Department of Mechanical engineering

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Performance of Farmer Producer Organisations in Rajasthan: An Empirical Assessment
(Routledge, 202) Pandey, Ranjan; Sharma, Satyendra Kumar; Routroy, Srikanta
India is predominantly an agrarian economy. According to the recent Economic Survey (2021–22), agriculture and allied sectors continue to be the mainstay of the Indian economy as it is the largest employer of the working population and contributes about 19 to the total gross value added of the country in 2021–22. Unlike the agriculture system in Western Europe, Indian agriculture is dominated mainly by small and marginal farmers, accounting for more than four-fifths of the total landholding size. More recently, due to government intervention, many strategies, including agri-business models, have been developed to tackle 384the marginalisation of farmers by bringing them under one umbrella. With the recommendation of a committee headed by YK Alagh, the formation of Farmer Producer Organisations (FPOs) has become a reality by incorporating a special provision in part IXA of the Companies Act, 1956. In this context, our attempt in this paper is to evaluate the financial performance of FPOs registered in Rajasthan.
The effects of inlet fluid flow nonuniformity on thermal performance and pressure drops in crossflow plate-fin compact heat exchangers
(Elsevier, 1996-10) Ranganayakulu, Chennu
An analysis of a crossflow plate-fin compact heat exchanger, accounting for the effects of two-dimensional nonuniform inlet fluid flow distribution on both hot and cold fluid sides, is carried out using a finite element model. A mathematical equation is developed to generate different types of fluid flow maldistribution models considering the possible deviations in fluid flow. Using these fluid flow maldistribution models, the exchanger effectiveness and its deterioration due to flow nonuniformity are calculated for an entire range of design and operating conditions. In addition to thermal analysis, the pressure drops and their variations are also calculated for these models. It was found that the performance deteriorations and variation in pressure drops are quite significant in some typical applications due to fluid flow nonuniformity
The effects of longitudinal heat conduction in compact plate-fin and tube-fin heat exchangers using a finite element method
(Elsevier, 1997-04) Ranganayakulu, Chennu
An analysis of the crossflow plate-fin, crossflow tube-fin, counterflow plate-fin and parallel flow plate-fin compact heat exchangers accounting for the effect of ‘longitudinal heat conduction’ through the exchanger wall is carried out using a finite element method. The exchanger effectiveness and its deterioration due to the longitudinal heat conduction effect have been calculated for various designs and operating conditions of the exchanger. The results indicate that the thermal performance deterioration of crossflow plate-fin, crossflow tube-fin and counterflow plate-fin heat exchangers due to longitudinal heat conduction may become significant especially when the fluid capacity rate ratio is equal to one and when the longitudinal heat conduction parameter is large.
The combined effects of inlet fluid flow and temperature nonuniformity in cross flow plate-fin compact heat exchanger using finite element method
(Springer, 1997-06) Ranganayakulu, Chennu
An analysis of a crossflow plate-fin heat exchanger accouning for the combined effects of inlet fluid flow nonuniformity and temperature nonuniformity on both hot and cold fluid sides is carried out using a Finite Element Model. A mathematical equation is developed to generate different types of fluid flow/temperature maldistribution models considering the possible deviations in inlet fluid flow. Using these fluid flow maldistribution models, the exchanger effectiveness and its deteriorations due to flow/temperature nonuniformity are calculated for entire range of design and operating conditions. It was found that the performance deteriorations are quite significant in some typical applications due to inlet fluid flow/temperature nonuniformity.
The combined effects of wall longitudinal heat conduction, inlet fluid flow nonuniformity and temperature nonuniformity in compact tube–fin heat exchangers: a finite element method
(Elsevier, 1999-01) Ranganayakulu, Chennu
A finite element analysis of a crossflow tube–fin compact heat exchanger is presented. The analysis takes into account the combined effects of one-dimensional longitudinal heat conduction through the exchanger wall and nonuniform inlet fluid flow and temperature distributions on both hot and cold fluid sides. A mathematical equation is developed to generate different types of fluid flow⧹temperature maldistribution models considering the possible deviations in fluid flow. Using these fluid flow⧹temperature maldistribution models, the exchanger effectiveness and its deterioration due to the combined effects of longitudinal heat conduction and flow⧹temperature nonuniformity are calculated for various design and operating conditions of the exchanger. It was found that the performance deteriorations are quite significant in some typical applications due to the combined effects of longitudinal heat conduction, temperature nonuniformity and fluid flow nonuniformity on crossflow tube–fin heat exchanger.
The combined effects of wall longitudinal heat conduction, inlet fluid flow nonuniformity and temperature nonuniformity in compact tube–fin heat exchangers: a finite element method
(Elsevier, 1999-01) Ranganayakulu, Chennu
A finite element analysis of a crossflow tube–fin compact heat exchanger is presented. The analysis takes into account the combined effects of one-dimensional longitudinal heat conduction through the exchanger wall and nonuniform inlet fluid flow and temperature distributions on both hot and cold fluid sides. A mathematical equation is developed to generate different types of fluid flow⧹temperature maldistribution models considering the possible deviations in fluid flow. Using these fluid flow⧹temperature maldistribution models, the exchanger effectiveness and its deterioration due to the combined effects of longitudinal heat conduction and flow⧹temperature nonuniformity are calculated for various design and operating conditions of the exchanger. It was found that the performance deteriorations are quite significant in some typical applications due to the combined effects of longitudinal heat conduction, temperature nonuniformity and fluid flow nonuniformity on crossflow tube–fin heat exchanger.
The combined effects of longitudinal heat conduction, flow nonuniformity and temperature nonuniformity in crossflow plate-fin heat exchangers
(Elsevier, 1999-07) Ranganayakulu, Chennu
An analysis of a crossflow plate-fin compact heat exchanger, accounting for the combined effects of two-dimensional longitudinal heat conduction through the exchanger wall and nonuniform inlet fluid flow and temperature distribution is carried out using a finite element method. A mathematical equation is developed to generate different types of fluid flow/temperature maldistribution models considering the possible deviations in fluid flow. Using these models, the exchanger effectiveness and its deterioration due to the combined effects of longitudinal heat conduction, flow nonuniformity and temperature nonuniformity are calculated for various design and operating conditions of the exchanger. It was found that the performance variations are quite significant in some typical applications.
The combined effects of wall longitudinal heat conduction and inlet fluid flow maldistribution in crossflow plate-fin heat exchangers
(Springer, 2000-05) Ranganayakulu, Chennu
An analysis of a crossflow plate-fin compact heat exchanger, accounting for the combined effect of two-dimensional longitudinal heat conduction through the exchanger wall and nonuniform inlet fluid flow distribution on both hot and cold fluid sides is carried out using a finite element method. Using the fluid flow maldistribution models, the exchanger effectiveness and its deterioration due to the combined effects of longitudinal heat conduction and flow nonuniformity are calculated for various design and operating conditions of the exchanger. It was found that the performance deteriorations are quite significant in some typical applications due to the combined effects of wall longitudinal heat conduction and inlet fluid flow nonuniformity on crossflow plate-fin heat exchanger.
Fuzzy controller development from information granules for a heat exchanger
(NISCAIR, 2000-07) Dasgupta, Mani Sankar
This paper discusses the experimental results of on-line fuzzy control of a heat exchanger unit. Fuzzy controllers are a class of model independent controllers. which use common sense logic, expressible in linguistic form and is more amenable to human way of decision-making, A collection of information granules, regarding the process under study, is documented first. Using the some, the steps of formation and justification of the fuzzy look-up table is demonstrated. An efficient fuzzy control is established using multiple look-up tables. These tables are further adapted to accommodate conflicting control demands of 'low overshoot' and 'small rise time', An algorithm for on-line table switching is also proposed.
The Effects of Inlet Temperature Nonuniformity in a Crossflow Plate-fin Heat Exchanger
(IHTC, 2002) Ranganayakulu, Chennu
A finite element analysis of a cross-flow plate-fin compact heat exchanger is presented. The analysis takes into account the effects of non-uniform inlet fluid temperature distributions on both hot and cold fluid sides. Temperature mal-distribution models are generated considering possible deviations in fluid temperatures. Using fluid temperature mal-distribution models, exchanger effectiveness and its deterioration due to the effects of temperature non-uniformity are calculated for various design and operating conditions of the exchanger. It was found that the performance deviations are quite significant in some typical applications due to the temperature non-uniformity on a cross-flow plate-fin heat exchanger.
Computer aided design and manufacture of streamlined extrusion dies
(Elsevier, 2003-07) Srinivasan, P.
Extrusion is one of the widely used metal forming processes. The extrusion process is carried out conventionally using a shear faced die, but shear faced dies have many practical problems such as a dead metal zone, more redundant work, breaking of whiskers and above all the design of a shear die is done based on experience. To eliminate the above problems, a new approach of designing the die known as a streamlined die is tried here. The streamlined extrusion die is designed based on the principle of constant area reduction over the length of the die. In this, a uniform flow of metal is ensured from the surface to the core and this can be a more scientific approach of die design. Many methods are available in the literature to design the streamlined extrusion die such as cubic polynomial curves, the area mapping technique, the line-mapping technique and the use of a genetic algorithm. For solving the problem of die design Stokes’ theorem is suggested, but a new approach of transforming the peripheral point on the surface of a cylinder to the corresponding point on the extruded square is obtained by an analytical method. An attempt is made to identify an analytical solution for designing a streamlined extrusion die for a square cross-section.
Performance value analysis for the justification of world-class manufacturing systems
(World Scientific, 2004) Sangwan, Kuldip Singh
World-class manufacturing systems (WCMS) has attracted the attention of industries all over the world. The perceptible impact of WCMS lies in attaining the far reaching world-class standards. Attempts have been made to examine WCMS for the feasibility in Indian industries. The present work describes a performance value analysis for the justification of WCMS for Indian industries.
A review of wind energy developments in India
(Inder Science, 2004) Soni, Manoj Kumar
Climate change, dwindling reserves of fossil fuels and shortage of electricity have prompted the government to give an impetus to renewable energy sources. Wind energy, with an average growth rate of 30%, is the fastest growing source of renewable energy in the world. India has a potential capacity of over 45,000 MW out of which 1869 MW has been extracted from this eco-friendly source. India stands at fifth position in the world in wind energy development. Policy initiatives and fiscal initiatives for realisation of the estimated potential already exist. This paper discusses an overview of wind assessment, monitoring, development and environmental impact in India. Financial interventions and state policies on commercialisation are also presented with a view to identifying the barriers for further commercialisation.
Bubble formation with pool boiling on tubes with or without basic surface modifications for enhancement
(Elsevier, 2004-04) Ranganayakulu, Chennu
Bubble formation is investigated on a single, horizontal copper tube (D=25.4 mm) before and after applying surface modifications in the form of macrocavities with comparatively simple shapes (size: 200 × 100 μm on the tube surface and 50 μm in depth) in order to link bubble formation and heat transfer to the geometric features of the cavities. Two kinds of cavities exist in parallel, one with reduced mouth width (so-called “main structure”) and one without this reduction (“secondary structure”). Pool boiling experiments with different organic liquids have been performed with variation of heat flux and saturation pressure. The resulting bubble formation on the tubes with and without surface modifications is discussed in terms of characteristic parameters such as local distribution and temporal activation behavior of the nucleation sites for bubble formation at active nucleation sites (“primary bubbles”) or for bubbles released from the macrocavities (“secondary bubbles”).
Multi-attribute decision models for justification of cellular manufacturing systems
(Inder Science, 2004-11) Sangwan, Kuldip Singh
There is a general challenge offered to the field of engineering economics by the introduction of advanced manufacturing systems. Typically, the traditional approaches do not account for the significant intangible benefits offered by cellular manufacturing systems. In this paper, an attempt has been made to overcome the above-mentioned deficiencies by presenting two multi-attribute decision models – analytical hierarchy process and performance value analysis – for the justification of CMS. The usefulness of the proposed models is demonstrated through a case situation.
Differential evolution algorithm for supply chain inventory planning
(Emerald, 2005) Routroy, Srikanta
This paper discusses the inventory planning of a supply chain, which consists of a manufacturer, distributor and retailer.
A designer workbench with real-time capture and reuse of information on product evolution and rationale
(ICED, 2005) Kota, Srinivas
Product Life Cycle Management promises management of all intellectual assets generated for all life cycle phases of a product [1]. This includes supporting capture and structure of information generated about an evolving product during the PD process [1]. Many structures for product information [3, 4, 5, 6] and rationale information [7, 8] have been suggested, and some turned into a tool, e.g. [7, 8]. However, a practical tool for automated capture and structure of product information including rationale information without interrupting the working of the designer, especially as a product evolves through the PD process, is yet to be developed. The framework reported here has been developed by analysing the proceedings from design experiments and literature to capture, segregate and store the information generated in product design without interrupting designer. The main features of the framework are implemented into the preliminary version of a software tool and evaluated for the ease of use and reuse for designers and re-designers (re-users of rationale). The main functions currently supported are: creation and modification of a three-dimensional assembly, exploring the details of a version tree and product structure, and, exploring the events via video/audio clips attached to the version tree.
Design and development of streamlined extrusion dies a Bezier curve approach
(Elsevier, 2005-04) Srinivasan, P.
Conventional shear dies used for extrusion of metals suffer from many problems. Attempts are made to improve the die design in many ways. Streamlined extrusion dies are considered to be better than shear dies. Streamlined extrusion dies are designed by various methods such as: (i) polynomial equation based dies (ii) area and line mapping technique (iii) analytical method. A new approach of designing streamlined dies using Bezier curve is attempted in this paper. Theoretical calculation on the total extrusion pressure for various friction factors is carried out. Comparison is made between Bezier curve based die and polynomial equation based dies. It is observed that the Bezier curve based die for the given takes lower extrusion pressure compared to other dies, for constant friction factor and area reduction.
Heat transfer from horizontal tubes in pool boiling: influence of three-dimensional heat conduction in the wall of the evaporator tube—a finite element analysis
(Springer, 2005-10) Ranganayakulu, Chennu
In pool boiling, the electrically heated tube releases the energy non-uniformly to the liquid, due to different surface roughness and flowing liquid. The heat transfer coefficient therefore varies with axial and azimuthal position on the tube. Hence a finite element analysis has been carried out on a horizontal 1in. copper tube for evaporation in pool boiling for three-dimensional conduction heat transfer. A test tube has been made with different surface structures, tested and analysed for heat conduction effects. It has been observed that significant amount of heat flows in azimuthal and axial directions in addition to the heat flow in radial direction.
Reliability Based Approach to Manipulator Parameter Design
(BITS-Pilani, 2006) Rout, Bijay Kumar
The work illustrates simulation approach for parametric design and optimizing the performance of a 2-DOF RR planar manipulator. Using dynamic and kinematic models of a manipulator different performance measures for the manipulator are obtained for different combination of parameters with effect of noise incorporated to imitate the real time performance of the manipulator. A novel approach has been used to model, the otherwise difficult to model, noise effects. The data generated during simulation for various parameter combinations are utilized to analyze the statistical significance of kinematic and dynamic parameters on performance of manipulator using ANOVA technique. Optimal parameter combinations, which gave optimum performance measures, for a point in workspace are obtained and compared.