Sound is one of the forms of mechanical energy and the two main characteristics of sound are intensity or power and frequency or wavelength of sound.their performance against the incoming sound wave, industrial silencers can be divided into two general groups of resonating and absorption silencers, the main difference between these silencers is the release of sound energy from the channeling system, which is one of the common examples of the use of resonating type silencers, their use in It is the internal combustion ENGINEs that distinguish absorption silencers from the resonator type based on the fact that the main and visible part of the act of muting the sound is achieved by changing sound energy to heat energy.The goal of this article is to design a muffler based on the breaking of sound frequencies resulting from the movement of fluid in the exhaust output of vehicles, which leads to a reduction of at least 50 db of sound and gives the operator enough peace and concentration. In this article, after examining three types of mufflers, absorbent mufflers that use the properties of porous absorbent material to absorb passing sound and are the simplest form of mufflers, have been selected, analyzed and reviewed and are suitable for the OM457 ENGINE of Idem Industrial Company. It designed for maximum inlet exhaust temperature is 520 and for the maximum kW power is 315 with the maximum discharge relative pressure of 185 mbar for homogenization with the standard atmosphere.

Introduction Flooding is a significant natural hazard that affects millions of people around the world every year and causes extensive damage to property, infrastructure, and ecosystems. Investigating changes in floodplains is very important to understand and reduce these effects. Scientific research reveals that floodplains are affected by various factors, including climate change, urbanization, and river management practices. Notably, recent climate shifts have intensified torrential rains, expanding flood zones and elevating flood risk. Concurrently, urban development and residential expansion contribute to increased flood volume and flow by altering surface runoff patterns and reducing natural water infiltration areas. To optimize flood management strategies, the initial step involves identifying flood-prone regions, creating flood area maps, and monitoring changes over time.  While post-event flood zone mapping and continuous monitoring pose challenges, satellite imagery remains the most practical solution. Advances in earth surface monitoring using satellite technology have significantly enhanced global flood monitoring capabilities. Leveraging satellite imagery and remote sensing technologies, platforms like Google Earth ENGINE provide valuable data for analyzing temporal and spatial variations in flood-prone areas. Materials and methods In the current research, we discuss the continuous monitoring of flood events in relation to the instantaneous maximum flow at the hydrometric station of the Kohak Dam. The Hamuns of Sistan, especially in recent years, have relied solely on water inflow from Afghan rivers during floods. Consequently, we conducted monitoring of the water area of the Hamuns of Sistan during flood events and tracked the water area of the Sistan plain over time using a time series of satellite images spanning from 1984 to 2021. For this purpose, we utilized Landsat satellite images (employing the NDVI index, transition algorithms, and seasonality blue zone identification algorithms) within the Google Earth ENGINE environment. The initial step involved extracting flood dates from the hydrometric station at Kohak Dam, located on the Sistan River at the entrance of the Hirmand River to Iran. Subsequently, we downloaded Landsat satellite images for various dates, including pre-flood, the first image after the flood, and post-water withdrawal (based on the daily hydrograph of the Kohak Dam station). To process and extract information from the images, we performed pre-processing and identified catchment areas of Sistan’s Hamuns during flood events using the NDVI index and infrared and red bands. Additionally, we employed GSWE (Global Surface Water Explorer) algorithms to monitor temporal and spatial water extent distributions globally over the past three decades. Results and Conclusion  Using the dates of flood occurrence at the hydrometric station of Kohak Dam located on the Sistan River (at the entrance of the Hirmand River to Iran), we analyzed three distinct time periods: before the flood, the first date of the satellite image after the occurrence, and after the completion of water withdrawal (based on the daily hydrograph of the Kohak Dam station). During these periods, we downloaded Landsat satellite images.  The obtained results reveal that in the water year 1988-1989, the maximum instantaneous discharge was equal to 901.83 cubic meters per second, occurring on 1989/04/06. Monitoring Landsat satellite images during the three time periods before, during, and after the flood shows that with the arrival of flood flow from the Hirmand River to Iran, the water area of the Hamun wetlands increased. Specifically, after the flooding event, the water area of the Hamun wetlands in Sistan reached 2614.4 square kilometers. In the water years 1990-1991 and 2015-2016, the instantaneous maximum discharge was equal to 1178 and 624.6 cubic meters per second, respectively, occurring on 1991/06/01 and 2016/04/16. The extraction of water areas of Hamun wetlands using the NDVI index from Landsat satellite images shows that in these two flood events, the maximum water area of the Hamun wetlands resulted from flood flow and subsequent inundation. Specifically, the water area was 4477.6 and 1319.8 square kilometers, respectively. Conclusion The study of three maximum annual flood events in the Sistan plain showed that the water intake of Hamun wetlands is completely affected by the occurrence of floods. A step-by-step comparison of the beginning to the end of the flood hydrograph with the flood zones extracted from satellite images in the same time steps, shows the complete matching of the surface of the water zone with the size of the flood discharge. Also, the study of the changes in the water areas of the Hamuns of Sistan using the GSWE layer shows the changes that have occurred in these areas between 1984 and 2020. Therefore, the results obtained from the study of the water zones of Hamuns using GSW maps showed that the water area of Hamuns in the long term shows a sharp decrease, so that the changes occurred in such a way that in the year In 2020, compared to 1984, more than 74% of the area of Sistan's Hamuns is drained seasonally. From the point of view of studying the situation of monthly water intake based on the monitoring of long-term average water areas, the results showed that only a small part of the Sistan plain (about 11 thousand hectares) has water on average throughout the year, and this area also belongs to wells. It is half and covers about 0.5% of the studied area. Also, more than 2 million hectares of the surface of the studied area, on average, have water only in 1 month of the year, which is equivalent to 88.4% of the total area of the studied area (includes Hamuns, the rivers adjacent and the wells).

Land cover map show the spatial distribution of different landscapes such as agricultue, natural resources, water and manmade area. It is a valuable tool to managing and reducing risk in challenging issues such as drought and its effects, food security, flood control, and urban planning. In order to overcome the limitations of field work in the mapping of land cover, the use of satellite images due to the wide, multispectral and update data seems to be suitable. In the study area, the spatially heterogeneous landscapes also makes it difficult to classify features. Therefore, the main purpose of the study is accurate and high resolution land cover mapping using Sentinel-2A images in the Google Earth ENGINE platform. In this regard, three classification algorithms including RF, SVM and CART were evaluated and compared. Various indices were prepared using ratioing and transformation methods. The accuracy of the classifications was evaluated in comparison with ground reference data. Individual bands evaluation showed that the best overall accuracy (49%) was obtained using the CVI index. The best overall accuracy and kappa coefficient of 86% and 0. 82 were obtained by RF algorithm. Therefore, while pointing to the advantages of the GEE including easily accessible data and the ability to process and quickly compare of data, it can be claimed that Sentinel-2A images for land cover mapping in terms of cost, time and accuracy, have high efficiency and the map can be very useful for the management and decision making in different natural and man-made resources for the successful implementation of sustainable development.

Axial vane rotary ENGINE (AVRE), as a novel type of rotary ENGINEs with special and exclusive features, is still under research in some of the reliable ENGINE research centers around the world. The ENGINE is a positive displacement mechanism that permits the four "stroke" action to occur in one revolution of the shaft with a minimum number of moving components in comparison with reciprocating ENGINEs. In this paper, a two-zone combustion model is developed for a spark ignition axial vane rotary ENGINE. Spark ignition ENGINE cycle simulation has been performed on the equivalent four stroke reciprocating ENGINE of the AVRE ENGINE. In this paper, the effect of compression ratio, blowby coefficient, and ENGINE speed on the maximum pressure and temperature of the AVRE are investigated. The modelling is based on equations for energy and mass conservation, equation of state, and mass fraction burned. Combustion chamber is divided into burned and unburned zones, and differential equations are developed for the changes in pressure and changes in temperature in each zone. The developed code for ENGINE simulation in MATLAB is applied to another ENGINE and there has been a good agreement between results of this code and the results related to the ENGINE chosen for validation.

ENGINE downsizing is a trusted method to reduce fuel consumption and pollution emitted from internal combustion ENGINEs. In this method, ENGINE displacement volume is reduced while maintaining the same power/torque characteristics. However, there still exist several limitations to utilize this technology. In this paper, the naturally aspirated type of Iran national ENGINE (EF7-NA) is investigated for a possible downsized version. A one-dimensional ENGINE model equipped with a zero-dimensional two-zone combustion sub-model was developed and validated via experimental results for both natural aspirated and turbocharged ENGINE types. Then experimental and numerical studies were carried out for the primary concept, deactivation of one cylinder besides using a turbocharger. To overcome the concept shortages, especially in lower ranges of ENGINE speed, numerical studies were extended. Deployment of several turbochargers with different performance maps and different valve timing via a dual CVVT system were investigated. The results showed that there is a feasible method for EF7 ENGINE downsizing via a 3-cylinder type equipped with a modified turbocharger and valve timing. The maximum difference between base-ENGINE and downsized version torque is about 7% in low ENGINE speeds.

In order to measure the quality of energy, a concept known as “exergy" is defined. In this study, the exergy of a diesel ENGINE using different blends of diesel and biodiesel fuels (B0, B20, B40 and B100) were investigated. In addition, the effect of speeds of 1200, 1600 and 2000 rpm on analysis of the second law of thermodynamics with various fuels were studied. The parameters evaluated in this study include exergy through work and heat transfer, irreversibility, total exergy, the thermomechanical exergy, and burnt fuel exergy. The results showed that exergy parameters for different blends of diesel and biodiesel fuels increased by the end of combustion stroke and then decreased at the beginning of expansion stroke. Total exergy of B0 increased by 3. 3, 7 and 16. 7% respectively, as compared to B20¡ B40 and B100. The maximum efficiency of the second law of thermodynamics were attained at 2000 rpm as 44. 5, 46. 38, 47. 89 and 48. 5% for B0, B20, B40 and B100, respectively.

This thesis looked at the effect of clay and silt soil blocking the heat transfer area of the radiator and its effect on the ENGINE coolant through the conduct of experiments and a mathematical model developed. The results indicated that the percentage area covered resulted in a proportional increase of the inlet and outlet temperatures of the coolant in the radiator. The mathematically model developed also predicted the experimental data very well. Regression analysis pointed out that every 10% increase area of the radiator covered with silt soil resulted in an increase of about 17 oC of the outlet temperature of the radiator coolant.Similarly, using clay as a cover material, 10% of the area covered of the radiator resulted in an increase of about 20 oC of the outlet temperature of the radiator coolant. Statistical analysis pointed to the fact that the result obtained for clay, silt and the mathematical model were not significantly different. Thus, irrespective of the type of material that blocks the radiator surface area, the coolant rises with proportion of the radiator covered.