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Abstract-In this study, heat transfer from a moving isothermal hot plate due to double impinging vertical slot jets was investigated for a laminar flow. The rectangular geometry consists of a confining adiabatic wall placed parallel to the moving impingement. The jets are located symmetrically at mid point of upper wall. Water and Al 2 O 3 nanoparticles mixture with different volumetric fraction was used as working medium. In considered jet impingement problem, the effects of the jet exit Reynolds numbers, ranging from 50 to 200, the normalized plate velocity, ranging from 0 to 2, and volumetric fractions of nanofluid, ranging from 0% to 6% were investigated. The commercial software package based on finite volume method FLUENT (version 6.3.26) is used in this study for the computations. It has been observed that increasing normalized plate velocity increases the heat transfer from bottom surface. Similarly, increasing Reynolds number of slot jets leads to enhancement of heat transfer. Besides, increasing volumetric fraction of nanofluid conributes to heat transfer enhancement.

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Honey pasteurization is one of the important steps of honey processing which requires thermal energy to elevate temperature of the honey to inactivate enzymes and to inhibit bacteria. Common technique used for thermal treatment of honey is batch jacketed pasteurizer driven by electrical resistance to heat water, oil or steam. Each heating approach requires high amount of energy which is transferred directly or indirectly to the honey. Furthermore, heat generation is expensive and there are several steps which cause energy and exergy loses such as boiler, heater, pipe, heating medium, wall thickness of the vessel etc. Alternatively, induction is a technology using electromagnetic heating with unique advantages as heating metal surfaces directly and effectively. Inductive heating has been used for some industries as metallurgy, however, possible food applications such as batch pasteurization was not studied in detail. The objective of this research is comparing energy and exergy efficiencies of conventional jacketed vessel heater and inductive heater for honey pasteurization. Consequently, inductive method was found more beneficial compared to commercial method in terms of energy and exergy efficiency.

The efficient use of existing energy sources along with the development and widespread use of alternative energy sources, especially renewable energy sources becoming important issues. At this point, the energy content of municipal solid wastes (MSW) can be considered a renewable energy source. MSWs contain a large fraction of renewable material and are continuously produced as a result of human activity. Therefore, international authorized institutions such as the U.S. Department of Energy (US DOE), and the U.S. Environmental Protection Agency (US EPA) assess MSWs as renewable and sustainable energy sources. Incineration is one of the options for energy recovery from MSW as a waste-to-energy (WTE) approach. The R1 energy efficiency is a criterion introduced by the European Union Waste Directive (Directive 2008/98/EC) to differentiate waste operation by incineration as either disposal or energy recovery. The paper focused on the evaluation of the MSW incineration potential of İzmir province in consideration of R1 energy efficiency criteria. According to the R1, the MSW energy recovery (both heat and electricity) potentials were investigated considering the amount, composition, and calorific value of MSW generated in İzmir province. The population growth, MSW generation, and calorific value alternation up to 2026 were estimated for İzmir. Based on MSW future projections of İzmir province, overall energy recovery potential was assessed. It is forecasted that the average net calorific value (NCV) of MSW generated in İzmir will exceed 6 MJ/kg. This NCV will be suitable for energy recovery from the İzmir MSW. Assuming R1=0.65, it is predicted that a minimum of 2231 GWh/year of heat energy or 932 GWh/year of electricity can be produced annually in the next years 2022.

have been gradually getting importance in industrial applications due to offering outstanding benefits. The current study has focused on the development of a numerical model to predict the thermal performance of the microchannel air preheaters (MCPH) for HVAC systems. An experimental study has been performed to validate the numerical model results. A louvered fin multiport microchannel heat exchanger has been employed as an air preheater in the experiments. The proposed model has been developed based on the segment-bysegment approach and calculated the outlet temperature and heat capacity of the MCPH. Different air velocities at the frontal face and varying mass flow rates in passes of the MCPH have been taken into consideration in the model. It has been concluded from experimental data that the model predicts the outlet temperature with an average absolute deviation within ±2% for all investigated test conditions. The proposed model shows high accuracy with respect to temperature calculation. Another conclusion is that the non-uniform air velocity approach improves the precision of the proposed model. The heat capacity predictions with the uniform air velocity approach indicate higher deviations than the non-uniform air velocity approach. Microchannel heat exchanger Microchannel preheater Numerical modeling R600a Thermal characteristics

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