount after treatment system components. Due to geometrical complexity and nature of material, geometrical nonlinearity and material nonlinearity were considered in the analysis. Also, for getting the most realistic results contact nonlinearity was also considered. And finally, out of various approaches investigated, an approach which was able to replicate failures in a more exact manner comparable to assembly level test was recommended as the component level strap validation method.
Exhaust Gas Processors (EGP) or Exhaust After Treatment Systems (EATS)
Copyright (c) 2024 Amulya Gupta, Kishor P Deshmukh, Chandraprakash S Sarpate, Kiran A. Kadam, Sunil Kumar Gupta (Author) https://creativecommons.org/licenses/by-nc-nd/4.0
Airflow Simulation in a Turbofan Engine: A Study of Flow Behavior
The efficient functioning of modern turbofan engines relies heavily on a deep understanding of airflow dynamics within critical components. This research paper presents a comprehensive investigation into airflow simulation within a turbofan engine, employing advanced computational techniques. The study focuses on flow behavior and makes use of SolidWorks for 3D modeling and ANSYS for simulation. The investigation centers on analyzing key flow parameters such as velocity, pressure, and temperature. The methodology involves creating an accurate 3D model of the turbofan engine excluding the compressor, combustion chamber, and turbine using SolidWorks to capture fine geometry and details. Subsequently, ANSYS is utilized to simulate the airflow within the turbofan engine, simulating realistic conditions and enabling the detailed analysis of flow behavior. The results of this study advance knowledge of turbofan engine technology and lay the groundwork for additional study and advancement in the area of aviation propulsion systems. In response to the evolving requirements of the aviation sector, the knowledge acquired from this research will serve as a priceless asset in the development of engines that are characterized by enhanced dependability, a reduced ecological footprint, and heightened fuel efficiency.
Copyright (c) 2023 Aminullah Bakhtyar, Ahmad Farzad Faqiri, Noman Tasal, MahboobullahMutahar, Suhrab Sheybani (Author) https://creativecommons.org/licenses/by-nc-nd/4.0
Design, CFD Simulation, Prototype, and Experimental Investigation of Indirect Active Solar Dryer for Banana
Indirect active tray solar dryer was designed, CFD simulated, and constructed for the drying of banana in Addis Ababa, Ethiopia. The experimental investigation was done after the CFD ANSYS Fluent simulation of different parameters based on the uniformity temperature and air flow distributions on the symmetry plane. The performance of the designed solar dryer was compared with that of the open sun dryer method, based on drying rate, moisture ratio, and moisture content on a wet and dry basis. From fourteen different mathematical drying thin layer kinetics models, the maximum correlation coefficient of 0.999574, the minimum root mean square of 0.0001352, and the minimum reduced chi-square of 0.007353 were obtained for the Verma et al. model for the slice banana in the designed active solar dryer. Recycling the air from the outlet of the drying chamber on the first day is not possible because the quality of the air is lower when compared with ambient air. The outlet air temperature and relative humidity of the drying chamber were 4.39℃ higher and 8.24% lower than the ambient air temperature and relative humidity respectively, so it is possible to recycle the air after the first day. The average moisture content removed from the product in the designed solar dryer and open sun dryer was 68.01% and 51.01%, respectively, in the 22 and half5 drying hour. The difference between the maximum and minimum moisture removal was 4.47%. It indicates there is a uniform drying in the designed solar dryer. The overall solar air collector efficiency was 33.80%and the maximum drying efficiency was 31.10 %.
Copyright (c) 2023 Tigabu Mekonnen Belay, Samson Mekbib Atnaw (Author) https://creativecommons.org/licenses/by-nc-nd/4.0
Production and Characterization of Pellets from Agricultural Residue: Cotton, Tur, and Soybean
Substituting biomass for conventional sources of fuel can help to provide cleaner energy. Woody biomass pellets are gaining popularity in the primary energy industry. Agricultural biomass is either burned on the farm or used as fodder for animals recently, which releases toxic chemicals in environment. Locally cultivated crop waste has potential to be more environmentally benign than imported biomass. As a result, residues of locally grown Cotton, Tur, and Soybean crops were used for pelleting in this study. The collected residues were sundried and shredded to particle sizes ranging between 2.36 mm to 4.75mm. The pellets were prepared without binder by using pelleting machine. The proximate and ultimate analysis of crop residue and pellet samples was carried out to check characteristics and applicability of pellets as bioenergy source. The thermogravimetric analysis was conducted to check thermal behaviour and SEM-EDS analysis was carried out to detect the inorganics present in ash sample. The obtained calorific values of cotton, tur, and soybean pellets are 3696.57, 3487.83, and 3281.65 Kcal/Kg respectively and moisture content is below 10% for all three types of pellets. The findings showed that crop residue pellets as an alternative to conventional fuel sources provide superior economic and environmental outcomes.
Copyright (c) 2023 Sayali Udakwar, Prof. Dilip Sarode (Author) https://creativecommons.org/licenses/by-nc-nd/4.0
Implementation of Permanent Magnet Propelling Phenomenon in Traditional Vertical Axis Wind Turbine System to Enhance the Performance and Efficiency
It is generally acknowledged that the energy as we now use, will not be adequate to meet the needs of all people on the planet in future, hence cleaner and more plentiful alternative energy sources are required which may be in the form of hybrid energy also. Renewable energy sources will certainly become more prominent. Modern civilizations need cheap, plentiful energy to survive, therefore, it is crucial for human civilization to create a sustainable, affordable, and environmentally benign alternative sources of energy. The global energy dilemma may have an efficient solution in the form of wind power. In current state of affairs, the air could seem like insignificant to any or all. However, we tend to all grasp that, the planet has shaped up with associate uneven surface, which suggest that the sunrays could strike these surfaces with variable intensities at numerous spot on its uneven surface. This creates associated degree of unequal degree of heating of the earth surface, that which causes variation in part of atmospheric pressure thereon. Then it leads to wind. The Kinetic energy of these air molecules is nothing but wind energy. A mechanical mechanism known as a wind turbine which transforms, kinetic energy which is there in the air around it into the required form of mechanical energy. Here in this research, we focused on the repellent qualities of permanently magnetized objects with similar poles. These innate qualities of magnetic propulsion are used here as an energy sources. Due to the inclusion of this components like magnetic repulsion, our VAWT system will operate more effectively even at lower wind speeds circumstance also. This magnet will produce a repulsive force that will add various sorts of kinetic energies to the wind turbines as they convert wind energy’s kinetic energy of into the necessary mechanical power when it’s employed as an extra source of energy in a VAWT.
Wind Energy and Renewable Energy Sources
Copyright (c) 2023 Sandesh Hegde, Dr. Ramachandra C G, Dr. Nagesh S N, Dr. Prashanth Pai M (Author) https://creativecommons.org/licenses/by-nc-nd/4.0
Development and Calibration of Automated Multiple-Ring Infiltrometer
An automatic triple-ring infiltrometer was developed using a set of pre-set sensors and transducer (AP 403, AP 404, AP 405 and AP 406, RAP001 and RAP002). The aluminum probe sensors were graduated and arranged in series to monitor the rate at which water is infiltrating into the soil layer. The working principle of automatic triple-ring infiltrometer was developed using six probes with depth calibration of 1.0mm, 26.7 mm, 12.4 mm, and 12.7 mm, respectively. The result obtained showed strong agreement with a coefficient of determination R2= 0.963, indicating positive proportionality between cumulative infiltration and time taken for the water to infiltrate at different depths. The instrument has a measuring accuracy of ± 0.3mm infiltration depth. The device works effectively under biochar amended soil and other soil formations with high precision. Accurate infiltration data generated by the instrument would be applied to estimate the depth of water available to plant and predict possible agricultural drought.
Copyright (c) 2023 Olotu Y., Parker-Ikharo, Rodiya A.A., Evboifo N.O, Jibril A.A., Diamond B. (Author) https://creativecommons.org/licenses/by-nc-nd/4.0
Sensitivity of PR2 Capacitance Soil Moisture Meter for Irrigation Scheduling
Accurate soil moisture content measurement is essential for designing a robust irrigation scheduling and integrated water resources management (I.W.R.M.). Capacitance-based sensors have widely been used to monitor soil moisture at different measuring depths coupled with continuous and instantaneous outputs. This study’s objective was to evaluate the PR2 capacitance moisture meter’s performance on mineral and organic soil water content. The outputs of PR2 in m3/m3 and vol.% were compared with gravimetrically measured soil moisture. The R.M.S.E. measurement at Site A at the first and second replicates increased from 0.49% to 0.67%. In contrast, the r2 value of 0.99 was obtained for the two replications when comparing the soil moisture content observed from gravimetric measurement and the automated outputs from the PR2 Probe soil monitor. The R.M.S.E. values were 0.48%, and 1.32% were estimated for the first and second replications at Site B. The result indicates that the PR2 Profile Probe could be a reliable alternative to other time-consuming, complex computer algorithms for accurate point measurement of soil moisture.
Copyright (c) 2023 Olotu Y., Omoakhalen A.I., Ososomi A.S., Gbalaja Mayowa, Alhassan A.I, Ayilaran C.I. (Author) https://creativecommons.org/licenses/by-nc-nd/4.0
Role of Power Electronics Devices in Grid Integration with Renewable Energy Source (Wind) and Challenges
We know that to growing population in India this time to use the renewable source to generate the electricity and most of the government and private companies do this very confident way. We know that the main renewable energy sources in our word is sun and wind with the help of sun and wind most of the company are situated the plant at that places where the efficiency and generation of electricity is more and more accuracy and fulfill the requirement of the electricity demand. Where this is depending upon the mostly to the renewable energy there to connect this farm to the grid system the power electronics devices play a very important role. We can say that yes wind energy and solar energy is the future management which is fulfill the requirement of the electricity generation demand. In this paper we discuss the different type of power electronics devices which is used in wind power generation system. In this paper we also discuss about some type of challenged which is coming when these farms connected to the grid.
Copyright (c) 2023 Apar chitransh, Dr. Surbhi gupta (Author) https://creativecommons.org/licenses/by-nc-nd/4.0
Tribology and Maintenance of Machinery – A Review
The present paper considers the tribological principles on the maintenance of machinery whose three important areas are – Preventive, Condition Based and Proactive. Although breakdown is kept out of view, the morphology and analysis of failure provide important inputs for maintenance strategies. Condition based maintenance depends on three D’s – Detection, Diagnosis and Decision. In many machinery systems, the problem of predicting the remaining useful life – the Proactive part of the program, and evaluating the cost benefits are of enormous importance. Here the authors endeavor to highlight how the tribologist can significantly improve the maintenance practice.
Copyright (c) 2023 Chandan Chattoraj (Author) https://creativecommons.org/licenses/by-nc-nd/4.0
Evaluation of Vibration Amplitude Stepping and Welding Performance of 20 kHz and 40 kHz Ultrasonic Power of Metal Welding
Today ultrasonic power technique is consider a mandatory technique which is always entered in many processes such as in metal and plastic welding to overcomes many issues, with aided of applying force (pressure) and supplied high frequency vibration, a solid-state weld can be generated by ultrasonic metal welding technique. That give a technique the ability to join not only a small components, whereas also to join thicker specimens, depend on a proper control of matching welding conditions. Therefore a welding performance can be study and compared after designed welding horn to resonance at frequencies of 20 kHz and 40 kHz. The analyses of the designed horn are completed through use a vibration mathematical expressions, modal and harmonic analyses to ensure the weldability due to applying ultrasonic power to the working area and also to compare the performance of joint at using two resonance frequencies of 20 kHz and 40 kHz. The dimensions of the horns were determined to match the selected resonance frequencies, which the lengths were calculated as 132 mm and 66 mm respectively. The analysis of the exciting modal indicates that the axial vibration modes of 19,584Hz and 39,794Hz are obtained in 10th mode, while the two frequency values are recorded 19,600 Hz and 39,800 Hz from the frequency response of the two horns. The weld strength between Al and Cu specimens with a thickness 0.5 mm were evaluated using tensile test, which the analyses were obtained under using different welding pressure and varied amplitudes. The results were recorded within exciting a horn with two different resonance frequencies, show the enhancement of weld strength and quality through control of stepping amplitude, the enhancement means obtain good strength of the weld, reduce sticking horn to specimen, and lower specimen marking
Copyright (c) 2023 Dr. Ziad Shakeeb Al Sarraf, Dr. Ahmed Fattah Ahmed, Mr. Khalid Alias Hammo (Author) https://creativecommons.org/licenses/by-nc-nd/4.0
Assessment of Urban Domestic Water Demand and Supply in Edo North, Nigeria
An exponential increase in the global population has seriously put pressure on land and water resources. It is projected that 33% of the worldwide people will be highly water-stressed by the 2050s if effective strategies are not developed. The study assessed urban domestic water demand and supply in Edo North senatorial district in Edo State, Nigeria. This is with the view of exploring some critical water resource variables to determine water security, distribution, and accessibility of safe drinking water in Edo North in Edo State in Nigeria. Integrated Water Resource Management Tools (IWRT) such as Water Poverty Index (WPI) and Water Accessibility Indicator (WAI) was applied. The results show that Auchi is highly water-stressed at the Estako-west area with MPI and WAI values of 0.24 and 0.33. Conversely, Okpella and Agenebode in Eskako central have MPI and WAI values 0.34 and 0.31, and 0.31 and 0.32. Sabo Gida Ora and Isobe in Owan East and West have better safe drinking water coverage and accessibility with the indicator values of 0.54, 0.53 [WPI], and 0.61 and 0.59 [WAI]. It is generally observed that the supply of potable water in the Edo North is highly unsecured and unsustainable to meet the current and future demand. Valuable and economic time is wasted to gather water from an average closest distance of 1.3 km from home to some designated water taps. In conclusion, it is imperative to design a robust integrated water policy that should include Private-Public-Partnership (PPP) to invest in the provision of safe drinking water.
Copyright (c) 2023 Bada, O.A., Alhassan A.I, Momoh E.O., Olotu Y., Osagioduwa, Dirisu H.I, Ayilaran C.I. (Author) https://creativecommons.org/licenses/by-nc-nd/4.0
Cop Enhancement of Vapour Compression Refrigeration System
This experimental investigation exemplifies the design and testing of diffuser at compressor inlet and nozzle at condenser outlet in vapour compression refrigeration system with the help of R134a refrigerant. The diffuser with divergence angle of 12°,14° and the nozzle with convergent angle 12°,14° are designed for same inlet and outlet diameters. Initially diffusers are tested at compressor inlet diffuser is used with inlet diameter equal to exit tube diameter of evaporator and outlet tube diameter is equal to suction tube diameter of the compressor. Diffuser helps to increases the pressure of the refrigerant before entering the compressor it will be helps to reduces the compression work and achieve higher performance of the vapour compression refrigeration system. Then nozzles are testing at condenser outlet, whereas nozzle inlet diameter equal to discharging tube diameter of condenser and outlet diameter equal to inlet diameter of expansion valve. Additional pressure drop in the nozzle helped to achieve higher performance of the vapour compression refrigeration system. The system is analyzes using the first and second laws of thermodynamics, to determine the refrigerating effect, the compressor work input, coefficient of performance (COP).
Copyright (c) 2023 B Sairamakrishna, T Gopala Rao, N Rama Krishna (Author) https://creativecommons.org/licenses/by-nc-nd/4.0