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In the current study, the relation between the psychrometry working upon the thermodynamic analysis of humid air and drying at a timber dryer was investigated. In order to bring the air to suitable drying conditions, an air conditioner unit was used and the mass change of the unit with energy was analyzed. In the psychrometric analysis of the timber dryer with a heat pump, the pine and poplar timber were used. The mass change in the timber was followed with a load cell. At the end of the analysis, the amounts of humidity vaporized and intensified at the timber after drying were compared. Depending on these values, 5.7 kg humidity was taken from the pine timber at the end of 50 h, and 12.5 kg from the poplar timber at the end of 70 h.

In this study, the effects of ethanol additives (5%, 10% and 15% in volume) on the performance and emissions (HCs, CO, CO2 and NOx) of a SI two stroke engine is investigated in different loads and speeds. Also, the effect of exhaust temperature and delivery ratio on emissions and engine performance is discussed. Results show that in most test cases, when alcoholic fuel is used, scavenging efficiency and delivery ratio increased due to rapid evaporation of ethanol and outcomes of scavenging and trapping efficiencies are in more accordance with the perfect mixing model. The most outstanding result of using ethanol additives is significant reduction in pollutions emitted from engine of which CO with 35% reduction has the most reduction percentage among other pollutants. Although most emissions are increased by increasing the exhaust temperature, but hydrocarbons (HCs) on an average decreased by 30% on increasing the exhaust temperature.

Several studies have shown that fractal geometry is a tool that can replicate and investigate the nature of the materials and their physical properties. The Sierpinski carpet is often utilized to simulate porous microstructures. By using this geometric figure it is possible to study the influence of pore size distribution on deterministic fractal porous media. The determination of the thermal conductivity can be carried out using the electrical analogy. So, microstructure models have been converted in electrical fractal patterns. This fractal procedure is characterized by a close relationship with the actual microstructure and prevent papers has been validate it with experimental data in a series of former papers. In this work it is possible to show how thermal conductivity changes in relation to pore size distribution and geometric microstructure parameters.

The requirement for the temperature stability is very high in the star sensors as the high precision needs for the altitude information. Thermal design and analysis thus is important for the high power star sensors and their supporters. CCD, normally with Peltier thermoelectric cooler (PTC), is the most important sensor component in the star sensors, which is also the main heat source in the star sensors suite. The major objective for the thermal design in this paper is to design a radiator to optimize the heat diffusion for CCD and PTC. The structural configuration of star sensors, the heat sources and orbit parameters were firstly introduced in this paper. The influences of the geometrical parameters and coating material characteristics of radiators on the heat diffusion were investigated by heat flux analysis. Carbon–carbon composites were then chosen to improve the thermal conductivity for the sensor supporters by studying the heat transfer path. The design is validated by simulation analysis and experiments on orbit. The satellite data show that the temperatures of three star sensors are from 17.8 °C to 19.6 °C, while the simulation results are from 18.1 °C to 20.1 °C. The temperatures of radiator are from 16.1 °C to 16.8 °C and the corresponding simulation results are from 16.0 °C to 16.5 °C. The temperature variety of each star sensor is less than 2 °C, which satisfies the design objectives.

This paper presents the results of numerical study of turbulent flow and heat transfer in a channel with inclined detached-ribs. The computations based on the finite volume method, and the SIMPLE algorithm have been implemented. The study encompasses the Reynolds number (based on the hydraulic diameter of a channel) range from 4000 to 24,000. The heat transfer, pressure loss and thermal performance of the inclined detached-ribs with different attack angles ( θ ) of 0°, 15°, 30°, 45°, 60°, 75°, 105°, 120°, 135°, 150° and 165° are examined and compared with those of the typical transverse attached rib with θ of 90 o . The computational results reveal that, at high Reynolds number, the inclined ribs with θ =60 o and 120 o yield comparable heat transfer rates and thermal performance factors which are higher than those given by the ones with other angles. On the other hand, at low Reynolds number, the effect of rib attack angle is insignificant.

Nanofluids are a new generation of high-efficiency refrigerant with abnormal increased thermal conductivity and convective heat transfer properties. In view of the paucity of research work on the contribution of nanoparticle Brownian motion for the thermal conductivity augmentation, the present paper carries out a series of MD simulations to explorer the order of magnitude of nanoparticle Brownian motion and discusses the effect of nanoparticle Brownian motion for thermal conductivity enhancement of nanofluids. Various influence factors including nanoparticle shapes, sizes, and materials are considered. The Brownian motion of nanoparticles is decomposed into rotation and migration and calculated by MD simulation. By means of Peclet number, the effect of nanoparticle Brownian motion for thermal conductivity enhancement of nanofluids is discussed.

The thermal power plants are used to generate power. The thermal power plants are designed based on required conditions, but actually inlet conditions are not as per the designed conditions. Variations in the power outputs from power plant are always a matter of disputes. So correction curves for power and heat rate are generated. In this paper, the thermodynamic analysis of 120 MW thermal power plant has been done at particular inlet pressure (124.61 bar) and at different inlet temperatures (507.78 °C, 517.78 °C, 527.78 °C, 537.78 °C, 547.78 °C, 557.78 °C, and 567.78 °C). The correction curves for power and heat rate have been generated for combined effect of inlet pressure and different inlet temperatures. These curves indicate that if inlet pressure is 124.61 bar and inlet temperatures vary, then power output and heat rate also vary.

During the process of cooling system design, the traditional method is calculating power losses of power devices, building thermal model of power devices, establishing system structure model, and making thermal analysis. While, the ideal assumptions and complex equivalent models in traditional methods bring in large error and the analysis of whole system model reduces the effectiveness of cooling system design for complicated high-power inverters. In this paper, the power losses of power devices in NPC ( Neutral - Point - Clamped ) three-level inverter based on SVPWM(Space Vector Pulse Width Modulation) was calculated firstly; the input power and cooling power of each power module block were analyzed, and the cooling power of each block supplied by cooling fan was obtained to figure out the cooling fan parameters. The designed forced-air cooling system was proved by finite element simulation. Finally, the temperature rise experiment was carried out on a 1 MW NPC three-level inverter, and the results proved the effectiveness and feasibility of the proposed method.

In this paper, the potential and the cost-effectiveness of a solar photovoltaic power plant for meeting the energy demand of garment zone at Jaipur (India) is analyzed. Also, the energy demand of garment zone for year 2011has been estimated (2.21 MW) and the design of the solar PV power plant of 2.5 MW capacity has been proposed, which requires about 13.14 acres of land area. Looking at the scarcity and cost of the land near the city, an off-site proposal for the power plant has also been considered and compared with the on-site option. For the on-site solar PV power plant internal rate of return (IRR) is 11.88%, NPV @ 10% discount rate is 119.52 million INR, simple payback period is 7.73 years and discounted payback period @10% is 15.53 years, while for the off-site power plant IRR is 15.10%, NPV is 249.78 million INR, simple payback period is 6.29 years and discounted payback period is 10.14 years. Levelized cost of energy is Rs. 14.94 and Rs. 11.40 per kW h for on-site and off-site solar PV plants respectively @ 10% discount rate, which is quite attractive.

This paper presents an efficient technique of linearization of the nonlinear convective terms present in engineering problems involving heat and mass transfer and fluid mechanics. From two numerical applications, this technique with a method of high-order finite differences is validated by numerical solution of transient nonlinear diffusive–convective problem in three dimensions.

In this paper, turbulent forced convection of nanofluids flow in triangular-corrugated channels is numerically investigated over Reynolds number ranges of 1000–5000. Four different types of nanofluids which are Al 2 O 3 , CuO, SiO 2 and ZnO–water with nanoparticles diameters in the range of 30–70 nm and the range of nanoparticles volume fraction from 0% to 4% have been considered. The governing equations of mass, momentum and energy are solved using finite volume method (FVM). The low Reynolds number k – e model of Launder and Sharma is adopted as well. It is found that the average Nusselt number, pressure drop, heat transfer enhancement, thermal–hydraulic performance increase with increasing in the volume fraction of nanoparticles and with decreasing in the diameter of nanoparticles. Furthermore, the SiO 2 –water nanofluid provides the highest thermal–hydraulic performance among other types of nanofluids followed by Al 2 O 3 , ZnO and CuO–water nanofluids. Moreover, the pure water has the lowest heat transfer enhancement as well as thermal–hydraulic performance.

In this study, the coupled thermomagnetic system of a switched reluctance motor for cooling performance improvement has been conducted numerically. The switched reluctance motor (SRM) with output power of 3 kW and air cooling is under investigation. Aluminum cooling fins are fitted on the cooling casing of the motor in order to increase the convection surfaces. The commercial softwares used in this paper are JMAG-Designer and CFD-RC for electromagnetic field and thermal field analyzes, respectively. The electro-magnetic analysis for the switched reluctance motor is obtained in advanced in order to obtain the energy losses. They can then be treated as the heat sources for heat transfer analysis. Transient solutions for the temperatures of the components in SRM are calculated during operation. The transient temperature of SRM is analyzed for both with and without cooling casing. The influence of forced convection by the internal fan of the SRM is also under investigation. Results show the numerical model is in good agreement to the real practice. The model can be used for the SRM cooling design.

The energy requirement pattern of world is growing up and developing technology. The available sources, while exhausting and not friendly to the environment, are highly used. Looking at partial supply and different options of environment problems associated with usage, renewable energy sources are getting attention. MSW (Municipal solid waste) composition data had been collected from 1997 to 2009, in Benghazi Libya, to evaluate the waste enthalpy. An incinerator with capacity of 47,250 kg/h was confirmed to burn all the quantity of waste generated by the city through the next 15 years. Initial study was performed to investigate energy flow and resource availability to insure sustainable MSW required by the incinerator to work at its maximum capacity during the designated period. The primary purpose of the paper is to discuss the design of Rankin steam cycle for the generation of both power (PG) and combined heat power (CHP). In the power generation case, the system was found to be able to generate electrical power of 13.1 MW. Including the combined heat power case, the results showed that the system was able to produce 6.8 million m 3 / year of desalinated water and generate 11.33 MW of electricity. In conclusion, the CHP designed system has the greatest potential to maximize energy saving, due to the optimal combination of heat production and electricity generation.

Higher efficiency, lower energy consumption and less pollution are become more and more important in chemical engineering. Post-process is one of the key parts for producing chemical productions. Thus, we develop a novel device, Chemical Post-Processing Integrated Equipment (CPPIE), which can deal with crystallization, filtration, washing and drying in the same tank by changing the position of it. Without the transfer during these processes, CPPIE have meaningful advantages compared to conventional devices. In this paper, the structure and the working procedure of CPPIE are introduced, and Diaphragm press drying device (DPDD) in CPPIE is further described. Then, the experimental setup is arranged. Its drying and energy consumption performances are experimentally investigated. The performance of DPDD is analyzed experimentally with theory to validate it can meet the requirements of industrial applications. Furthermore, the energy consumption for the whole processes is calculated with experimental data. Compared to CPPIE without DPDD, CPPIE with DPDD has energy conservation about 25%. This work presents the feasibility of CPPIE, the advantage of DPDD for drying process with lower energy consumption, which can be referenced for designing similar integrated equipment.

In this research paper the energy, exergy and power generation of building integrated semitransparent photovoltaic (BISPV) modules for roof and facade has been evaluated. Solar radiation intensity on BISPV modules surfaces is an essential parameter for assessing energy and exergy. The experimental setup consists of two BISPV modules, each of 75W rating, which has been conducted on a clear sky day at roof and facade of Energy Centre building, MANIT Bhopal, India. It is observed that the energy efficiency varies between 11-18% at roof and 13-18% at facade throughout the day. The maximum value of electrical efficiency of BISPV module is 85% at roof and 72% at facade.

In this study, performance of a 50 kW organic Rankine cycle (ORC) with internal heat exchanger (IHE) having R245fa/R152a zeotropic refrigerant with various compositions was investigated. The IHE could reduce heat rate at the ORC evaporator and better cycle efficiency could be obtained. The zeotropic mixture could reduce the irreversibilities during the heat exchanges at the ORC evaporator and the ORC condenser due to its gliding temperature; thus the cycle working temperatures came closer to the temperatures of the heat source and the heat sink. In this paper, effects of evaporating temperature, mass fraction of R152a and effectiveness of internal heat exchanger on the ORC performances for the first law and the second law of thermodynamics were considered. The simulated results showed that reduction of R245fa composition could reduce the irreversibilities at the evaporator and the condenser. The suitable composition of R245fa was around 80% mass fraction and below this the irreversibilities were nearly steady. Higher evaporating temperature and higher internal heat exchanger effectiveness also increased the first law and second law efficiencies. A set of correlations to estimate the first and the second law efficiencies with the mass fraction of R245fa, the internal heat exchanger effectiveness and the evaporating temperature were also developed.

This paper presents the results of an experimental study that was conducted in 15 office buildings in the humid and cold tropics during the working hours of the dry and rainy seasons in Cameroon. This was with the aim to study the effects that local and imported materials had on indoor air quality. To achieve this objective, the adaptive model approach has been selected. In accordance with the conditions of this model, all workers were kept in natural ventilation and, in accordance with the general procedure, a questionnaire was distributed to them, while variables, like air temperature, wind speed, and relative humidity were sampled. The results showed a clear agreement between expected behaviour, in accordance with the characteristics of building construction, and its real indoor ambience once they were statistically analysed. On the other hand, old buildings showed a higher percentage of relative humidity and a lower degree of indoor air temperature. Despite this, local thermal comfort indices and questionnaires showed adequate indoor ambience in each group of buildings, except when marble was used for external tiling. The effect of marble as an external coating helps to improve indoor ambience during the dry season. This is due to more indoor air and relative humidity being accumulated. At the same time, these ambiences are degraded when relative humidity is higher. Finally, these results should be taken cognisance of by architects and building designers in order to improve indoor environment, and overcome thermal discomfort in the Saharan area.

This paper deals with the steady state thermal analysis of diesel engine piston coated with ceramic coating having holes on its surface. Temperature distribution on the piston's top surface and substrate surface is investigated by using finite element based software called Ansys. Yttria-stabilized Zirconia is used as ceramic coating applied on Al–Si piston crown. The 2 thickness of ceramic top coating is about 0.4 mm and for NiCrAl bond coat it is taken to be 0.1 mm. Temperature distribution is investigated by choosing various radiuses of holes created on the ceramic coating surface about 1.5 mm, 2 mm and 2.5 mm. From the results it is observed that the top surface (coated surface) temperature is increasing with increase the radius of the holes. Maximum temperature of coated surface is occurs for highest hole radius of about 2.5 mm. Compared with coating have no hole, a significant increase in the pistons top surface temperature occurs with coating having holes. Although, the substrate temperature is decreasing with increase the radius of the holes.

This paper investigates usage of thermal energy storage extracted from concentrating solar heater for water distillation. Paraffin wax selected as a suitable phase change material, and it was used for storing thermal energy in two different insulated treasurers. The paraffin wax is receiving hot water from concentrating solar dish. This solar energy stored in PCM as latent heat energy. Solar energy stored in a day time with a large quantity, and some heat retrieved for later use. Water’s temperature measured in a definite interval of time. Four cases were studied: using water as storage material with and without solar tracker. Also, PCM was as thermal storage material with and without solar tracker.The system working time was increased to about 5 h with sun tracker by concentrating dish and adding PCM to the system. The system concentrating efficiency, heating efficiency, and system productivity, has increased by about 64.07%, 112.87%, and 307.54%, respectively. The system working time increased to 3 h when PCM added without sun tracker. Also, the system concentrating efficiency increased by about 50.47%, and the system heating efficiency increased by about 41.63%. Moreover, the system productivity increased by about 180%.