scholarly journals Experimental Measurements of the Volumetric Heat Transfer Coefficient between Forced Air and Sand at Reynold’s Numbers Relevant to Smouldering Combustion

Author(s):  
Marco A. B. Zanoni ◽  
Jason I. Gerhard ◽  
Jose L. Torero
Author(s):  
Simon Jacobi ◽  
Budimir Rosic

This paper presents a thermal investigation of the Integrated Combustor Vane concept for power generation gas turbines with individual can combustors. This concept has the potential to replace the high-pressure turbine’s first vanes by prolonged combustor walls. Experimental measurements are performed on a linear high-speed cascade consisting of two can combustors and two integrated vanes. The modularity of the facility allows for the testing at engine-realistic high turbulence levels, as well as swirl strengths with opposing swirl directions. The heat transfer characteristics of the integrated vanes are compared to conventional nozzle guide vanes. The experimental measurements are supported by detailed numerical simulations using the inhouse CFD code TBLOCK. Experimental as well as numerical results congruently indicate a considerable reduction of the heat transfer coefficient (HTC) on the integrated vanes surfaces and endwalls caused by a differing state of boundary layer thickness. The studies furthermore depict a slight, non-detrimental shift in the heat transfer coefficient distributions and the strength of the integrated vanes secondary flows as a result of engine-realistic combustor swirl.


1971 ◽  
Vol 49 (6) ◽  
pp. 833-838 ◽  
Author(s):  
T. F. Saldin ◽  
N. Barthakur

Heat transfer was studied from intact leaves of greenhouse-grown Phaseolus vulgaris L. under still and forced air conditions. Microwaves were used to heat the leaves without disturbing the thermal equilibrium of the environment. Leaf temperatures were measured by thermocouples and an infrared radiometer. Convective heat transfer coefficient for a leaf was obtained by two experimental methods and compared with the theoretical results. The unsteady-state method proved to be quite satisfactory.Typical values of heat transfer coefficient for free convection varied from 1.86 × 10−4 to 3.64 × 10−4 cal cm−2 s−1 °C−1, as the temperature difference between the leaf surface and the surrounding air increased from 1.0 to 3.9 °C. Forced convective heat transfer coefficient, however, increased to about 10 × 10−4 cal cm−2 s−1 °C−1 at 610 cm s−1.


2008 ◽  
Vol 130 (12) ◽  
Author(s):  
Vinod Narayanan ◽  
Murty Kanury ◽  
Jeromy Jenks

A modified heat exchanger analysis is developed here that accounts for a heat source, which is assumed to be volumetrically uniform in the hot fluid. The motivation for this work arises from the analysis of an ammonia-water absorber heat exchanger where a heat-of-absorption source term arises in the solution side. Utility of the analysis in deducing the overall heat transfer coefficient from experimental measurements is demonstrated.


2016 ◽  
Vol 139 (2) ◽  
Author(s):  
Simon Jacobi ◽  
Budimir Rosic

This paper presents a thermal investigation of the integrated combustor vane concept for power generation gas turbines with individual can combustors. This concept has the potential to replace the high-pressure turbine’s first vanes by prolonged combustor walls. Experimental measurements are performed on a linear high-speed cascade consisting of two can combustors and two integrated vanes. The modularity of the facility allows for the testing at engine-realistic high turbulence levels, as well as swirl strengths with opposing swirl directions. The heat transfer characteristics of the integrated vanes are compared to conventional nozzle guide vanes. The experimental measurements are supported by detailed numerical simulations using the in-house computational fluid dynamics (CFD) code TBLOCK. Experimental as well as numerical results congruently indicate a considerable reduction of the heat transfer coefficient (HTC) on the integrated vanes surfaces and endwalls caused by a differing state of boundary layer thickness. The studies furthermore depict a slight, nondetrimental shift in the heat transfer coefficient distributions and the strength of the integrated vanes secondary flows as a result of engine-realistic combustor swirl.


Sign in / Sign up

Export Citation Format

Share Document