Characterizing Heat Transfer in sCO2 Cycle Coolers Utilizing the Wilson Plot Technique

2021 ◽  
Author(s):  
Matthew Searle ◽  
Sridharan Ramesh ◽  
Douglas Straub
Keyword(s):  
Heat Transfer ◽  
Wilson Plot

scholarly journals Uncertainty analysis for experimental heat transfer data obtained by the Wilson plot method: Application to condensation on horizontal plain tubes

2013 ◽  
Vol 17 (2) ◽  
pp. 471-487 ◽  
Author(s):  
Francisco Uhía ◽  
Antonio Campo ◽  
José Fernández-Seara
Keyword(s):  
Heat Transfer ◽  
Experimental Data ◽  
Uncertainty Analysis ◽  
Transfer Problem ◽  
Experimental Program ◽  
Design Parameters ◽  
Accurate Estimation ◽  
Analytical Methodology ◽  
Wilson Plot ◽  
Plot Experiment

The accurate estimation of convection coefficients constitutes a crucial issue in designing and sizing any type of heat exchange device. The Wilson plot method and its subsequent modifications deliver a suitable procedure to estimate the convection coefficients from the post-processing of experimental data in a multitude of convective heat transfer processes. Uncertainty analysis is a powerful tool not only for handling the data and reporting coherent results of a certain experimental program, but also is a valuable tool in those stages devoted to the experimental design. This paper details the application of an analytical methodology for calculating the uncertainty associated with experimental data obtained by the Wilson plot method. Results based on a representative Wilson plot experiment to measure the condensation coefficients of R-134a over a horizontal 19 mm diameter smooth tube are shown. A parametric analysis was carried out sequentially to investigate the influence of the uncertainties in the measured variables and design parameters of the Wilson plot experiment in the results uncertainties. Although the example presented in this paper relates to a specific heat transfer process, the technique turns out to be rather general and can be extended to any heat transfer problem.

scholarly journals QUANTIFICATION OF ERRORS IN THE WILSON PLOT APPLIED TO CONDENSATION ON THE OUTSIDE OF TUBES

2010 ◽  
Vol 41 (1) ◽  
pp. 31-41
Author(s):  
Bryce M. Burnside ◽  
Bodius Salam ◽  
David A. McNeil
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Coefficient ◽  
Transfer Coefficient ◽  
Temperature Drop ◽  
Cross Flow ◽  
Random Errors ◽  
Horizontal Tubes ◽  
Flow Situation ◽  
Wilson Plot

In condensation over horizontal tubes where the wall temperature is not measured directly, the Wilson plot is used to determine the cooling side heat transfer coefficient. Conventionally, the variation in Nusselt number, Nu, with condensate side temperature drop, DTs, which accompanies change of cooling side flowrate, is assumed to be Nu µ 1/DTsn with n = 0.25. This is the free convention condensation value. In this paper a technique is devised, not only to check the accuracy of this assumption in the usual vapor side cross flow situation, but also to determine the effect on this accuracy of allowing the index n to vary. In a case study the best agreement between DTs assumed and the value obtained using the cooling side heat transfer coefficient which resulted from the Wilson plot, occurred at n = 0.21. Based on the random errors in the measured data, a linear regression taking into account the errors in both Wilson plot coordinates gave the cooling side heat transfer coefficient and its uncertainty.Keywords: Heat transfer; condensation; Wilson plots.DOI: 10.3329/jme.v41i1.5360Journal of Mechanical Engineering, Vol. ME 41, No. 1, June 2010 31-41

Experimental apparatus for measuring heat transfer coefficients by the Wilson plot method

2005 ◽  
Vol 26 (3) ◽  
pp. N1-N11 ◽  
Author(s):  
José Fernández-Seara ◽  
Francisco José Uhía ◽  
Jaime Sieres ◽  
Antonio Campo
Keyword(s):  
Heat Transfer ◽  
Transfer Coefficients ◽  
Heat Transfer Coefficients ◽  
Experimental Apparatus ◽  
Wilson Plot

scholarly journals Measurement of Convective Heat Transfer Coefficients With Supercritical CO2 Using the Wilson-Plot Technique

2020 ◽  
Vol 142 (7) ◽  
Author(s):  
Jim Black ◽  
Doug Straub ◽  
Ed Robey ◽  
Joe Yip ◽  
Sridharan Ramesh ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Heat Exchange ◽  
Convective Heat Transfer ◽  
Convective Heat ◽  
Smooth Tube ◽  
Transfer Coefficients ◽  
Heat Transfer Coefficients ◽  
Friction Factors ◽  
Wilson Plot ◽  
Convective Heat Transfer Coefficients

Abstract This paper describes the measurement of convective heat transfer coefficients and friction factors for sCO2 flowing in a smooth tube and compares the results with published correlations for validation. The paper also describes the Heat Exchange and Experimental Testing (HEET) rig recently designed and built at the U.S. Department of Energy’s (DoE’s) National Energy Technology Laboratory (NETL) in Morgantown, WV. The Wilson-plot technique used for measuring the heat transfer coefficients is described along with the data reduction process. The Wilson-plot technique was chosen as the basis for the design of NETL’s HEET rig. Advantages of the Wilson-plot technique include the (1) ability to measure high convective heat transfer coefficients accurately, (2) ability to measure average heat transfer coefficient for complicated heat exchange geometries like those produced using additive manufacturing, (3) ability to measure heat transfer coefficients on both sides of a heat exchanger independently, and (4) simplicity of experimental setup. Capabilities of the HEET rig include pressure to 24 MPa (3500 psig), temperature to 538 °C (1000 °F), mass flow rate to 1.5 kg/s (3 lb/s), and Re to 500,000. The rig is designed to operate with pure CO2 or a mixture of CO2 and up to 10% N2 by volume to study the impact of gas mixtures typical of direct-fired sCO2 power cycles on the convective heat transfer and pressure drop. Preliminary tests in the HEET rig were performed with smooth stainless-steel tube and pure CO2, and the results were compared with published correlations for Nusselt number (Nu) and friction factor. Over a Reynolds number (Re) range from 58,000 to 228,000, measured Nu was compared to predictions using the Dittus and Boelter equation (Kreith and Bohn, 1993, “Principles of Heat Transfer, West Publishing Company”) within 5% and measured friction factors were compared to predictions using the McAdams correlation (“McAdams, 1954, “Heat Transmission,” 3rd ed., McGraw Hill, New York)” for smooth tube to be within 5%.

scholarly journals Heat Transfer Coefficients in Concentric Annuli

2002 ◽  
Vol 124 (6) ◽  
pp. 1200-1203 ◽  
Author(s):  
Jaco Dirker ◽  
Josua P. Meyer
Keyword(s):  
Heat Transfer ◽  
Convective Heat Transfer ◽  
Convective Heat ◽  
Heat Transfer Correlation ◽  
Transfer Coefficients ◽  
Number Range ◽  
Heat Transfer Coefficients ◽  
Nusselt Numbers ◽  
Wide Range ◽  
Wilson Plot

The geometric shape of a passage’s cross-section has an effect on its convective heat transfer capabilities. For concentric annuli, the diameter ratio of the annular space plays an important role. The purpose of this investigation was to find a correlation that will accurately predict heat transfer coefficients at the inner wall of smooth concentric annuli for turbulent flow of water. Experiments were conducted with a wide range of annular diameter ratios and the Wilson plot method was used to develop a convective heat transfer correlation. The deduced correlation predicted Nusselt numbers accurately within 3 percent of measured values for annular diameter ratios between 1.7 and 3.2 and a Reynolds number range, based on the hydraulic diameter, of 4 000 to 30,000.

Sign in / Sign up

Export Citation Format

Share Document