Varun Goel

Varun Goel
National Institute of Technology, Hamirpur | NIT Hamirpur · Department of Mechanical Engineering

PhD

About

159
Publications
95,997
Reads
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6,236
Citations
Additional affiliations
August 2007 - present
National Institute of Technology, Hamirpur
Position
  • Professor (Assistant)
August 2007 - May 2019
National Institute of Technology, Hamirpur
Position
  • Professor (Assistant)

Publications

Publications (159)
Article
The demand for fresh water in today's world is rising continually due to the increase in population and rise in industrial developments. Solar Desalination is one of the sustainable and renewable ways to convert brackish or salty water into fresh water. The use of solar desalination contributes towards decarbonization, mitigation of CO2 and other a...
Article
As an emerging technology, photovoltaic (PV) panels have made a vital energy source to meet increased energy consumption demand and to replace the associated scarcity of traditional energy resources. PV modules have electrical efficiency from 4 to 26%, depending on their materials. The PV panel transforms about 50–60% of total solar radiation into...
Article
India has many renewable and sustainable energy sources like solar, wind, hydro, biomass energy etc. In India, the renewable energy (RE) growth rate has not touched a benchmark due to various barriers in its development pathway. Yet, it is difficult to identify the severity of barriers that mostly hampers the growth of RE technologies. A systematic...
Article
The objective of this article is to study the work carried out in heat transfer augmentation using active and passive techniques. A comprehensive summary of the work is highlighted to showcase the strength of these techniques in terms of enhancement in heat transfer. In this work, research studies done in the area of electrohydrodynamic, magnetic f...
Article
Solar-air Heater (S-AH) is the simplest device that helps in converting solar-energy to heat and the extracted heat can either be used for heating space, or drying crops, etc. In the present investigation, the jet-impingement technique is employed and the effect of relative-jet diameter is analysed on the performance of S-AH. A commercial software...
Article
The world’s annual powder traders expected to reach a figure of 13.20 MT by the end of 2024; expanding at a growth rate higher than 4% during the period 2019–2024. Also, skim / whole milk powder production recorded a steep rise of 50% in last three decades. In view of energy-intensive operations associated with milk powder production activity; it’s...
Article
Conversion of solar energy into thermal energy using solar collectors is the most promising way for its applicability. Artificial roughness applied underside of the solar heat-collector is a preferably advantageous technique to enhance the solar air heater performance. In the present study, a comprehensive parametric analysis of the multi-V-ribs-wi...
Article
Full-text available
In the present study, the heat transfer and thermal performance of a helical corrugation with perforated circular disc solar air-heater tubes are predicted using a machine learning regression technique. This paper describes a statistical analysis of heat transfer by developing an artificial neural network-based machine learning model. The effects o...
Article
The use of solar air heaters (SAH) for the collection and effective utilization of solar radiations for thermal applications is widely reported in the literature. The current article aimed to present a comprehensive literature review on history, fundamentals and the latest advancement reported in the field of solar thermal air heating systems. Vari...
Article
Rapidly depleting conventional fuel reserves had prompted research on alternative fuels for diesel engines as diesel is most widely used in public transportation all over the world. The environmental consequences of using diesel are also encouraging to shift our focus towards alternative fuels. The nitrogen oxides (NOx) and smoke are the significan...
Article
A solar air heater (SAH) is a heat exchanger that is capable of converting radiations (solar) into thermal energy, which is further utilized for heating purposes. But due to poor thermal conductivity of air, SAH has poor thermal performance. Roughness is one of the effective techniques used to improve the performance of SAH. Two different roughness...
Article
The working medium is air in a solar air heater (SAH) and because of its low heat-transfer coefficient, SAH results in poor performance. By placing artificial roughness over the heat-collector plate, the performance of a SAH can be improved significantly. The improvement in thermal and hydraulic performance by providing multiple-arc-rib roughnesses...
Article
The thermal energy available in the form of solar radiation is collected and converted into heat with the help of a solar air heater. The flow and thermal characteristics change significantly with the cross-sectional shape of the flow passage. The effect of hemispherical dimple-cavities that were employed over the heat-collector plate has been anal...
Article
Baffles are used for heat transfer enhancement in heat exchanger tubes. However, they also increase the friction factor in the flow channel. Perforation in baffles further augments the heat transfer. Moreover, it was also noticed that the perforations in the baffles strongly reduce the associated pressure drop in the tube. Some novel ideas for baff...
Article
Roughness is one of the effective and promising method to improve heat transfer through the solar air heater. The cross-sectional shape of roughness provided on the absorber plate shows a strong influence on solar air heater performance. In this work, the influence of various roughness-elements (such as semi-circular, circular, triangular, square,...
Chapter
Carbon footprint is the process in which the effect of estimation of carbon emission in a particular system/process is evaluated from its origin (cradle) to its death (grave). In industry, carbon emissions released due to various activities like using materials, transportation, utility equipment etc. Carbon footprint helps us in the identification...
Chapter
The main goal of sustainability is to focus on fulfilling the present needs of population with the ability to produce resources to fulfill the needs in future. With growing concern for the environment, sustainable development has become one of the primary goals of all nations throughout the world. In the same track, the need of sustainable assessme...
Article
Full-text available
Formaldehyde is one of the vital chemicals produced by industries, transports, and domestic products. Formaldehyde emissions adversely affect human health and it is well known for causing irritation and nasal tumors. The major aim of the modern indoor formaldehyde control study is in view of energy capacity, product selectivity, security, and durab...
Article
The performance models for high temperature metallic recuperators considering one and two dimensional heat transfer is presented. In one dimensional model, an explicit expression to represent the effect of both the temperature and product of partial pressure and mean beam length on the emissivity is developed using emissivity charts. The effect of...
Article
The low heat transfer coefficient of air causes poor performance of solar heat exchanger. Protrusion shaped roughness has been considered in the present investigation to enhance the performance of solar heat exchanger. The heat-exchanger designed has triangular cross-sectional flow passage and it is embedded with heater assembly for creating requir...
Article
Roughness is an effectual way to augment heat transfer in solar air heater (SAH). Multiple arcs (with gap) type of roughness has considered in this work and experimentation is performed to determine their effect on thermo-hydraulic performance of rectangular channel SAH duct. The experimentation is performed to analyze the effect of different param...
Article
Hydropower is considered as one of the most convenient and popular renewable energy technologies and its capacity is growing rapidly throughout the world. Its rapid deployment also comes up with various environmental issues which cannot be neglected at a glance. Previous studies had imposed questions about its sustainable nature and now it becomes...
Article
In the present investigation, experiments were conducted to perceive the influence of S shaped roughness element with gaps on flow and heat transfer (HT) characteristics. The studied parameters were relative roughness-width (W/w) ranges from 1-4 (4 different values), relative roughness-pitch (P/e) ranges from 4-16 (4 different values), arc angle (α...
Article
The plate fin heat exchangers usually have either rectangular or triangular shaped flow passage. In comparison to triangular flow passage, rectangular flow passage gives comparatively higher heat transfer at the cost of higher pumping power. In the present investigation, flow passage is modified by rounding the corner of triangular passage to inves...
Article
Solar air heater is widely used for heating and drying applications. Many techniques have been used to improve the performance of a solar air heater but the most common technique is surface roughness in which ribs are provided over the absorber plate. In the present article, multiple-arc shaped (three arcs) rib roughness is provided on the undersid...
Article
Solar air heater is widely used for heating and drying applications. Many techniques have been used to improve the performance of a solar air heater but the most common technique is surface roughness in which ribs are provided over the absorber plate. In the present article, multiple-arc shaped (three arcs) rib roughness is provided on the undersid...
Article
Fossil fuel consumption provides a negative impact on the human health and environment in parallel with the decreased availability of this valuable natural resource for the future generations to use as a source of chemical energy for all applications in energy, power, and propulsion. The diesel fuel consumption in the transport sector is higher tha...
Chapter
As the world is shifting towards renewable energy power generation it becomes important to explore the correct picture of renewable energy technologies. Today every nation is ramping up investments in power sector and trying to increase its installed capacity of power generation through renewable energy due to benefits like less greenhouse gas emis...
Article
The present investigation focuses on need of bio-based lubricants which are biodegradable and environmental-friendly along with improved oxidative stability. The global demand for lubricants is expected to increase as the demand for engine oil for new motor vehicle increases with the increase in number of vehicles. The depleting nature of mineral o...
Article
The sharp corner significantly affects the flow through triangular duct. In the corners, flow gets stagnant and results in poor heat transfer. Therefore, in the present study, one corner of the duct is kept rounded with variable curvature radius values (Rc). The curvature radius is selected in such a way that, it varied from the minimum value (i.e....
Article
The results obtained on wear assessment from a compression ignition (CI) engine fueled with a blend of 70% amla seed biodiesel (AB) and 30% eucalyptus oil (EU) on volume basis (called AB70EU30). The results showed stable engine operation and good operability of the engine-fuel system with the binary biodiesel fuel blend. The feasibility of this ble...
Article
This paper presents lubricating oil performance in a compression ignition (CI) engine fueled with a binary fuel blend of 70% aamla seed oil biodiesel and 30% eucalyptus oil (EU) on volume basis. This blended fuel was stable and congruent with engine-fuel system. Initially, the engine was operated with normal diesel fuel as per standard endurance te...
Article
The ribbed three-dimensional solar air heater (SAH) model is numerically investigated to estimate flow and heat transfer through it. The numerical analysis is based on finite volume approach, and the set of flow governing equations has been solved to determine the heat transfer and flow field through the SAH. For detailed analysis, rib chamfer heig...
Article
The turbulent flow heat transfer and friction penalty in triangular cross-sectional duct is studied in the present article. The sharp corners of the duct are modified by converting it into circular shape. Five different models are designed and fabrication. The heat transfer through all the models is investigated and compared with the Model-1 (i.e....
Article
Solar air heater (SAH) is a device used to convert sun radiations into heating applications. To improve its performance, the heat absorbing side of SAH is modified with the ribs called roughness. The flow characteristics and augmentation of heat due to square shaped ribs in SAH having triangular cross-sectional passage has been simulated using comp...
Article
Energy saving is a vital element in today's scenario. Earth Air Heat Exchangers (EAHE) is a technique that promotes energy savings. EAHE is a non-conventional technique that uses the earth's underground heat for space cooling/heating. In this article, review of different combinations of EAHEs is presented. The review presents an apprehensible summa...
Article
In the present time, need of biogenic lubricants is the focusing area which will be biodegradable, avirulent and eco-friendly. Current experimental tests depict the effect of ‘Phyllanthus emblica’ a non-edible feedstock through pin on disc tribo tester. Tests were conducted to evaluate the impact of 0, 10, 20 and 30 % blending of Phyllanthus emblic...
Article
Consumption of fossil fuels is an important issue which is to be addressed for better tomorrow due to its dreadful implications on the environment and its depleting nature is also a concern. Hence, the need of more diversified research in alternate sources arises, even to the point of complete elimination of diesel from compression ignition (CI) en...
Chapter
Full-text available
In this study, a theoretical analysis of food processing (e.g., solar drying), worldwide cooking pattern, and cooking methods by using the solar energy has been reviewed. Solar food processing method is applied as direct absorption, air heater, and a combination of direct and indirect drying by solar radiation. Therefore, this process is one of the...
Article
Solar air heater (SAH) absorbs thermal radiations from Sun and utilizes it to heat air. The thermal performance of SAH can be improved by using ribs on the absorber plate. In this paper, rectangular geometry of ribs is considered over the absorber plate. The fluid flow characteristics and heat transfer in ribbed triangular duct (with an apex angle...
Article
Biodiesel is one of the most rapidly emerging fuels that promise to replace diesel in the near future. However, there are a number of challenges that lay ahead, both in terms of technical aspects as well as economic and replacement policies. If it is used in a regular engine, biodiesel does not give the same performance as diesel. This follows the...
Article
The experiments were performed to analyze the influence of apex angle on thermal and hydraulic characteristics of triangular duct for Reynolds number range from 2000 to 16,000. Four different triangular ducts of apex angle 30°, 60°, 90° and 110° were fabricated for the experimentation. The one side of the duct is roughened with dimple shaped roughn...
Article
Biodiesel can be considered to be the most capable alternate fuel for partial or complete replacement of the fossil fuel. Previous studies on biodiesel-oil blends have demonstrated that the use of double biofuels in engine can be a promising aspect for the complete elimination of diesel from compression-ignition (CI) engines. But its use increases...
Article
The consciousness of deteriorating fossil fuels and the adverse impact of its consumption on human health have diverted the research towards alternate energy sources. Biodiesel seems to be the best promising alternate fuel for diesel engines as it has potential to partially or completely eliminate diesel from compression ignition (CI) engine. Sever...
Article
The fluid flow characteristics and heat transfer in triangular duct solar air heater (SAH) has been studied experimentally and numerically for Reynolds number range from 4000 to 18000. In the present paper, three different models of triangular duct solar air heater were considered, namely, Model 1 with simple triangular duct, Model 2 with rounded c...
Article
Purpose The computational fluid dynamics (CFD) based study on semi-circular rib roughened equilateral triangular duct has been carried out to investigate heat transfer, friction factor, and thermal enhancement factor. The analysis is carried out by simulating problem in ANSYS (Fluent). The Reynolds number in the study varies from 4,000 to 24,000. N...
Article
The amount of pressure on the automotive industry, competition facing from other automotive manufacturers, or the rules and regulations imposed by administrative bodies, biodiesel is turning out as a favourite alternative for almost all-ongoing research in the area. In the present experimental study, aamla biodiesel is used in different volumetric...
Article
An experimental study has been carried out to analyze the effect of inclined ribs used as roughness element on heat transfer along its friction characteristics. The roughness parameters include relative roughness pitch (P/e) ranges from 4–16, relative roughness height (e/Dh) ranges from 0.021–0.043 and angle of attack (α) ranges from 30°-75°. The R...
Article
The heat transfer can be improved by providing artificial roughness on absorber plate of the solar air heat. Many studies are available on circular, semi-circular, triangular and rectangular rib roughened solar air heater. But in present study heat transfer enhancement by providing elliptical ribs on absorber plate was analyzed by developing CFD...
Chapter
When humankind began to store food or other items for next-day use, packaging in its primitive form emerged. In ancient times, leaves and bushes were used. By using high-end lightweight, durable, and cheaper material, today’s packing industry has evolved exponentially. The industry is continuously searching for packaging solutions that have better...
Article
In this present article an experimental study has been carried out on heat transfer and friction factor in rectangular channel which is having multiple-arc shaped with gaps as roughness element. The investigation encompassed Reynolds number (Re) ranges from 2100 to 21,000 (7 values), relative roughness height (e/D) ranges from 0.016 to 0.044 (4 val...
Article
The depleting natural resources, primarily petroleum that has been the backbone of fuel industry is finding itself at loss to answer the questions of our future needs. This has led researchers to venture into the area of biodiesel since it is the next best contender to replace diesel in the immediate future. This is so because biodiesel has charact...
Article
Heat transfer enhancement is an important matter of concern for energy conservation and also beneficial from economic point of view. The use of passive devices like twisted tapes, roughness elements, wires inserts etc. are effective methods of heat transfer augmentation. Many research studies on different types of twisted tapes geometries to increa...
Article
Duct geometry is one of the important factors which influence the heat transfer in laminar and turbulent flow conditions. Along with heat transfer, pumping power required for fluid flow through a duct is also an important concern in industries. In most of the industrial applications, the flow is turbulent in nature. Many studies were carried out to...
Article
The force convective heat transfer in an equilateral triangular duct of different wall heat flux configurations was analysed for the laminar hydro-dynamically developed and thermally developing flow by the use of finite volume method. Unstructured meshing was generated by multi-block technique and set of governing equations were discretized using s...
Article
Radiation plays a dominant role in combustion space heat transfer. It is composed of three components, namely gaseous species radiation, soot radiation and crown surface radiation. The basis for model validation and the subsequent study of furnace operation is the spatial variation of radiant heat flux. Hayes and colleagues carried out measurements...
Article
An experimental study has been carried out for the heat transfer and friction characteristics for arc shaped roughness element used in solar air heaters. Duct has an aspect ratio (W/H) of 11, relative roughness pitch (p/e) range of 4–16, relative roughness height (e/D) range of 0.027–0.045, Reynolds number (Re) range of 2200–22,000 and arc angle (α...
Article
In this study, effect of roughness parameter on heat transfer and pressure characteristics has been studied. Multiple arc-shaped roughness with gaps was used as roughness element in this study. This roughness geometry was created on the underside of plate. The selected parameters were based upon operating conditions and practical feasibility in sol...
Article
Due to depletion of fossil fuels, concerns about energy security and global warming make renewable energy resources more attractive. In this regard, using biodiesel seems to be a possible feasible source of energy for transportation. To decrease dependency on fossil fuels, it is imperative to replace diesel by biodiesel completely in order to mitig...
Article
In this present study experimental investigation has been carried out for roughened double pass solar air heater. The respective variation in other parameters like relative roughness pitch (p/e), relative roughness height (e/Dh) and angle of attack (α) were 5–20, 0.022–0.044 and 30°–75° respectively. The effect of roughness and operating parameters...
Article
Due to depletion of fossil fuels, concerns about energy security and global warming make renewable energy resources more attractive. In this regard, using biodiesel seems to be a possible feasible source of energy for transportation. To decrease dependency on fossil fuels, it is imperative to replace diesel by biodiesel completely in order to mitig...
Article
Erosion of hydro turbine components is a complex phenomenon which depends upon different parameters such as silt size, silt concentration, jet velocity, hardness of silt particles, properties of base materials, jet diameter and operating hours of turbine. Several investigations have studied the effect of these parameters on erosive wear. In the pre...
Article
There is an imperative need to ensure biodiesel’s long-term sustainability to fulfil the quest for renewable fuel resources. The technical problems which are correlated with the use of higher blends of fatty acids methyl esters in diesel engine need to be taken into account in order to avail the environmental and social advantages of biodiesel. The...
Article
Full-text available
Air-conditioning is a basic tool to provide human thermal comfort in a building space. The primary aim of the present work is to design an air-conditioning system based on vapour absorption cycle that utilizes a renewable energy source for its operation. The building under consideration is a classroom of dimensions 18.5 m × 13 m × 4.5 m located in...
Chapter
All buildings have a specific lifetime which can be divided as construction, operation, and demolition phases. A lot of energy and capital are required in the construction phase of a building inasmuch as a large variety of materials is required for building construction. A high amount of waste material is generated in the construction and demolitio...
Article
In this paper, a simulation model is developed to optimise the configuration of a hybrid photovoltaic-battery-diesel system with the objectives to minimise its Life Cycle Cost and CO2 emissions from the system. The decision variables included in the optimisation model are the total area of photo voltaic arrays, number of PV modules of 600 Wp, diese...
Article
This paper investigates the sliding wear behaviour of three different hybrid composites. Each hybrid composite consisted of two fillers. In the present study, combination of Cenosphere along with SiC and Al2O3 has been undertaken. Other factors such as applied normal load and sliding speed are also considered. Taguchi design of experimental techniq...
Article
Full-text available
In this study, the effect of different reinforcements on sliding wear behaviour of aluminium matrix composites has been investigated. The reinforcements used are SiC, Al2O3 and cenosphere. Taguchi design of experimental technique has been used to design and to find out the effects of percentage reinforcement, applied normal load, sliding speed and...
Article
Silt particle laden flow through hydro turbine components causes erosion to the surface which comes in contact with it. Silt size, silt concentration, velocity of flow, properties of silt materials and operating hours of turbine plays a vital role in damaging the turbine components. Efficiency of the turbine decreases with increase in erosive wear....
Article
This paper investigates the sliding wear behaviour of nanoparticle-filled aluminium matrix nano-composites (AMNCs). Two different nano-reinforcements undertaken for this study are SiC and Al2O3. The percentage reinforcement is also varied from 0.5 to 1.5 wt%. For investigating the wear behaviour, factors such as applied normal load, sliding speed a...
Article
The main objectives of the present work are firstly to study and compare the thin layer drying characteristics of fenugreek leaves by open sun and solar drying methods, and secondly to select a mathematical model for describing the drying process under open sun and solar drying of fenugreek leaves using thin layer drying models available in the lit...
Article
In this present experimental investigation the effect of geometrical parameters of multiple arc shaped roughness element on heat transfer and friction characteristics of rectangular duct solar air heater having roughness on the underside of the absorber plate have been studied. The parameters were selected on the basis of practical considerations a...
Article
Silt particles passing through hydro-turbine components cause erosion to the surface which comes in contact. Silt size, silt concentration, velocity of flow, properties of base materials and operating time of the turbine play a vital role in the damage of hydro-turbine components. Several attempts have been carried out to study the effect of these...
Article
Full-text available
In this paper, the flow field of fluid and trajectory of particle are modeled using FLUENT 12.0. In this software, continuity, momentum and particle flow equations are discretized using the Finite Volume Method (FVM) to calculate the pressure and velocity distribution in the flow domain. A Reynolds number of a value up to 1000 is used to view the f...
Article
Diminishing resources, alarming pollution levels and escalating price associated with the application of diesel in compression ignition engine have forced scientific community throughout the world to conduct several experiments for the evaluation of biodiesel (BD) as a substitute for diesel. Due to difference in the physical and chemical properties...
Chapter
The sugar industry plays a vital role in the world’s economy. It also affects the environment directly and indirectly; hence, greenhouse gas (GHG) emission estimation and energy savings in the sugar industry are very important. To improve the efficiency of the plant and analyze the life cycle energy usage and emissions from the sugar industry, a co...