International Research Journal of Engineering and Technology (IRJET)
e-ISSN: 2395-0056
Volume: 10 Issue: 07 | July 2023
p-ISSN: 2395-0072
www.irjet.net
CAD modeling of fluid domain with twisted tape inserts using Creo Design software Shailesh Pandey1, Purushottam Sahu2, Ghanshyam Dhanera3 1 Research Scholar, BM College of Technology, Indore
2Professor and HEAD, BM College of Technology, Indore 3 Assistant Professor, BM College of Technology, Indore, MP ---------------------------------------------------------------------***--------------------------------------------------------------------gradients or temperature variations are crucial for heat Abstract - This study aimed to analyze the effect of outer
transmission among liquids or from the liquid to the surroundings.
and inner tube flow rates on heat transfer coefficients in a tube-in-tube helical coil heat exchanger using computational fluid dynamics (CFD) analysis. The CFD simulation employed a fluid mixture of Al2O3/water with a 1% volume fraction, and different fluid inlet velocities ranging from 0.01m/s to 0.05m/s were examined. Several parameters, including temperature distribution, pressure drop, heat transfer coefficient, and Nusselt number, were compared. The Nusselt number comparison curve indicated that CuO/water nanofluids with a 1% volume fraction exhibited the lowest Nusselt number, while a slightly higher Nusselt number was observed for CuO/water nanofluids with a 2% volume fraction. Notably, the highest heat transfer characteristics were observed for Al2O3/water with a 1% volume fraction due to the enhanced thermal conduction in the 1% Al2O3 vapor component of the fluid.
Heat exchangers find widespread use in the heating and cooling of fluids, as well as in processes such as evaporation and condensation. They are also employed in applications such as sterilization and pasteurization. In heat exchangers, fluids are segregated by walls to prevent intermixing, and such heat exchangers are referred to as retrievers. The application of nanofluids in heat exchangers is a promising approach to address the issue of low thermal conduction and reduced efficiency in complex fluid systems. When the thermal properties of the fluid are enhanced, it becomes possible to improve heat transmission within heat exchangers, which in turn allows for more compact designs. One effective method is to increase the heat-carrying capacity by introducing finely dispersed particles into the fluid.
Key Words: Heat Transfer, Pressure Drop, Reynolds Number, Nusselt number, CFD Model
1. INTRODUCTION
Different types of powders, such as metallic, non-metallic, and polymeric particles, can be incorporated to form slurries in liquid mediums. These fully suspended fluids exhibit higher heat capacities compared to plain fluids, resulting in improved heat transfer efficiency within the heat exchanger. A mechanical application test was conducted to observe the impact of slurry mass, droplet size, scale, and flow rate on heat exchange behavior.
Heat exchangers demonstrate satisfactory thermal efficiency for efficient commercial operation of industrial machinery. To enhance the thermal efficiency of heat exchanger pipes through convection heat transfer, various strategies can be employed, both active and passive. These strategies encompass modifications to the fluid passage, incorporation of spin generators, and utilization of Nano fluids. The primary objectives of these methods are to reduce plant irreversibility, improve heat transfer efficiency, optimize volume, and enhance fluid flow characteristics.
While suspended particles typically have dimensions ranging from micrometers to millimeters, their large size can lead to issues such as scratching and blockage. To overcome these challenges, fluids with nanoparticles are utilized to achieve limited practical issues in heat exchange enhancement. Nanoparticles offer a promising approach for improving fluid heat exchange characteristics. Particles smaller than 100 nm exhibit unique properties distinct from those of ordinary solids. Nano-sized powders demonstrate enhanced interactions compared to micron-sized particles. Researchers have explored the suspension of nanoparticles in fluids to create highly effective heat exchange fluids.
Researchers worldwide have been investigating ways to enhance convective heat transfer efficiency in tubes by exploring different types of additives as liquid phase transformers. These additives contribute to changes in addition geometry, normal velocity gradients, and act as inducers of mixing, disorder swirl generators, and dwell time enhancers. The transfer of thermal energy occurs when the liquid passes from one fluid to another within the heat exchanger. Heat transmission can occur through the fluid surface or between solid-fluid particles. Thermal
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