| Double-row Steel-column-shaped-elliptical-tube Radiators is a kind of civil heating radiator commonly used in buildings in recent years.This type of radiator has a simple appearance,beautiful appearance,compact structure and large heat dissipation,so it can meet the requirements of current heating radiators.In the domestic market,production has continued to rise in recent years.This topic focuses on the new calculation method of heat dissipation in the vertical placement of Double-row Steel-column-shaped-elliptical-tube Radiators.Based on its working mechanism and heat transfer characteristics of the radiator,the research results are summarized.?t=64.5/44.5? two engineering methods for heat dissipation of such radiators.It is clear that the theoretical analysis method in the thermal calculation of the radiator is used to analyze the combination of the elliptical single tube to the whole radiator.Firstly,the heat transfer mechanism and the heat medium flow condition are summarized by using the principle of heat transfer.A single tube mathematical model(including heat exchange between a single tube and a heat medium,convection heat transfer in a single tube,and a single tube)is established.And Convective heat transfer and single tube tube external radiation heat transfer),the "qualitative temperature tm,stereotype size H1" involved in the theoretical calculation is selected.Then focus on the overall selection of the radiator,according to the composition of the external heat dissipation of the multi-column radiator(natural convection heat transfer and radiation heat transfer on the outer surface),set the natural convection Nusselt number criterion of the outer surface of the radiator as:Nuc=C(GrH1·Prf)n×(L1/a)m×(B/b)k;The calculation formula for the radiation heat transfer engineering of this type of radiator after simplified integration is proposed:(?)The samples of a large number of Double-row Steel-column-shaped-elliptical-tube Radiators were tested under standard working conditions?t=64.5/44.5?.Based on the experimental data,the related research on copper-aluminum-composite-column airfoil Radiators was combined with the classics.The similarity principle in heat transfer is calculated by multivariate nonlinear fitting calculation using data processing software.After the integration,the heat sink heat dissipation formula at excess temperature ? t=64.5/44.5? is obtained:(?)Using Steady-State Thermal software and Fluent software in ANSYS,the total heat dissipation,radiation heat transfer and natural convection heat transfer of 2,3,and 4 column steel radiators under new and old standard conditions were simulated.Comparing the experimental data with the theoretical calculation results,the rationality of the correction factor:?1=?2=?3=?4=……=?n-1?0.91 in the calculation formula of the radiator heat transfer engineering proposed in this thesis is verified.According to the actual engineering calculation,the flow state of the heat medium is different,the natural convection Nusselt number on the outer surface of the radiator is divided into two flow states:laminar flow and turbulent flow:(?)Through the actual comparison with the other 20 sets of different radiators heat dissipation,the two heat dissipation calculation methods are proposed in this thesis for Double-row Steel-column-shaped-elliptical-tube Radiators in the corresponding specifications and models are highly sexuality practical,and combined with the relevant error theory,makes an objective and fair evaluation of the research conclusions,so that make the conclusion has a higher degree of credibility within the scope of application.The above research results provide a reference for the design and development of Double-row Steel-column-shaped-elliptical-tube Radiators and other similar structural heat radiators,and also have reference significance for the calculation of heat dissipation in engineering. |
PDF Full Text Request