Heat transfer through a spiral tube with considering charging of nanoparticle-enhanced paraffin

The spirally water wall are distributed on the plane and divided into seven sections. The mean heat flux of each section is determined using furnace thermal calculation in sections. The value of the pressure and temperature concerning the working medium at inlet and outlet of each tube are established by calculating enthalpy increasing. The vaporizing processes of the working medium in the spiral tube under the three working conditions: 70%BMCR, 65%BMCR and 60%BMCR are analyzed. The state of the working medium and the possibility of the heat transfer deterioration are estimated. More reliable references are provided for the appearance of the heat transfer deterioration.

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Heat Transfer in Supercritical Steam Flowing Through Spiral Tubes

Journal of Heat Transfer ◽

10.1115/1.4047641 ◽

2020 ◽

Vol 142 (11) ◽

Author(s):

Deepak Kumar Kanungo ◽

Sachin Kumar Shrivastava ◽

Nand Kumar Singh ◽

Kirti Chandra Sahu

Keyword(s):

Heat Transfer ◽

Heat Flux ◽

Three Dimensional ◽

Tangential Velocity ◽

Thermal Conditions ◽

Strong Relationship ◽

High Heat ◽

High Heat Flux ◽

Straight Tube ◽

Spiral Tube

Abstract We investigate heat transfer in supercritical steam flowing in a spiral tube by conducting three-dimensional numerical simulations. The current numerical solver has been validated with the existing experimental results, and simulations are performed by varying different geometric parameters of a spiral tube. The flow dynamics and heat transfer in a spiral tube are compared against those in a straight tube. For the parameters range considered in the present study, it is found that the heat transfer coefficient (HTC) in the spiral tube is 29% higher than that in the case of a straight tube for the same flow and thermal conditions. Our results indicate that the tangential velocity component resulting due to the spiraling effect of the steam is the primary reason for the enhancement of the HTC value. It is observed that while the HTC in a spiral tube is inversely related to the spiral diameter, it does not exhibit a strong relationship with the spiral pitch. Moreover, three existing heat transfer correlations are evaluated under the spiral flow condition and it is observed that none of them can calculate the HTC value accurately in spiral tubes. Using the Buckingham π-theorem, three modified correlations are proposed for the low, moderate, and high heat flux regimes, which accurately predict the wall temperature and HTC of supercritical steam in spiral tubes in all the heat flux regimes. The correlations have an error band of less than ±20%.

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Study on the Conical Spiral Tube Bundle Heat Exchangers with Pulsation Flow Generator Structure

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.143-144.698 ◽

2011 ◽

Vol 143-144 ◽

pp. 698-702 ◽

Cited By ~ 1

Author(s):

Meng Ran Ge ◽

Ke Yan ◽

Pei Qi Ge ◽

Jun Gao

Keyword(s):

Heat Transfer ◽

Natural Frequency ◽

Heat Exchangers ◽

Heat Transfer Performance ◽

Tube Bundle ◽

Elastic Tube ◽

Transfer Performance ◽

Spiral Tube ◽

Flow Generator ◽

Planar Elastic Tube Bundle

Elastic tube bundles are universally used in heat transfer enhancement by flow-induced vibration in heat exchangers, and the study of the heat transfer performance is of importance. The structure of conical spiral tube bundle heat exchanger was introduced first, and the structure of pulsation flow generator was also introduced. The frequency of pulsation flow was discussed. Finally, in condition of same shell side diameter, the heat transfer and natural frequency of the conical spiral tube bundle were compared with the planar elastic tube bundle. The results show that the natural frequency of conical spiral tube bundle was smaller, the heat transfer performance of conical spiral tube bundle was better than the planar elastic tube bundle.

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Experimental and numerical investigation of convective heat transfer and fluid flow in twisted spiral tube

International Journal of Heat and Mass Transfer ◽

10.1016/j.ijheatmasstransfer.2015.06.068 ◽

2015 ◽

Vol 90 ◽

pp. 523-541 ◽

Cited By ~ 54

Author(s):

Xinyi Tang ◽

Xianfeng Dai ◽

Dongsheng Zhu

Keyword(s):

Heat Transfer ◽

Fluid Flow ◽

Convective Heat Transfer ◽

Numerical Investigation ◽

Convective Heat ◽

Spiral Tube

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Numerical study on heat transfer and flow resistance characteristics of multi-head twisted spiral tube

Thermal Science ◽

10.2298/tsci210224206z ◽

2021 ◽

pp. 206-206

Author(s):

Zhiqun Zheng ◽

Fayi Yan ◽

Lei Shi

Keyword(s):

Heat Transfer ◽

Numerical Calculation ◽

Cross Section ◽

Heat Transfer Performance ◽

Numerical Study ◽

Smooth Tube ◽

Transfer Performance ◽

Spiral Tube ◽

Inside Diameter ◽

The Cross

A numerical calculation model of multihead twisted spiral tube (MTST) was established. In the range of Reynolds number from 5000 to 35000, the influence of different twisted structure on the flow and heat transfer characteristics of the MTST was studied by numerical calculation. Numerical calculation results indicate that the Nusselt number and friction coefficient increase with the increase in the ratio of outside and inside diameter of the cross-section, the increase in the number of twisted nodes, and the increase in the number of twisted spiral tube heads. Under the condition of the same spiral structure and the same hydraulic diameter, the heat transfer performance of the MTST is better than that of the spiral smooth tube. In addition, through artificial neural network (ANN) analysis, the ratio of outside and inside diameter of the cross-section, number of twisted nodes, and the number of twisted spiral tube heads were optimized to promote the comprehensive heat transfer performance. The performance evaluation criterion is the highest when the ratio of outside and inside diameter of the cross-section is 25/22.5, the number of twisted nodes is 3, and the number of twisted spiral tube heads is 3, which is 1.849 of the spiral smooth tube.

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