scholarly journals Wall heat flux measurements in a GO2/GH2 heat-sink combustion chamber

2018 ◽  
Vol 13 (1) ◽  
pp. JTST0016-JTST0016 ◽  
Author(s):  
Taiping WANG ◽  
Bing SUN ◽  
Jixin XIANG ◽  
Di LIU
Keyword(s):  
Heat Flux ◽  
Combustion Chamber ◽  
Heat Sink ◽  
Wall Heat Flux ◽  
Flux Measurements

Impact of Radiation on the Wall Heat Load at a Test Bench Gas Turbine Combustion Chamber: Measurements and CFD Simulation

2007 ◽  
Author(s):  
R. Dannecker ◽  
K.-U. Schildmacher ◽  
B. Noll ◽  
R. Koch ◽  
M. Hase ◽  
...  
Keyword(s):  
Heat Flux ◽  
Combustion Chamber ◽  
Gas Turbine ◽  
Heat Load ◽  
Thermal Design ◽  
Wall Heat Flux ◽  
Radiative Properties ◽  
Numerical Work ◽  
Gas Turbine Combustion ◽  
The Impact

Experimental and numerical work has been carried out to determine the wall heat load at the liner structure of a model gas turbine combustion chamber. Measured cross-sectional profiles of the velocity and temperature field inside the chamber could be used to validate various CFD calculations of the combustion flow. It turned out that only a special treatment of the thermal boundary conditions at all liner walls would actually lead to appropriate values of the wall heat flux. Radiation modeling included two radiative properties models (SG single gray gas and WSSG weighted sum of gray gases) and three radiation transport models (P1, DT discrete transfer, MC Monte Carlo). The performance of the WSGG model has been assessed with charts and the impact of the radiation on the liner wall temperature distribution has been studied. The experimental values are matched within 3% deviation with the best combination of transport and radiation property models. The radiation contributes to 20-30% of the total wall heat flux. The present approach enables Siemens PG to access the thermal design of combustors more precisely.

scholarly journals Transient Heat-Flux Measurements in the Combustion Chamber of a Spark-Ignition Engine

1982 ◽  
Vol 104 (1) ◽  
pp. 62-67 ◽  
Author(s):  
A. C. Alkidas ◽  
J. P. Myers
Keyword(s):  
Heat Flux ◽  
Combustion Chamber ◽  
Stoichiometric Composition ◽  
Spark Ignition ◽  
Volumetric Efficiency ◽  
Spark Ignition Engine ◽  
High Rate ◽  
Cycle Variation ◽  
Peak Heat Flux ◽  
Flux Measurements

Heat-flux measurements were obtained at several locations on the cylinder head and liner of a four-stroke, single-cylinder, spark-ignition engine. The variations of heat transfer with air-fuel ratio and volumetric efficiency were investigated. The magnitude of the heat flux was found to be highest at near-stoichiometric composition, whereas at either leaner or richer composition the heat flux decreased. An increase in volumetric efficiency from 40 to 60 percent resulted in an increase in peak heat flux of about 30 percent. The largest cycle-to-cycle variation in the measured heat flux occurred at the time of the initial high rate of heat flux. This is related to the cycle-to-cycle variation of flame propagation in the combustion chamber. Finally, the calculated amount of heat transferred to the walls of the combustion chamber during the closed portion of the engine cycle (intake valve closing to exhaust valve opening) agreed with the corresponding values obtained from the heat-flux measurements.

Detailed Analysis of the Thermal Wall Heat Load in Annular Combustors

1999 ◽  
Author(s):  
Werner Krebs ◽  
Günther Walz ◽  
Stefan Hoffmann ◽  
Hans Judith
Keyword(s):  
Heat Flux ◽  
Combustion Chamber ◽  
Heat Load ◽  
Thermal Power ◽  
Wall Heat Flux ◽  
Navier Stokes ◽  
Ceramic Tiles ◽  
Combustion Gases ◽  
Annular Combustor ◽  
Cooling Air

A detailed thermal analysis involving both measurements and calculations has been carried out in order to determine the wall heal load and to optimize the amount of cooling air for an annular combustor. In calculations, the convective wall heat flux has been detemined by application of a 3D Navier-Stokes Code. Furthermore, the radiation exchange between the hot combustion gases and the liner has been calculated using a multidimensional spectral approach. Although a quite high thermal power density is found within the combustion chamber the wall heat load is at a low level. Values are well below 80 kW/m2, due to the application of ceramic tiles which have a low thermal conductivity. The wall heat load is dominated by radiation emitted in the lower gas radiation bands (λ < 2.9 μm). The convective wall heat flux is nearly balanced out by the sealing air which is discharged through gaps between the ceramic tiles. The cooling effect of the sealing air, however, is strongly influenced by the 3D near wall flow field in the combustion chamber.

scholarly journals Wall Heat Flux Measurements for a Kerosene-Fueled Supersonic Combustor

2019 ◽  
Vol 32 (5) ◽  
pp. 04019080
Author(s):  
Di Cheng ◽  
Jing Wang ◽  
Yang Lu ◽  
Long Li ◽  
Wei Yao ◽  
...  
Keyword(s):  
Heat Flux ◽  
Wall Heat Flux ◽  
Flux Measurements

Unsteady Heat Flux Measurements in Agitated Channel Flows

2015 ◽  
Author(s):  
Smita Agrawal ◽  
Terrence Simon ◽  
Mark North ◽  
Tianhong Cui
Keyword(s):  
Heat Transfer ◽  
Heat Flux ◽  
Heat Exchanger ◽  
Convective Heat Transfer ◽  
Convective Heat ◽  
Central Region ◽  
Heat Sink ◽  
Rectangular Channel ◽  
Base Region ◽  
Flux Measurements

In this experiment, agitation is used in a rectangular channel for convective heat transfer enhancement. The channel under study is representative of a flow channel in an electronics cooling finned heat sink module. It is open at one end and has a translationally oscillating plate within it that agitates the flow. Contrary to the heat sink cooling channel, the test channel has no net through-flow so that agitation, isolated from throughflow effects, is studied. The channel is divided into three regions. The entry region is close to the open end of the channel. This would be near the fin tips in the finned heat exchanger channel. The base region is close to the other end of the channel where the flow makes an abrupt U-bend around the agitator plate. This is near the fin base region of a finned channel of a heat sink heat exchanger. The central region is between the two. Each region has special flow and convective heat transfer features for study. Ensemble-averaged velocities and RMS fluctuations of velocity are measured over the cycle. Measured data lend insight into the mixing phenomena in each region over the oscillation cycle. Unsteady heat flux measurements were made in each region and over the cycle to help in understanding the mechanisms affecting heat transfer. The unsteady heat flux characteristics in the entry and base regions seem to be more influenced by the RMS fluctuations of velocity, indicating that heat transfer in these regions is governed by turbulence generated by agitation. The unsteady heat flux trends in the central region seem to be more influenced by acceleration/deceleration of the flow than by turbulence-like structures.

Sign in / Sign up

Export Citation Format

Share Document