Suscripción a Biblioteca: Guest
Página principal de la Biblioteca Digital de ICHMT Año actual Archivos Comité Ejecutivo Centro Internacional de Transferencia de Calor y Masa

Two-phase heat transfer inside minichannels: experimental measurements of the condensation heat transfer coefficient

Alberto Cavallini
Dipartimento di Fisica Tecnica, Universita di Padova, via Venezia 1,I-35131 Padova, Italy

Giuseppe Censi
Dipartimento di Fisica Tecnica, Universita di Padova, via Venezia 1,I-35131 Padova, Italy

Davide Del Col
University of Padova, Department of Industrial Engineering, Via Venezia 1, 35131 Padova, Italy

Luca Doretti
Dept. of Civil, Architectural and Environmental Engineering, University of Padova, Via Venezia 1, 35131, Padova - IT

Marko Matkovic
Dipartimento di Fisica Tecnica, Universita di Padova, via Venezia 1,I-35131 Padova, Italy

Luisa Rossetto
University of Padova, Department of Industrial Engineering, via Venezia 1, 35131 Padova, Italy

Claudio Zilio
Dept. of Management and Engineering, University of Padova, Str.lla S. Nicola, 1, VICENZA, 36100-Italy


This paper presents a new measuring technique for the heat transfer coefficient during condensation inside a 1.4 mm hydraulic diameter multiport minichannel tube. It also reports experimental data taken during condensation of R134a. The tube wall temperature is directly measured, so as to obtain the saturation to wall temperature difference and thus the internal heat transfer coefficient in a direct form.
The test section presented here is made of three counter-flow heat exchangers. It is realized with one 1.8 m long multiport tube and three separated jackets. The refrigerant condenses in the minichannels against the cooling water flowing in the jackets. The actual measuring sector is the third heat exchanger, considering the refrigerant flow direction. The other two heat exchangers are only used to achieve the desired value of vapor quality.
The test section has been designed with the purpose of achieving both high water-side heat transfer coefficients and good mixing of the cooling water during tests. The final design is the result of the Finite Volume Method modeling and prototype testing. The tests showed that the measured heat transfer coefficient does not depend on the water side coefficient.

ICHMT Digital Library

Bow shocks on a jet-like solid body shape. Thermal Sciences 2004, 2004. Pulsed, supersonic fuel jets - their characteristics and potential for improved diesel engine injection. PULSED, SUPERSONIC FUEL JETS - THEIR CHARACTERISTICS AND POTENTIAL FOR IMPROVED DIESEL ENGINE INJECTION
View of engine compartment components (left). Plots of temperature distributions in centreplane, forward of engine (right). CHT-04 - Advances in Computational Heat Transfer III, 2004. Devel... DEVELOPMENT AND CURRENT STATUS OF INDUSTRIAL THERMOFLUIDS CFD ANALYSIS
Pratt & Whitney's F-135 Joint Strike Fighter Engine under test in Florida is a 3600F class jet engine. TURBINE-09, 2009. Turbine airfoil leading edge stagnation aerodynamics and heat transfe... TURBINE AIRFOIL LEADING EDGE STAGNATION AERODYNAMICS AND HEAT TRANSFER - A REVIEW
Refractive index reconstructed field. (a) Second iteration. (b) Fourth iteration. Radiative Transfer - VI, 2010. Theoretical development for refractive index reconstruction from a radiative ... THEORETICAL DEVELOPMENT FOR REFRACTIVE INDEX RECONSTRUCTION FROM A RADIATIVE TRANSFER EQUATION-BASED ALGORITHM
Two inclusion test, four collimated sources. Radiative Transfer - VI, 2010. New developments in frequency domain optical tomography. Part II. Application with a L-BFGS associated to an inexa... NEW DEVELOPMENTS IN FREQUENCY DOMAIN OPTICAL TOMOGRAPHY. PART II. APPLICATION WITH A L-BFGS ASSOCIATED TO AN INEXACT LINE SEARCH