[15] viXra:1601.0335 [pdf] submitted on 2016-01-30 09:06:22
Authors: Ch Sreenivasa Rao, AVSSKS Guptay, K Ramanarasimhaz
Comments: 10 Pages.
Pulsating Heat Pipe (PHP) is a two phase passive heat transfer device for low temperature
applications. Even though it is a simple,
exible and cheap structure, its complex physics has
not been fully understood and requires a robust, validated simulation tool. In the present work
the basic theoretical model by H.B. Ma et al[11] has been updated with the inclusion of capillary
forces in order to characterise the pulsating
ow under the in
uence of various non dimensional
quantities. The mathematical model is solved using explicit embedded Range-kutta method
and proved that the Poiseuille number considered in the numerical analysis assumes more
signicance since it includes
ow characteristics, geometry and
uid properties of a PHP.
Category: General Science and Philosophy
[14] viXra:1601.0334 [pdf] submitted on 2016-01-30 09:07:44
Authors: Mr. Devendra N. Chaudhari, M.R.Phate
Comments: 23 Pages.
In vibration human body is unied and complex active dynamic system. Lumped parameters
are oered used to capture and evaluate the human dynamic properties.Entire body vibration
causes a multi fascinated sharing out of vibration within the body and disagreeable feelings
giving rise to discomfort or exasperation result in impaired performance and health means. This
distribution of vibration is dependent on intra subject variability and inters subject variability.
For this study a multi degree of freedom lumped parameter model has taken for
analysis. The equation of motion is derived and the response function such as seat to head
transmissibility (STHT) driving point mechanical impedance (DPMI) and apparent mass(APMS)
are determined, for this kind of study we can use a neural network (ANN) which is a powerful
data modeling tool that is able to capture and represent complex input/output relationship.
The goal of ANN is to create a model that correctly maps the input to the output using historic
data so that the model can be then used to produce the output when the desired output is
unknown.
Category: General Science and Philosophy
[13] viXra:1601.0333 [pdf] submitted on 2016-01-30 09:09:23
Authors: Mangesh R.Phate1, Mr.Rupesh V. Bhortake
Comments: 17 Pages.
Portable Scheffer reactor (PSR) is an important and useful mechanical device used solar
energy for the numerous applications. The present work consists of 2.7 square meter scheffer
re
ector used for the domestic application in Indian context such as water heating. The
parameters such as the position of the PSR surface with respect to the sun i.e. tilting angle
(AR),the processing timing (TM) measured in 24 Hr clock and the water quantity (WT ) are
considered as a independent parameters. The parameter related with the PSR performance is
the eciency of the PSR (EFF).The response surface methodology (RSM) was used to predict
and analyze the performance of PSR. The experiments conducted based on three factors,
three-level, and central composite face centered design with full replications technique, and
mathematical model was developed. Sensitivity analysis was carried out to identify critical
parameters. The results obtained through response surface methodology were compared with
the actual observed performance parameters. The results show that the RSM is an easy and
effective tool for modelling and analyzing the performance of any mechanical system.
Category: General Science and Philosophy
[12] viXra:1601.0332 [pdf] submitted on 2016-01-30 09:10:29
Authors: Manoj Saini, Navneet Arora, Chandan Pandey, Husain Mehdi
Comments: 8 Pages.
The reactor pressure vessel (RVP) of a pressurized water reactor (PWR) or a boiling water reactor (BWR), i.e., of a light water reactor (LWR), is made of carbon steel. The inside surface is clad with stainless steel to prevent general corrosion. These pressure vessels are expected to with-stand normal and postulated accident conditions. These vessels are installed within a concrete biological shield and the whole plant is in turn surrounded by a concrete containment building. Most of the operating experience relates to two and three loop design. The scope of this paper is to study of mechanical behavior of SA 516 grade 65 carbon steel used for steam generator application undergoing thermal cycling loading. The effect of temperature, cycle time, pre stress and no of cycle would be the varying parameters
Category: General Science and Philosophy
[11] viXra:1601.0331 [pdf] submitted on 2016-01-30 09:11:29
Authors: Husain Mehdi, Anil Kumar, Arshad Mahmood, Manoj Saini
Comments: 11 Pages.
Composite materials are engineering materials made from two or more constituent materials that remain separate and distinct on a macroscopic level while forming a single component. In this work the mechanical properties of GFRP (glass Fiber Reinforcement Plastic), Nylon and their composite with aluminium were evaluated with reference to ASTM D638-02 a. During the tensile load, the maximum strain, and stress are obtained. The maximum strength is found in composite GFRP instead of Aluminium and composite Nylon. Composite material has shown an improvement of mechanical properties when compared with individual materials.
Category: General Science and Philosophy
[10] viXra:1601.0330 [pdf] submitted on 2016-01-30 09:12:48
Authors: Husain Mehdi, Rajan Upadhyay, Rohan Mehra, Adit Singhal
Comments: 11 Pages.
The composite materials consist of two or more different materials that form regions large enough to be regarded as continua and which are usually firmly bonded together at the interface. Many natural and Synthetic materials are of this nature, such as: reinforced rubber, filled polymers, GFRP (Glass Fiber Reinforcement Plastic), Nylon, aligned and chopped fiber composites, polycrystalline aggregates (metals), etc. It is widely used in high speed machinery, aircraft and light weight structures. Crack is a main cause of damage occurring upon dynamic loading and may cause serious failure of structure. The influence of cracks on dynamic characteristics like natural frequencies, modes of vibration of structures has been investigated.
The paper presents the Computational modal analysis of a composite beam with and without cracks. In this work, the mechanical properties of aluminum and fiber (Nylon and Glass fiber reinforcement plastic) are measured a universal testing machine. The three-dimensional finite element models of composite beam with and without cracks are constructed and then computational modal analysis on ANSYS-14 is then performed to generate natural frequencies and mode shapes. The location of cracks will vary from 10 to 90 % of beam length. The finite element model agrees well with the analytical values.
Category: General Science and Philosophy
[9] viXra:1601.0329 [pdf] submitted on 2016-01-30 09:13:45
Authors: Galal A. Hassaan
Comments: 10 Pages.
Compensators are used in place of classical PID controllers for possible achievement of better performance. Unsatisfactory dynamics of some industrial processes represent an engineering problem that hat to be solved. Highly oscillating processes and very slow processes are examples.
In this paper a novel feedback PD compensator based is proposed and applied to control second-order like processes having oscillating characteristics (damping ratio ≤ 0.8). The compensator proposed is capable of controlling the steady-state characteristics of the closed-loop control system and its dynamic characteristics. The advantage of the proposed compensator is its simple structure and tuning using an ITAE objective function. It was possible with the proposed compensator to satisfy a system performance with very low overshoot and settling time. The compensator tuning is reduced to simple relation with the process parameters with correlation coefficient as high as 0.9999.
Category: General Science and Philosophy
[8] viXra:1601.0328 [pdf] submitted on 2016-01-30 09:14:36
Authors: Galal A. Hassaan
Comments: 14 Pages.
Optimal design of shallow foundations used in supporting various machinery is of vital importance. Badly designed foundations result in serious problems such as soil failure, large soil settlement, low vibration efficiency and resonance of structures near by the foundation.
An optimal design approach based on using MATLAB optimization tool box is used to provide the optimal design of a machinery foundation on a silty soil. To minimize the foundation cost the foundation mass is used as an objective function. To control the high technical quality of the foundation from soil mechanics and vibrations point of view, 10 functional constraints are used.
The soil isolation efficiency of the soil is responsible about the vibration transmitted to the surrounding. Therefore, the effect of the minimum isolation efficiency in the range of 71 – 81 % on the foundation optimal design is investigated in details. The performance of the foundation against the minimum isolation efficiency is outlined so that the civil and mechanical engineers can compromise between cost and performance.
Category: General Science and Philosophy
[7] viXra:1601.0327 [pdf] submitted on 2016-01-30 09:15:22
Authors: Galal A. Hassaan
Comments: 9 Pages.
Lag-lead compensators are well known in automatic control engineering. They have 4 parameters to be adjusted (tuned) for proper operation. The frequency response of the control system or the root locus plot are traditionally used to tune the compensator in a lengthy procedure.
A highly oscillating second-order process has a time response to a unit step input of 85.4 % maximum overshoot and about 6 seconds settling time is controlled using a lag-lead compensator (through simulation). The lag-lead compensator is tuned by minimizing the sum of time multiplied by the absolute error (ITAE) of the control system using MATLAB. Three functional constrains are used to control the performance of the lag-lead compensated control system. The result was reducing the process oscillation to 6.926 % overshoot and a 1.413 seconds settling time. The steady-state characteristics of closed-loop control system using the lag-lead compensator were excellent. It is possible reduce the steady-state error to any desired value through one of the compensator parameters.
Category: General Science and Philosophy
[6] viXra:1601.0325 [pdf] submitted on 2016-01-30 09:16:21
Authors: K.Kantha Rao, K. Jayathirtha Rao, B. Sudheer Premkumar
Comments: 16 Pages.
Hypersonic cruise vehicles are fly at Mach numbers of above five (7) and the aerodynamic heating would be severe. Hypersonic Vehicles encounter a severe hazardous environment such as extremely high temperature plane to aerodynamic heating, fluctuating pressures, stresses for which the structures are to be designed and fabricated to withstand these environments to protect various electronic items like guidance, control and instrumentation systems housed in the vehicle structure. High temperature of the order of 15000C and above during the hypersonic flight causes enormous thermal stresses. Inconel-617 is a Nickel based alloy. Hence Inconel-617 is employed as a sandwich material. Theoretical & ANSYS modeling analysis have been done for both, the square and hexagonal honeycomb panels of Inconel-617 material have been performed to suit the hypersonic flight conditions. The honeycomb structures are built from thin walled metal sheets. These structures as a part of the airframe outer cover provide thermal protection to the interior parts mounted inside the vehicle. This paper is to perform geometrical (shape) analysis of different candidate honeycomb cells that have the same effective density but different geometrical shapes. To perform heat-transfer analysis of hypersonic aerospace vehicle structure with different honeycomb cell geometry.
Category: General Science and Philosophy
[5] viXra:1601.0226 [pdf] submitted on 2016-01-21 12:33:26
Authors: Henrique Lara
Comments: 1 Page.
“The gravitational field is space". This idea summarises Einstein's General Theory of Relativity and enables force to be thought of as a curvature, thereby reducing Mechanics to Geometry. The Principle of Equivalence postulated in the present paper enables scales and rulers to be calibrated, just like clocks, whose calibration was achieved thanks to the Theory of Special Relativity through the constancy of the speed of light for all inertial systems. Using the same method, in this paper we deliberate on the meaning of temperature, and put forward a new theory that covers not only rulers, clocks and scales, but also thermometers. To this end, we propose to use the concept of curvature (of space-time) to provide a solution to the problem we seek to solve
Category: General Science and Philosophy
[4] viXra:1601.0225 [pdf] submitted on 2016-01-21 12:35:49
Authors: Henrique Lara
Comments: 1 Page.
The Einstein equation may be understood as a state equation. For this to be possible, entropy must be regarded as being proportional to the area of the causal horizon. However, for this equivalence to make sense, we must seek to define what is meant by temperature and flow of energy in the new context.
Category: General Science and Philosophy
[3] viXra:1601.0147 [pdf] submitted on 2016-01-13 09:52:48
Authors: Sai Venkatesh Balasubramanian
Comments: 3 Pages.
The work purports to discussion of a rarely explored method of answering questions – looking within, where answers might not be “correct” as in the scientific sense, but atleast, they are not answers that promote violence and hatred. The discussions elucidate key points as well as a formulation of asking questions within us and finding the answers.
Category: General Science and Philosophy
[2] viXra:1601.0130 [pdf] submitted on 2016-01-12 13:40:57
Authors: Jeffrey Joseph Wolynski
Comments: 1 Page.
A simple principle of stellar evolution/planet formation is presented in light of the general theory of stellar metamorphosis.
Category: General Science and Philosophy
[1] viXra:1601.0082 [pdf] submitted on 2016-01-09 01:41:44
Authors: Jason Lind
Comments: 3 Pages. The linked papers are just as important of a read as the posted work itself.
This paper convincingly demonstrates the existence of a time-space-thought continuum in metaphysics and theorizes that it indeed exists in the physics.
Largely published in 2012 on www.lind-i.com it has been updated to reflect the author's current interpretations of the subject matter.
Category: General Science and Philosophy