Simone Mancin - Academia.edu (original) (raw)

Papers by Simone Mancin

Journal of Physics: Conference Series, 2014

2008 2nd International Conference on Thermal Issues in Emerging Technologies, ThETA 2008, 2008

ABSTRACT This paper presents the experimental heat transfer and pressure drops measurements relat... more ABSTRACT This paper presents the experimental heat transfer and pressure drops measurements relative to single phase air flow through two different Aluminum foams, electrically heated. Because of their interesting heat transfer and mechanical properties, metal foams have been proposed for several different applications both thermal and structural. The tested Aluminum foams present 5 and 40 pores per inch (PPI) respectively and they have been inserted in a new test equipment located at the Department of Fisica Tecnica of the University of Padova. The experimental heat transfer coefficients and pressure drops have been collected by varying the air mass flow rate and the electrical power which has been set at 25.0, 32.5 and 40.0 kW m2. This paper aims to point out the effective thermal fluid dynamic behaviour of these new enhanced surfaces which present high heat transfer area per unit of volume at the expense of high pressure drop. Moreover, the results of several semi-empirical correlations for pressure gradient calculation have been compared with the collected experimental data points.

Proceedings of the ASME Summer Heat Transfer Conference 2009, HT2009, 2009

ABSTRACT Electronic cooling challenge is focused on the high heat flux to be dissipated by the op... more ABSTRACT Electronic cooling challenge is focused on the high heat flux to be dissipated by the operating fluid. Efficient heat spreaders and dissipators, and compact heat exchangers are in great demand for various applications. In the last decade, cellular structure materials and particularly open cells metal foams have been proposed as possible substitutes for traditional finned surfaces. Several authors have experimentally investigated the thermal performance of different metal foams and periodic heat transfer media. Metal foams present random microstructures that consist in open cells randomly oriented and mostly homogeneous in size and shape. Most commercially available metal foams are based on aluminum, copper, nickel and metal alloys. This paper presents the porosity effects on the thermal behaviour of different 10 PPI (pores per inch) metal foams tested in the experimental facility built at the Dept. of Fisica Tecnica of the University of Padova. In particular, the data points have been collected by varying independently the mass flow rate and the heat flow rate. The measured experimental heat transfer coefficients and the pressure drops for three metal foams with different porosity are compared.

2010 14th International Heat Transfer Conference, IHTC 14, 2010

ABSTRACT This paper presents the experimental heat transfer coefficient and pressure drop measure... more ABSTRACT This paper presents the experimental heat transfer coefficient and pressure drop measurements obtained during single phase air heat transfer through four 10 pores per inch (PPI) metal foams with different porosities and different foam core heights, 40 mm and 20 mm respectively. The specimens have been inserted in an open-circuit type wind channel with rectangular cross section. The effect of the foam core height on the heat transfer has been analysed by imposing three constant heat flow rates at the bottom plate of the samples: 250, 325 and 400 W and varying the air mass velocity between 0.005 and 0.025 kg m−2 s−1 at around atmospheric pressure. The temperatures of the base, of the upper plate and of the air, at the inlet and outlet of the test section, have been measured by means of several T-type calibrated thermocouples. The pressure drops during air flow through the samples are recorded by means of a high accuracy differential pressure transducer. The experimental results are presented in terms of heat transfer coefficient, normalised mean wall temperature, pressure gradient, permeability and inertia coefficient. The measured pressure gradients and heat transfer coefficients have been compared against the predictions of two different models recently developed by present authors.

Journal of Physics: Conference Series, 2012

Air is a cheap and safe fluid, widely used in electronic, aerospace and air conditioning applicat... more Air is a cheap and safe fluid, widely used in electronic, aerospace and air conditioning applications. Because of its poor heat transfer properties, it always flows through extended surfaces, such as finned surfaces, to enhance the convective heat transfer. In this paper, experimental results are reviewed and numerical studies during air forced convection through extended surfaces are presented. The thermal and hydraulic behaviours of a reference trapezoidal finned surface, experimentally evaluated by present authors in an open-circuit wind tunnel, has been compared with numerical simulations carried out by using the commercial CFD software COMSOL Multiphysics. Once the model has been validated, numerical simulations have been extended to other rectangular finned configurations, in order to study the effects of the fin thickness, fin pitch and fin height on the thermo-hydraulic behaviour of the extended surfaces. Moreover, several pin fin surfaces have been simulated in the same range of operating conditions previously analyzed. Numerical results about heat transfer and pressure drop, for both plain finned and pin fin surfaces, have been compared with empirical correlations from the open literature, and more accurate equations have been developed, proposed, and validated.

Journal of Physics: Conference Series, 2012

ABSTRACT Metal foams are a class of cellular structured materials with open cells randomly orient... more ABSTRACT Metal foams are a class of cellular structured materials with open cells randomly oriented and mostly homogeneous in size and shape. In the last decade, several authors have discussed the interesting heat transfer capabilities of these materials as enhanced surfaces for air conditioning, refrigeration, and electronic cooling applications. This paper reports an assessment on the forced convection through metal foams presenting experimental and analytical results carried out during air heat transfer through twelve aluminum foam samples and nine copper foam samples. The metal foam samples present different numbers of pores per linear inch (PPI), which vary between 5 and 40 with a porosity ranging between 0.896-0.956 samples of different heights have been studied. From the experimental measurements two correlations for the heat transfer coefficient and pressure drop calculations have been developed. These models can be successfully used to optimize different foam heat exchangers for any given application.

International Journal of Refrigeration, 2013

ABSTRACT This paper presents recent measurements of heat transfer coefficient obtained during con... more ABSTRACT This paper presents recent measurements of heat transfer coefficient obtained during condensation of R32 inside a commercial brazed plate heat exchanger (BPHE). The experimental data show the effect of refrigerant mass velocity, vapor quality, temperature difference (saturation-to-wall) and inlet vapor superheating. In particular, the specific mass velocity is varied between 15 and 40 kg m−2 s−1 and the outlet vapor quality between 0.0 and 0.65, while inlet vapor superheating goes from 5 to 25 K. The saturation temperature is kept constant at around 36.5 °C, which can be considered a usual temperature level for water cooled heat pump applications. The present authors provide a numerical procedure to calculate the condensation heat transfer in the BPHE, accounting also for the superheating effect. This model is assessed by comparisons with the experimental measurements relative to R32, R410A, and R744.

International Journal of Thermal Sciences, 2013

Journal of Physics: Conference Series, 2014

2008 2nd International Conference on Thermal Issues in Emerging Technologies, ThETA 2008, 2008

ABSTRACT This paper presents the experimental heat transfer and pressure drops measurements relat... more ABSTRACT This paper presents the experimental heat transfer and pressure drops measurements relative to single phase air flow through two different Aluminum foams, electrically heated. Because of their interesting heat transfer and mechanical properties, metal foams have been proposed for several different applications both thermal and structural. The tested Aluminum foams present 5 and 40 pores per inch (PPI) respectively and they have been inserted in a new test equipment located at the Department of Fisica Tecnica of the University of Padova. The experimental heat transfer coefficients and pressure drops have been collected by varying the air mass flow rate and the electrical power which has been set at 25.0, 32.5 and 40.0 kW m2. This paper aims to point out the effective thermal fluid dynamic behaviour of these new enhanced surfaces which present high heat transfer area per unit of volume at the expense of high pressure drop. Moreover, the results of several semi-empirical correlations for pressure gradient calculation have been compared with the collected experimental data points.

Proceedings of the ASME Summer Heat Transfer Conference 2009, HT2009, 2009

ABSTRACT Electronic cooling challenge is focused on the high heat flux to be dissipated by the op... more ABSTRACT Electronic cooling challenge is focused on the high heat flux to be dissipated by the operating fluid. Efficient heat spreaders and dissipators, and compact heat exchangers are in great demand for various applications. In the last decade, cellular structure materials and particularly open cells metal foams have been proposed as possible substitutes for traditional finned surfaces. Several authors have experimentally investigated the thermal performance of different metal foams and periodic heat transfer media. Metal foams present random microstructures that consist in open cells randomly oriented and mostly homogeneous in size and shape. Most commercially available metal foams are based on aluminum, copper, nickel and metal alloys. This paper presents the porosity effects on the thermal behaviour of different 10 PPI (pores per inch) metal foams tested in the experimental facility built at the Dept. of Fisica Tecnica of the University of Padova. In particular, the data points have been collected by varying independently the mass flow rate and the heat flow rate. The measured experimental heat transfer coefficients and the pressure drops for three metal foams with different porosity are compared.

2010 14th International Heat Transfer Conference, IHTC 14, 2010

ABSTRACT This paper presents the experimental heat transfer coefficient and pressure drop measure... more ABSTRACT This paper presents the experimental heat transfer coefficient and pressure drop measurements obtained during single phase air heat transfer through four 10 pores per inch (PPI) metal foams with different porosities and different foam core heights, 40 mm and 20 mm respectively. The specimens have been inserted in an open-circuit type wind channel with rectangular cross section. The effect of the foam core height on the heat transfer has been analysed by imposing three constant heat flow rates at the bottom plate of the samples: 250, 325 and 400 W and varying the air mass velocity between 0.005 and 0.025 kg m−2 s−1 at around atmospheric pressure. The temperatures of the base, of the upper plate and of the air, at the inlet and outlet of the test section, have been measured by means of several T-type calibrated thermocouples. The pressure drops during air flow through the samples are recorded by means of a high accuracy differential pressure transducer. The experimental results are presented in terms of heat transfer coefficient, normalised mean wall temperature, pressure gradient, permeability and inertia coefficient. The measured pressure gradients and heat transfer coefficients have been compared against the predictions of two different models recently developed by present authors.

Journal of Physics: Conference Series, 2012

Air is a cheap and safe fluid, widely used in electronic, aerospace and air conditioning applicat... more Air is a cheap and safe fluid, widely used in electronic, aerospace and air conditioning applications. Because of its poor heat transfer properties, it always flows through extended surfaces, such as finned surfaces, to enhance the convective heat transfer. In this paper, experimental results are reviewed and numerical studies during air forced convection through extended surfaces are presented. The thermal and hydraulic behaviours of a reference trapezoidal finned surface, experimentally evaluated by present authors in an open-circuit wind tunnel, has been compared with numerical simulations carried out by using the commercial CFD software COMSOL Multiphysics. Once the model has been validated, numerical simulations have been extended to other rectangular finned configurations, in order to study the effects of the fin thickness, fin pitch and fin height on the thermo-hydraulic behaviour of the extended surfaces. Moreover, several pin fin surfaces have been simulated in the same range of operating conditions previously analyzed. Numerical results about heat transfer and pressure drop, for both plain finned and pin fin surfaces, have been compared with empirical correlations from the open literature, and more accurate equations have been developed, proposed, and validated.

Journal of Physics: Conference Series, 2012

ABSTRACT Metal foams are a class of cellular structured materials with open cells randomly orient... more ABSTRACT Metal foams are a class of cellular structured materials with open cells randomly oriented and mostly homogeneous in size and shape. In the last decade, several authors have discussed the interesting heat transfer capabilities of these materials as enhanced surfaces for air conditioning, refrigeration, and electronic cooling applications. This paper reports an assessment on the forced convection through metal foams presenting experimental and analytical results carried out during air heat transfer through twelve aluminum foam samples and nine copper foam samples. The metal foam samples present different numbers of pores per linear inch (PPI), which vary between 5 and 40 with a porosity ranging between 0.896-0.956 samples of different heights have been studied. From the experimental measurements two correlations for the heat transfer coefficient and pressure drop calculations have been developed. These models can be successfully used to optimize different foam heat exchangers for any given application.

International Journal of Refrigeration, 2013

ABSTRACT This paper presents recent measurements of heat transfer coefficient obtained during con... more ABSTRACT This paper presents recent measurements of heat transfer coefficient obtained during condensation of R32 inside a commercial brazed plate heat exchanger (BPHE). The experimental data show the effect of refrigerant mass velocity, vapor quality, temperature difference (saturation-to-wall) and inlet vapor superheating. In particular, the specific mass velocity is varied between 15 and 40 kg m−2 s−1 and the outlet vapor quality between 0.0 and 0.65, while inlet vapor superheating goes from 5 to 25 K. The saturation temperature is kept constant at around 36.5 °C, which can be considered a usual temperature level for water cooled heat pump applications. The present authors provide a numerical procedure to calculate the condensation heat transfer in the BPHE, accounting also for the superheating effect. This model is assessed by comparisons with the experimental measurements relative to R32, R410A, and R744.

International Journal of Thermal Sciences, 2013