Transient laminar mixed convection in an asymmetrically and differentially heated vertical channel of finite length subject to an opposing buoyancy is investigated by solving the unsteady two-dimensional Navier–Stokes and energy equations. Results illustrate the effects of buoyancy strength or Richardson number Ri 1⁄4 Gr=Re and Reynolds number Re on the overall flow structure and the nondimensi...

In this paper, a modified two-fluid model has been adopted to simulate the process of upward vertical subcooled flow boiling of refrigerant R-113 in a vertical annular channel at low pressure. The modified model considers temperature dependent properties and saturation temperature variation and was validated against a number of published low-pressure subcooled boiling experiments. The results s...

To improve the currently available multi-segment lumped parameter models, a new dynamic mathematic model for single-phase heated tubes is established by employing equations instead of traditional static calculating heat transfer across control volume’s tube wall. Through separating temporal and spatial terms partial differential equations, combining both analytical methods, an solution temperat...

Alfamart is a minimarket in which there service to consumers, therefore services must be considered and taken into account for consumer convenience. The purpose of this study see how optimal the at branch Perum Cengkong. Cengkong uses Single Channel-Single Phase queuing system. results were that by testing normality data using Statistical Program Social Science (SPSS) software, 1-Sample Kolmogo...

The simplest water diversion method in irrigation systems is using intakes. Measuring the mean velocity is one of the essential hydraulic parameters in increasing the efficiency of the intake. In this study, the mean velocity was predicted for different width ratios of an intake using ANN-MLP neural network model. In order to do that, the flow field within a 90-degree intake was first simulated...

the world is facing severe challenges in meeting the rapidly growing demand for water resources. in addition,irrigation water which is the largest use of water in most developing countries and arid and semi arid regions, will likelyhave to be diverted increasingly to meet the needs of the households in urban areas and industry sectors whilst remaining aprime engine of agricultural growth. a lin...