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In the recent years, a lot of research has been carried out in the field of nanofluid based solar collector, leading towards the enhancement of working efficiency even at low atmospheric temperature or at low sunlight levels regions of the world. The present review pertains to the research progress related to the performance execution of solar collector using nanofluid. It is observed that the thermal energy storage system (TES), using solar collector, is a useful device for storing sensible and latent heat in a unit volume. Nanofluid plays an important role in various thermal applications such as heat exchanger, solar power generation, automotive industries, electronic cooling system, etc. The nanoparticles find the use in various industrial applications because of its properties, such as thermal, mechanical, optical and electrical. Most of the investigations carried out earlier on the applications of nanofluid in solar energy are related to their uses in the solar collector and thermal storage system. The parabolic solar collector using nanofluid is still a challenge. This article presents an exhaustive review of thermal storage system using nanofluid based solar collector and a scope of using nanofluid based solar collector for performance enhancement.

Purpose This paper aims to present an experimental investigation and optimization of a low-temperature thermoelectric module to examine the influence of the main operating conditions. Design/methodology/approach In this work, a comparison was made by varying the various operating parameters such as heat source temperature, the flow rate of the cold fluid and the external load resistance. A Taguchi method was applied to optimize the parameters of the system. Three factors, including the external load resistance, mass flow rate of water (at the heat sink side) and heater temperature (at the heat source side) along with different levels were taken into account. Analysis of variance was used to determine the significance and percentage contribution of each parameter. Findings The experimental results show that the maximum power output 8.22W and the maximum conversion efficiency 1.11 per cent were obtained at the heater temperature of 240°C, the cold fluid mass flow rate of 0.017 kg/s, module temperature difference of 45°C and the load resistance of 5 O. It was observed that the optimum parameter levels for maximum power output determined as 5 O external load resistance, 0.17 kg/s mass flow rate of water and 240°C heater temperature (A1B3C3). It reflects that these parameters influence on the optimum conditions. The heater temperature is the most significant parameter on the power output of the thermoelectric module. Originality/value It is clear from the confirmation test that experimental values and the predicted values are in good agreement.

Around 60–70% of the fuel energy in an internal combustion engine is lost as waste heat through engine exhaust and coolant. Hence, waste heat recovery techniques can be used to increase the efficiency of the engine. Thermoelectric systems are widely used for converting heat energy to electric energy. A considerable attention of researchers has been drawn by the thermoelectric generator, for the waste heat recovery from engine exhaust. The thermoelectric generator is one of the promising green energy source and the most desirable option to recover useful energy from engine exhaust. A high-efficiency heat exchanger, which is an integral part of the thermoelectric generator, is necessary to increase the amount of heat energy extracted from engine exhaust at the cost of acceptable pressure drop. The present work is a summary of thermoelectric materials, and heat exchanger studies on heat transfer rate, thermal uniformity, and pressure drop. The heat exchangers with different internal structures enhance heat transfer rate and thermal uniformity, which increase the power output and the conversion efficiency of the thermoelectric generator. The presence of flow-impeding inserts/internal structures results in an adverse increase in pressure drop and has a negative effect on the performance of waste heat source.

In this work more emphasis was given on the comparison of regeneration performance of silica gel and composite desiccant wheels by parabolic trough solar collector (PTSC). The composite desiccant wheels include silica gel-molecular sieves (90% silica gel + 10% molecular sieves), silica gel-lithium chloride (90% silica gel + 10% lithium chloride) and silica gel-lithium chloride-molecular sieves (80% silica gel + 10% lithium chloride + 10% molecular sieves). The performance was checked at different air flow rates with different regeneration to process ratio in parallel and counter flow arrangement. From experimental evaluation it was observed that composite desiccant wheel made from silica gel-lithium chloride- molecular sieves has enabled more regeneration rate and regeneration effectiveness for varying regeneration temperature and ambient relative humidity ranging from 52.3-71.3°C and 55-73% respectively. The percentage improvement in regeneration rate was 5.014%, 6.290% and 12.807% for composite desiccant wheel made from silica gel-molecular sieve, silica gel-lithium chloride and silica gel-lithium chloride-molecular sieves respectively.

The heat transfer characteristics of current fluids are tremendously improved by suspending nano-sized solid particles with diameter below 100 nm and are considered as prospective working fluids for the applications such as solar collectors, heat pipes, nuclear reactors, electronic cooling systems, automobile radiators etc. The present paper summarizes the current research in the nanofluid studies on convective heat transfer performance, thermo-physical properties, effect of fluid temperature, inlet velocity, use of surfactant for better stability of nanofluids, particle size, and volume concentration effects. The article also suggests the direction for future developments.

Salinity gradient solar pond is an integral thermal energy collection and storage device. Energy extracted from the storage zone can be utilized for power generation, process heating, drying agriculture products, and desalination. In case of buried solar pond, the thermal performance of the pond is highly dependent on the ground conditions. A numerical model was used to investigate the effect of depth of ground water table and thermal conductivity of the soil on the storage zone temperature. The model used has a good agreement with the experimental data. It was found that storage zone temperature and warm-up period is highly influence by the ground conditions.

In the twenty-first century, composites of domestic polymer material with natural fibers are gaining considerable importance due to numerous valid reasons such as environmental protection, balancing ecosystem besides consumer demands, and allied legislation issues. Thus, the quest of manufacturing industries for generating new material is boosted tremendously. Blends and composites of polypropylene have been popularly used since about last thirty to forty years to manufacture completely innovative novel materials. These materials have combined entity characteristics of the basic module polymers. The success of these synthesized blends and composites is entirely dependent on compatibilization of the parent polymers with the additives. Improvisation in the blend morphology, enhancement in contact area adhesion, and furthermore consequently improvement in the concert service of blend are the basic outcomes of the compatibilization. Blends of polypropylene (PP) with synthetic and natural fibers are gaining special importance because they allow increment in the thermal and mechanical properties of the new material that combined with the process ability of the PP. The new material developed is definitely a cost-effective and largely being used in automotive sector besides its uses in various other industrial sectors. The mechanical properties (flexural strength, impact strength, stiffness, higher strength-to-weight ratio, and modulus) and thermal properties like heat deflection temperature are having great importance in case of polypropylene.

The energy demand in the world is increasing day by day, and fossil fuel shortages are also increasing. Solar energy and renewable energy resources become more important. Most of the Indian population is lives in rural area and use wood for the cooking purpose. The thermal energy storage is popular in this era for the cooking purpose. Thermal energy storage system based on solar collector is developed for the cooking of bread in mind. The oil- and aluminum-based energy storage system is used for experimentation and having same storage potential and to store the energy in storage contain phase change material which have melting temperature of 210–220 °C. Energy collected by solar collector heated the fluid (i.e., soybean oil) contained in receiver tube and carry the energy to storage space. The self-circulation unit is introducing between storage and solar collector which contain soybean oil as a heat transfer fluid. Main aim of the concept is to store energy during day and utilized it in nighttime for cooking purpose.

Charging of energy storage system using flat plate solar collector (FPSC) is very popular in recent years. FPSC for the thermal energy storage system (TESS) using hybrid nanofluid was discussed in this manuscript. Hybrid nanofluid of CuO+ Al2O3/water was used as heat transfer fluid (HTF) for solar collector which is coupled with thermal storage and analysis carried out. To predict the thermal performance of energy storage system using hybrid nanofluid, a stainless steel container was used for thermal storage. CuO+Al2O3/water hybrid nanofluid were used to investigate the thermal performance of the solar collector and energy storage system. The FPSC is used for experimental investigation on the stainless steel container TESS. The flat plate solar collector is found more efficient than the other conventional type solar collector using hybrid nanofluid. The temperature of stainless steel container thermal energy storage system was reached to 87°C by using hybrid nanofluid in FPSC.

Desiccant dehumidification system is an alternate option against conventional dehumidification system in hot and humid climates. Conventional dehumidification systems have many drawbacks that include high power consumption and increase the chlorofluorocarbon (CFC) level in the environment and major contribute to depletion of ozone layer. This paper discuss the functioning of dehumidification, cooling and air-conditioning systems using various solid desiccant with focus on the use of solar energy for dehumidification of humid air and regeneration of solid desiccant wheel. A comparative study of various dehumidification, cooling and air-conditioning systems show that solid desiccant has low operating and maintenance cost and is environment friendly.

Experimental investigations are carried out to study the influence of turning process parameters on fatigue performance of steel AISI 304-L. Cutting speed, feed rate and depth of cut are selected as experimental factors to be varied over a set of fatigue test runs. Using design of experiment study optimum combinations of cutting conditions was decided. As per ASTM standard smooth hourglass shape fatigue test specimens having gauge surface turned finished using setting of cutting condition as per DOE matrix were prepared on CNC lathe. Specimens are tested under constrained strain amplitude fatigue using fully integrated servo-hydraulic, axial fatigue test system. Strain amplitude of 0.3% is applied at cyclic frequency of 0.3 Hz. All tests are performed with same fatigue experimental setting. Test results are statistically analysed using response surface regression method and fatigue life prediction model with 95% accuracy is built. Individual and interaction effect of selected factors were studied using analysis of variance (ANOVA).

Testing of catalytic converter with exhaust gas recirculation system for diesel engine to reduce pollute gases is chosen for present work. The emphasis is given on hydrocarbon (HC), carbon monoxide (CO) and oxides of nitrogen. The catalytic converter was developed with variations of catalyst plates. Perforated plates of copper and combination of copper oxide and cerium oxide (CeO2 +CuO) were used as the catalyst. Copper spacer was used in between plates to vary the distance. Secondary air was injected into the converter to aid oxidization of HC and CO. Experimental study was carried out on computerized kirloskar single cylinder four stroke (10 B.H.P, 7.4 KW) diesel engine test rig with an eddy current dynamometer. The converter was tested with various combination with exhaust gas re-circulation (EGR) system. There are some improvements in the reduction and conversion efficiency of HC & CO. Exhaust gas re-circulation has proved to be effective in reducing NOx.

Testing of catalytic converter with exhaust gas recirculation system for diesel engine to reduce pollute gases is chosen for present work. The emphasis is given on hydrocarbon (HC), carbon monoxide (CO) and oxides of nitrogen. The catalytic converter was developed with variations of catalyst plates. Perforated plates of copper and combination of copper oxide and cerium oxide (CeO2 +CuO2) were used as the catalyst. Copper spacer is used in between plates to vary the distance. Secondary air was injected into the converter to aid oxidization of HC and CO. Experimental study was carried out on computerized kirloskar single cylinder four stroke (10 B.H.P, 7.4 KW) diesel engine test rig with an eddy current dynamometer. The converter was tested with various combination of the exhaust gas re-circulation (EGR) system. There are some improvements in the reduction and conversion efficiency of HC & CO. Exhaust gas recirculation has proved to be effective in reducing NOx.

Testing of catalytic converter with exhaust gas re-circulation system for diesel engine to reduce pollute gases is chosen for present work. The emphasis is given on hydrocarbon (HC), carbon monoxide (CO) and oxides of nitrogen. The catalytic converter was developed with variations of catalyst plates. Perforated plates of copper and combination of copper oxide and cerium oxide (CeO2 +CuO) were used as the catalyst. Copper spacer was used in between plates to vary the distance. Secondary air was injected into the converter to aid oxidization of HC and CO. Experimental study was carried out on computerized kirloskar single cylinder four stroke (10 B.H.P, 7.4 KW) diesel engine test rig with an eddy current dynamometer. The converter was tested with various combination with exhaust gas re-circulation (EGR) system. There are some improvements in the reduction and conversion efficiency of HC & CO. Exhaust gas re-circulation has proved to be effective in reducing NOx .Copyright © 2005 by ASME