| Comparing with traditional baffle heat exchanger, rod baffle heat exchanger has theadvantage of the high efficiency of heat transfer, small fluid resistance, goodanti-flow-induced vibration. U.S. Philip presents the empirical formula of baffle rod heatexchanger shell flow and heat transfer based on experimental correlations, which is based on alot of experimental studies on the rod baffle heat exchanger heat transfer and flow calculation.This method is a holistic approach to study the impact of the structure on the flow and heattransfer rod baffle heat exchanger shell. In this paper, the square cloth tube rod baffle heatexchanger is divided into X, C, E three flow paths to study the rod baffle heat exchanger, inaccordance with the characteristics of the flow path of rod baffle heat exchanger. The X flowpath as the mainstream road, C, E flow paths as the interference roads, study the influence ofeach flow path on rod baffle heat exchanger shell pass heat transfer and fluid flowstep-by-step. The main work of this paper includes:1. Through the analysis of separate X flow path square cloth tube rod baffle heatexchanger, X, C mixed flow path square cloth tube rod baffle heat exchanger and full flowpath square cloth tube rod baffle heat exchanger, using the way of dimensional analysis todetermine the dimensionless number and the required number of models of each of these threeheat exchangers.2. On the basis of a reasonable simplification of the actual structure, build three differentmodels of the square cloth tube rod baffle heat exchanger as is said above. Implement thethree-dimensional numerical simulation of each square cloth tube rod baffle heat exchanger inthe way of " piecewise modeling, piecewise grid, integration of the whole" with fluentsoftware.3. With the multiple linear fitting function of Matlab, get empirical relationship formulasof each of the three square cloth tube rod baffle heat exchangers shell pass heat transfer andfluid flow. Discuss interference effects of the C flow path and E flow path, sort out thequasi-logarithmic relationship of the C flow path and E flow path, including the interferenceeffects.4. Build a square cloth tube rod baffle heat exchanger, verify the correctness ofinterference formula.5. Build a triangular cloth tube rod baffle heat exchanger, compared to the verifiedsimulation results of square cloth tube rod baffle heat exchanger, tentative exploration about the influence of tube layout on the rod baffle heat exchanger shell pass heat transfer and fluidflow.The final conclusion: The interference effects of C flow path has a significant impact onthe rod baffle heat exchanger performance, C flow path larger, the performance of the rodbaffle heat exchanger shell pass heat transfer better, but increase the resistance lossmeanwhile, therefore, from the energy efficiency perspective, the size of C flow path mayexist an optimal value. E flow path generally is considered to be short, but this study findsthat the size of E flow path also has a certain impact on the rod baffle heat exchangerperformance, E flow path larger, shell pass heat transfer performance lower, but also followedthe decline of resistance losses. Besides, the empirical formula of square cloth tube rod baffleheat exchanger shell pass heat transfer and fluid flow is consistent with the verified modelwell. Compared with two different ways of tube layouts of rod baffle heat exchanger, theoverall performance of triangular cloth tube rod baffle heat exchanger is better. |
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