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In comparison to other thermal power cycles, gas turbine based energy conversion cycles exhibit superior thermodynamic performance as well as reduced emission. Gas turbine manufacturers and research & development (R&D) organizations are working on modification in basic gas turbine (BGT) cycle, which are intended to improve the basic gas turbine cycle thermodynamic performance and reduce emissions. The present work reports a comparison of thermodynamic performance, NOx and CO emission for basic and intercooled gas turbine (IcGT) cycles. Various cycle operating parameters such as compressor-pressure-ratio (rp,c), combustor-primary-zone-temperature, equivalence-ratio, and residence time of gas turbine based cycles has been examined. IcGT cycle exhibits higher gas turbine specific work and gas turbine efficiency in comparison to BGT cycle for the same rp,c and turbine rotor inlet temperature.

This paper focuses on the thermodynamic analysis of Solid Oxide fuel cell (SOFC). In the present work the SOFC has been modeled to work with internal reforming of fuel which takes place at high temperature and direct energy conversion from chemical energy to electrical energy takes place. The fuel-cell effluent is high temperature steam which can be used for co-generation purposes. Syn-gas has been used here as fuel which is essentially produced by steam reforming of methane in the internal reformer of the SOFC. A thermodynamic model of SOFC has been developed for planar cell configuration to evaluate various losses in the energy conversion process within the fuel cell. Cycle parameters like fuel utilization ratio and air-recirculation ratio has been varied to evaluate the thermodynamic performance of the fuel-cell. Output performance parameters like terminal voltage, cell-efficiency and power output have been evaluated for various values of current densities.

Auto industry faces twin problems of pollution and exorbitant rise in petroleum prices. These two problems are best addressed by reducing the weight of the body structure. Under the current technology reduction in weight of an automobile is accomplished by replacing metal with synthetic composites. Reduced weight of the body structure economizes on fuel consumption but this method does not solve the problem of containing pollution because synthetic fibers are used. However, the authors in this paper suggest the use of Hybrid Composites which substantially reduces body weight of an automobile and simultaneously addresses the pollution problem. This is done by substituting natural fibers for synthetic fibers. From an engineering stand point Natural Fibers in the form of Banana Fibers, Sisal, Jute, Coir could prove to be potential competitors to synthetic fibers currently used in polymer composites such as E-Glass, S-Glass, Basalt, Carbon/ Graphite Fibers, and KEVLAR-49.

Energy generation and its use affect the surrounding environment. About sixty five percent of the energy comprises of global anthropogenic green house gas emissions which are renewable. Reduction of this emission must necessarily begin with action targeted shift of energy sources that are renewable. Out of the various sources of renewable energy biomass and specifically agro-biomass has a lot of potential as it can be utilized in the existing energy conversion systems with minor modification. Biomass can be utilized in energy conversion system by co-firing in a modern coal fired power plant with biomass content up to 10% by weight. The combustion efficiency of biomass feedstock can be about 10% lower than that for coal. Biomass can also be combusted in a dedicated power and combined-heat and power (CHP) plant that is typically smaller in size and of lower efficiency of up to 35%. In cogeneration mode the efficiency may go up to 90%.

Compacted-graphite iron (CGI) has been promoted as the material of choice for diesel engines as popular alternatives to conventional gray cast iron. CGI has higher strength and elastic modulus than gray iron but retains the damping properties, thermal conductivity, and castability of gray iron. But for all the advantages of higher strength and wear resistance offered by CGI, it is precisely these properties that make it difficult to machine. Rotary-insert tooling is a patented boring tool that shows promise for reducing the machine horsepower needed for cylinder boring operations. Holes with large diameters are usually bored with boring heads having multiple inserts. The boring heads are used as alternatives to single point boring bars. The diameter of the boring head is equal to the finish diameter of the hole, and inserts are symmetrically distributed around the circumference of the boring head in order to provide force cancellations in the plane perpendicular to hole axis.

Mechanical properties of porous materials such as bones for example are controlled by the geometry and structure of the pore space. Traditionally, most attempts to understand the effect of pore structure on mechanical properties have assumed that the pores can be modeled as ellipsoids Eshelby [9] etc. Nevertheless pictures taken by SEM show that pore shapes are never as simple as circles or ellipses. But the use of real pore shapes in the modeling process has been hindered by the lack of analytical solutions for these shapes. Zimmermann [24] suggested that the pore compressibility Cpc scales approximately with where A is the area of the pore space and P is the perimeter surrounding the pore space. Forcing this scaling law to be exact for a circular hole leads to the approximation . Zimmerman [25] showed that this approximation has an error of less than 8% for all hypotrochoids and an error of about 23% for thin, crack-like pores, which he suggested might be the "worst-case" shape.

Drilling compound hole is very common material processing operation in engineering industry. In this special machining process before drilling the hole the part is rotated about an auxiliary axis parallel to one of the reference axes. Accuracy of the drilled hole is paramount in several applications such as in cylinder head and some other applications of bone surgery. Inaccuracy in hole axis may result in the loss of engine efficiency in the case of Cylinder Head or unsuccessful bone surgery. In the previous papers Murty et al. [8], [9] the algorithms developed had restricted application. In the first paper the tool was restricted to move in vertical plane and WY-plane was considered as reference plane. In the second paper the tool movement was unrestricted in space but the WY-plane was considered as reference plane and the skew error was assumed only in WY-plane.

This paper presents a novel technique for the kinematic analysis of planar and spatial open chain systems, called the Incidence and Transfer Method (IT), which is based on the incidence matrices associated with the edge-oriented graph attached to the mechanism and the transfer joints. Relative to such joints, a set of independent equations can be automatically generated for the efficient computation of manipulator's joint positions and velocities. Kinematics of open chain manipulators with common joints such as revolute (R), prismatic (P), cylindrical (C), and helical (H) can be solved by using the sparse matrices derived from the manipulator's graph model. Complete kinematic equations are obtained in matrix form using a base of circuits from a cycle matroid. The proposed method has general applicability and can be employed for systems with any number of links and degrees of freedom, as illustrated by the numerical example presented.

Although the performance of CNC machines is accurate, unavoidable human errors at the part loading position have serious repercussions on engine performance. In the present paper the authors would like to develop an algorithm for error compensation when the tool movement is unrestricted in space. The new solution algorithm will be in terms of the known initial system variables such as the part loading errors, drill tool inclinations, location of spindle etc. This modified paper employs the same principles of inverse kinematics as done in the earlier paper wherein a faulty compound-hole angle axis in space caused by the translational and rotational errors at the part loading position is identified with an imaginary true axis in space by enforcing identity through a modified machine axes taking into effect inclination of the drill tool in space. In the absence of any specific application, this algorithm is verified on Solid Works a commercial CAD tool and found to be correct.

Proper valve angles and concentric valve seats are critical to performance of an engine. If the valve seat were not right, the valve is not going to seat properly resulting in reduced power output. Although the performance of CNC machines is accurate, unavoidable human errors at the part loading position have serious repercussions on engine performance. A solution algorithm presented in this paper employs the principles of inverse kinematics wherein a faulty compound-hole angle axis in space caused by the translational and rotational errors at the part loading position is identified with an imaginary true axis in space by enforcing identity through a modified machine axes.