Journal of Engineering Advancements

Numerical Analysis of Laminar Natural Convection Inside Enclosed Squared and Trapezoidal Cavities at Different Inclination Angles

2024-01-19T14:10:25+00:00

The effects of cavity shape by inclination angle on laminar natural convection inside trapezoidal and square-shaped cavities have been numerically investigated in this work. Several simulations had been conducted for various inclinations of the trapezoidal cavity at Rayleigh numbers (Ra) =10⁵ to 10⁶ in a laminar flow regime. The walls at the left and right sides of the cavities were heated isothermally, while the walls at the top and bottom sides were adiabatic. The problem was assumed to be 2-D and solved using the software package ANSYS Fluent 16.2. Cavity filled with air is examined in two distinct instances; varying boundary layers and the flow generated for the natural convection. This numerical study analyzed the flow characteristics, temperature distribution, and Nusselt number. The analysis reveals that as the Rayleigh number increases, the Nusselt number also increases, with a more pronounced effect at higher Rayleigh numbers. It has been observed that there is a substantial effect of cavity shapes on the Nusselt number. The presence of an angled wall inhibits convection resulting in stronger flow in the squared cavity compared to the trapezoidal cavity. From numerical results, it is also found that the temperature distribution at Ra = 10⁵ is wider than the temperature distribution at Ra= 10⁶.

Performance of Ceramic Tiles Waste as a Partial Replacement of Brick Aggregate on Mechanical and Durability Properties of Concrete

2024-02-21T03:45:07+00:00

The availability of natural aggregates such as stone chips is a particularly challenging issue nowadays. Ceramic materials are increasingly being used in new projects such as tiles, sanitary fittings, electrical insulators, and so on, due to ceramic’s fragile properties, which often break during production, shipping, and installation. So, ceramic waste is one of these materials that are probably cost-efficient to use as a substitution (0%, 25%, 50%, and 75%) for brick chips. This research examined the mechanical strength properties of ceramic tile waste (CTW) concrete, including its compressive strength and splitting tensile strength, and utilized a water absorption test to assess its durability and performance. This research used a mix ratio of 1:1.5:3 with a constant water-cement ratio (w/c) of 0.45, and a water-reducing superplasticizer named Conplast SP337 was used. For the mechanical and durability tests, a total of seventy-two (72) concrete cylinders of 100 mm × 200 mm were cast, cured, and tested at 7, and 28 days. Mechanical strength results revealed a significant increase of around 16.71% for 50% CTW concrete mixtures at the place of brick aggregates, and the water absorption performance improved with the incorporation of CTW in concrete mixes.

Heat Transfer Mechanism over a Trapezium-Shaped Device Including Heat Conductive Solid Circular Metal Block

2024-03-10T09:19:41+00:00

Combined convective flow design and heat transfer efficiency are investigated in this research for variation of some pertinent parameters inside a trapezoidal device along with heat conductive solid circular block. By the implementation of the Finite element method, flow, and heat transfer behavior are presented in detail for the ranges of Reynolds number, 50 ≤ Re ≤ 200, and Hartmann number, 20 ≤ Ha ≤ 150 along with mixed convection parameter Ri = 1. Obtained results for the flow and temperature field in the considered domain are shown in terms of the streamlines and isotherms. In addition, the heat transfer rate at the bottom heated and ceiling cold wall is presented by Nu_av_. A noteworthy heat transfer augmentation is found at both heated and cold surfaces due to upper values of Re. Interestingly, the better cooling efficiency of the device is marked out for the hot wall.

Improvement of the Nearest Neighbor Heuristic Search Algorithm for Traveling Salesman Problem

2024-03-30T06:13:01+00:00

The Traveling Salesman Problem (TSP) is classified as a non-deterministic polynomial (NP) hard problem, which has found widespread application in several scientific and technological domains. Due to its NP-hard nature, it is very hard to solve effectively and efficiently. Despite this rationale, a multitude of optimization approaches have been proposed and developed by scientists and researchers during the last several decades. Among these several algorithms, heuristic approaches are deemed appropriate for addressing this intricate issue. One of the simplest and most easily implementable heuristic algorithms for TSP is the nearest neighbor algorithm (NNA). However, its solution quality suffers owing to randomness in the optimization process. To address this issue, this study proposes a deterministic NNA for solving symmetric TSP. It is an improved version of NNA, which starts with the shortest edge consisting of two cities and then repeatedly includes the closest city on the route until an effective route is established. The simulation is conducted on 20 benchmark symmetric TSP datasets obtained from TSPLIB. The simulation results provide evidence that the improved NNA outperforms the basic NNA throughout most of the datasets in terms of solution quality as well as computational time.