Das Likhan, Aslfattahi Navid, Habib Khairul, Saidur R, Das Anupom, Kadirgama Kumaran
Department of Industrial and Manufacturing Systems Engineering, Iowa State University, 515 Morrill Road, Iowa, Ames, 50011, USA.
Department of Fluid Mechanics and Thermodynamics, Faculty of Mechanical Engineering, Czech Technical University in Prague, Technická 4, 166 07 Prague, Czech Republic.
Heliyon. 2023 Mar 9;9(3):e14283. doi: 10.1016/j.heliyon.2023.e14283. eCollection 2023 Mar.
MXene-based nanofluids are novel trends with improved dispersion stability and thermophysical characteristics over previously established nanofluids. In the present work, the thermohydraulic characteristics of a double pipe heat exchanger (DPHEX) with a Therminol55(TH55)/MXene + AlO nanofluid and various geometrically shaped (triangular, rectangular) ribbed twisted tape (TT) inserts are numerically investigated using the ANSYS Fluent interface. A counter flow arrangement with three different types of inserts (RRTT, TRTT, TT) and TH55/MXene + AlO nanofluid at 0.20 wt% are studied inside the heat exchanger. Adding ribbed inserts to the conventional TT insert enhances the turbulence intensity by creating extra vortices. The thermal boundary layer grows thinner due to increased axial and radial velocity. Due to the substantial flow obstruction, adding ribs increases the overall pressure drop between the inlet and outlet. The maximum increase in is 11.04 % using nanofluid instead of water, whereas the combination of insert and nanofluid exhibited up to 105 % enhancement for rectangular-ribbed TT compared to the plain tube. Nevertheless, the pressure decrease is found to be maximum in rectangular-ribbed TT because of significant flow disruption. This was likewise true with triangular-ribbed TT and TT insert. According to the PEC assessment, the RRTT insert had a maximum PEC value of 1.67 greater than TRTT and traditional TT for both TH55 and nanofluid flowing inside the tube. To summarize, the combination of TH55/MXene + AlO RRTT insert may be a promising choice for improving heat exchanger performance in a new generation efficient thermal system.
与先前已有的纳米流体相比，基于MXene的纳米流体是具有改善的分散稳定性和热物理特性的新趋势。在本工作中，使用ANSYS Fluent界面数值研究了带有Therminol55（TH55）/MXene + AlO纳米流体以及各种几何形状（三角形、矩形）的带肋扭带（TT）插入件的双管换热器（DPHEX）的热工水力特性。在换热器内部研究了具有三种不同类型插入件（矩形肋扭带、三角形肋扭带、扭带）以及0.20 wt%的TH55/MXene + AlO纳米流体的逆流布置。在传统扭带插入件上添加肋条通过产生额外的漩涡增强了湍流强度。由于轴向和径向速度增加，热边界层变薄。由于显著的流动阻碍，添加肋条增加了进出口之间的总压降。使用纳米流体代替水时，最大增加为11.04%，而与光管相比，插入件和纳米流体的组合使矩形肋扭带的传热增强高达105%。然而，由于显著的流动干扰，发现矩形肋扭带中的压力降最大。三角形肋扭带和扭带插入件也是如此。根据PEC评估，对于管内流动的TH55和纳米流体，矩形肋扭带插入件的最大PEC值比三角形肋扭带和传统扭带大1.67。总之，TH55/MXene + AlO矩形肋扭带插入件的组合可能是新一代高效热系统中提高换热器性能的一个有前景的选择。
