Induction Heating is widely used in metal industry for melting or Heating thin slabs in a continuous casting plant. The wide application is based on good efficiency, high production rate and non-polluting conditions. For designing a Parallel resonant induction Heating system, calculating the capacitance for the resonant circuit is important, because its value affects resonance frequency, output power, power quality factor, Heating efficiency and power factor.In this paper, phase controlled rectifier and H-bridge inverter are modeled. Then a method of finding an optimal value for the capacitance under voltage constraint is presented. This value is selected for maximizing output power of an induction heater, while minimizing the power loss of capacitor at the same time. For this purpose, the role of equivalent series resistance in the choice of capacitance value is significantly recognized. In this regard, the Heating coil and the load of induction Heating are modeled at first, and then the optimal value of capacitance is selected. Finally a complete model of heater and its power is simulated and effectiveness of the proposed method is verified.

The aim of this research is an analytical investigation of heat and mass transfer for the MHD nanofluid flow passed between non-Parallel stretchable/shrinkable walls. In order to model nanofluid flow, effects of Thermophoresis, Brownian diffusion, and Joule Heating are considered. The governing mass, momentum, and energy equations are solved analytically by applying Duan-Rach method, which caused to get a solution for the undetermined coefficients from conjectured profiles of variables without using numerical methods. Comparison between the current results with the numerical results of other references shows good agreement. The effects of the Reynolds number, opening angle parameter, and the Hartman number on the temperature, velocity, and concentration profiles have been investigated in the case of both convergent and divergent plates, either stretched or shrunk. Also, the effects of the Thermophoretic and Brownian parameters on the Nusselt number are obtained. This study indicates that increasing the Hartman number decreases the concentration profile and increasing in the temperature profile for divergent channels. In this case, as the opening angle parameter rises, the thickness of the thermal boundary layer increases. Also, for convergent and divergent channels, the increase in the thermophoretic parameter causes increases the Nusselt number. By applying an identical magnetic field to two divergent stretching and shrinking channels, the concentration profile in the stretching channel is more than the shrinking one. For convergent channels, this treatment of concentration profile is completely vice versa.

A B S T R A C T Temperature is one of the climate elements that has fluctuated a lot over time. When these fluctuations increase and decrease more than normal and are placed in the upper and lower regions of the statistical distribution, if continued, it can lead to the creation of Heating and cooling waves. The purpose of this study is to analyze the temporal and spatial changes in Heating and cooling waves in Iran during a period of 50 years. For this purpose, the temperature of 663 synoptic stations from 1962 to 2004 was obtained from the Esfazari database. Then, in order to complete this database, the daily temperature from 2004 to 2011 was obtained from the Meteorological Organization of the country and added to the aforementioned database. In order to perform calculations and draw maps, Matlab, grads and Surfer software have been used. The results of this study showed that the index of cooling waves and Heating waves, while having a direct effect on each other, had an increasing trend in most of the area of Iran. The statistical distribution of the index of cooling waves is more heterogeneous than that of the index of Heating waves. So that the spatial variation coefficient for cold waves is 84.22%. Also, the index of cooling waves has more spatial variability. The highest common diffraction of the index of Heating and cooling waves has been seen in the northwest, east and along the Zagros mountains. Analysis of the indexes trends show that heat waves have intensified in 65.8% of Iran and the intensity of cold waves has decreased in 48.5% of Iran Extended Abstract Introduction Temperature is one of the major climatic variables, which it has a direct impact on different aspects of human life. It plays an essential role in the growth of crops and is considered a key driver of the biological system(Reicosky et al, 1988). It is associated with several types of extremes, for example, heat and cold waves which caused human societies maximum damage. Past occurrences of heat waves hitherto had significant impacts on several aspects of society. Have increased Mortality and morbidity. Ecosystems can be affected, as well as increased pressure on infrastructures that support society, such as water, transportation, and energy(Dewce, 2016). The long-term change of extreme temperatures has a key role in climatic change. The form of statistical distribution and the variability of mean values and also extreme event indicate a change in the region. It can be a small relative change in the mean as a result of a large change in the probability of extreme occurrence. Also, the variation in temperature data variance is significantly more important than the mean, for assessing the extreme occurrence of climate(Toreti and Desiato, 2008). The average surface temperature has increased the world between 0.56 and 0.92 ° C over the past 100 years(IPCC, 2007). Meanwhile, it was in the Middle East, the average daily temperature increased by 0.4-0.5 ° C in decades(Kostopoulou et al, 2014; Tanarhte et al, 2012). Considering that not many studies have been done in the field of spatio-temporal Variations of the Heating and cooling waves thresholds in Iran, in this study, the spatio-temporal Variations of the Heating and cooling waves thresholds in Iran during 50 years were examined and analyzed.   Methodology The daily temperature from the beginning of the year 21/03/1967 to 19/05/2005 was obtained from the Esfazari database prepared by Dr. Masoudian at the University of Isfahan. In order to increase the time resolution of the mentioned database, the daily temperature of observations from 05/21/2005 to 05/12/2012 has been added to the mentioned database using the same method, and the exact spatial resolution (15 x 15 km) is used as a database. Threshold indices of Heating waves are the average numbers between the 95th and 99th percentiles, that is, the extreme hot threshold to the limit of excessively extreme hot. For extreme cool, from the 5th percentile down to zero is used. Of course, a condition was added to these thresholds, which is that these thresholds must be repeated two days in a row. These thresholds were extracted for each day in the 50 years of the study period and used as the original database. In order to analyze the relationship between cooling and Heating waves, Pearson's correlation coefficient was used and regression was used to analyze the trend.   Results and discussion The average of cold waves was 5.26 ° C and for the heat waves is 30.20° C. Generally, if the temperature is upper or lower than this threshold, it is considered as hot or cold temperatures. A comparison of the median, mode, and average of cold waves with heat waves shows that the distribution is more heterogeneous for cold waves and its CV is 84.22%. In southern Iran, the average threshold heat waves are higher. This situation can be caused by the effects of subtropical high-pressure radiation, low latitude, and proximity to the sea. Though the threshold is higher in these areas, fewer fluctuations and changes are seen in the area. Heights moderate the temperature so they pose a minimum threshold for heat waves i.e. an iso-threshold of 25 ° C is consistent along the Zagros mountain chains, but in the west and east of Zagros Mountains, the threshold of heat waves is increased. Heat waves have increased in most areas of the country. So nearly 85 percent of the Iran has been an increasing trend, of which 65.8 percent is statistically significant at the 95% confidence level. Still, more areas of the country (60 percent) have a trend between 0.00828 and 0.00161. As can be seen, only 15% of the land area (including the southwest and northwest of the Country) had decreased heat waves. Cold waves, in most parts of the country, have a Positive Trend. However, about 25 percent of the study area's cold waves have a negative trend. they are located in areas higher than Latitude 30°. The largest decline of the wave's trend along the country is highlands. Nowadays, most of the country, has a trend between 0.01494 and 0.00828 ° C, respectively. Conclusion Common changes and effects of heat and cold waves had a direct relationship in many parts of the country. It is remarkable common variance in the East reached 55 percent, according to statistical significance. In some areas of the northwest and southwest, which have been impressive heights, the common variance is 40 percent. This common variance in mountains area has been high values. Investigation of heat waves trend shows that 65.8% of Iran significant positive trend and 7.1% significant negative trend. Also, the cold waves trend has indicated a 48.5% significant positive trend and a 10.8% significant negative trend. Climate change and global warming have changed the frequency and severity of temperature extremes. The present study, by examining the number of warm waves, concluded that the warm waves have increased in magnitude in 65.8% of the Iran zone. Also, the study of the cold waves trend showed that 48.5 percent of Iran had a positive trend, which means that the amount of temperature in the cold waves increased In other words, the severity of the cold has been reduced And only 10.8 percent of Iran had a negative cold wave trend And it shows the intensity of these waves is reduced.   Funding There is no funding support.   Authors’ Contribution The authors contributed equally to the conceptualization and writing of the article. All of the authors approthe contenttent of the manuscript and agreed on all aspects of the work declaration of competing interest none.   Conflict of Interest The authors declared no conflict of interest.   Acknowledgments  We are grateful to all the scientific consultants of this paper.

Residual stress is one of the most substantial defects of welded parts caused by intensive thermal gradient. In this study, different mechanical and thermal techniques for reducing residual stresses have been investigated and the effectiveness of contributing parameters has been discussed afterwards. Subsequently, some equations have been proposed for welding energy and exergy efficiency and the effects of Parallel flame Heating, vibration method, and hammer working method on reducing welding residual stresses are expressed. The results show that by using Parallel Heating technique, the enhancement of flame power would result in reducing both energy and exergy efficiencies. However, the decremental rate of the two efficiencies would slow down and they approach to an asymptotic value. Increasing the speed of welding improves two efficiencies more than 2 times. On the other hand, the normalized entropy is reduced by increasing the heat input of the flames. This fact is an indicator of a reduction in welding residual stress. This reduction is more at high speeds. Eventually, the ratio of the two efficiencies shows that in this study, economical power was about 1800j/s. The reduction of normalized entropy for the vibration, hammering, and Parallel flame methods are 0. 001, 0. 1, and 10, respectively. Overall, it is expected that thermal methods are more efficient than mechanical methods in reducing residual stresses.

The purpuse of this essay is that scrutiny semblance of ancient myths of iran and comparison of those. The author mentions his theory about to how start of myths then he conclude the relation between myth and philosophy. In continue he scrutiny of most important similes between persian myths and adventures of prophets and unmerciful kings which mention in holy books. For example similes between siavoosh and abraham.The most important conclude of these essay is reletions between myths and historical adventures or between two diffrent myths and how efficacy of those.

Magnetically confined plasma can be heated with high power microwave sources. In spherical torus the electron plasma frequency exeeds the electron cyclotron frequency (EC) and, as a consequence, electromagnetic waves at fundamental and low harmonic EC cannot propagate within the plasma. In contrast, electron Bernstein waves (EBWs) readily propagate in spherical torus plasma and are absorbed strongly at the electron cyclotron resonances. In order to propagate EBWs beyond the upper hybrid resonance (UHR), that surrounds the plasma, the EBWs must convert via one of two processes to either ordinary (O-mode) or extraordinary (X-mode) electromagnetic waves. O-mode and X-mode electromagnetic waves lunched at the plasma edge can convert to the electron Bernstein waves (EBWs) which can propagate without and cut-off into the core of the plasma and damp on electrons. Since the electron Bernstein wave (EBW) has no cut-off limits, it is well suited to heat over-dense plasma by resonant absorption. An important problem is to calculate mode conversion coefficient that is very sensitive to density. Mode conversion coefficient depends on Budden parameter (h) and density scale length (Ln) in upper hybrid resonance (UHR). In Mega Ampere Spherical Tokamak (MAST), the optimized conversion efficiency approached 72.5% when Ln was 4.94 cm and the magnetic field was 0.475 Tesla in the core of the plasma.

The heat and mass transfer of a magnetohydrodynamic micropolar Carreau nanofluid on a stretching sheet has been analyzed. An internal Heating, thermal radiation and viscous dissipation effects are also incorporated. The system of the governing partial differential equations is converted into the ordinary differential equations by invoking the similarity transformation. The resulting ordinary differential equations are then solved by the well known shooting technique. The impact of pertinent physical parameters on the velocity, angular velocity, temperature and concentration profiles are analyzed graphically. The dimensionless velocity is enhanced for the Weissenberg number and the power law index while reverse situation is studied in the thermal and the concentration profile.

Waste materials are being generated around the world every year. Some of these are effectively collected and recovered for use as an energy source or chemical feedstock, while others are simply discarded or burned which in many ways polluting the environment. The improper disposal of these waste materials may constitute an environmental hazard due to the presence of undesirable species such as metals, soot and polycyclic aromatic hydrocarbons. New technologies are being investigated to develop systems which shall support the safe handling, transportation, storage, disposal and destruction of the hazardous constituents of these wastes. The recent interest in microwave technologies due to the extent of the treatments and assisted applications promoting a specific technology has been highlighted against conventional methods, and appears to offer the best alternative to waste management. This paper discusses the potential use of microwave as an energy-efficient mean to current Heating technologies employed in the processing and treatment of wastes. The process applications considered are the treatment and control of specific and often problematic waste-streams including; electrical and plastic as well as; industrial and municipal sludge and automotive industry wastes. Moreover, it presents an extensive review of the scientific literature associated with various microwave pyrolysis applications in waste to energy engineering.