Numerical investigation of heat transfer and fluid flow in tubes induced with twisted tape inserts

摘要: Heat energy is important to all aspects of life. Various industries including food processing plants, chemical thermal power refrigeration and air conditioning equipments, petrochemical etc. are faced with the problems effective utilization, conservation recovery heat. The production heat exchangers involves huge investments for capital operation costs. In view this, it has become design that will be efficient also save energy, cost materials. Different techniques known as transfer enhancement employed achieve this. Of these techniques, tube-insert technology applied in present research. No prior work on fluid flow a tube induced twisted tape insert emphasis cuts different geometrical shapes but equal area been reported. Hence, work, water tubes inserts different-shape-equal-area investigated numerically. The studies pay attention thermo-hydraulic characteristics laminar, transitional turbulent flows through designs fitted individually under uniform wall flux. numerical simulation this carried out by using Fluent software. RANS-based RNG κ-e model because found give more accurate result than other turbulence models. Since not fully turbulent, variant SST κ-ω flow. analyses quantify improvement transfer, friction factor performance index each systems results used ascertain system gives best performance. Correlations proposed Nusselt number factor. The indicates superior mixing provided alternate-axis triangular cut one reasons why offers higher those offered tubes. Interestingly, increases size width increase decreases pitch increases. affects start end transition Transition occurs ends earliest highest enhancement. Investigation performed combined forced free convection an inclined flows. at angles (15o≤θ≤90o ) respect horizontal. Importantly, mixed convection, inclination angle