In this paper, we report direct calculations of cavitating pipe flows by the method of Space-Time Conservation Element and Solution Element, or the CE/SE method for short. The tenet of the CE/SE method is treating space and time as one entity, and the calculation of flow properties is based on the local and global space-time flux conservation. As a contrast to the modern upwind schemes, no Riemann solver is used, thus the logic of the present scheme for cavitating flows is much simpler. Two numerical examples are reported in this paper: (1) a hydraulic shock problem, and (2) a cavitating pipe flow. For the hydraulic shock problem, we demonstrate the capability of the CE/SE method for capturing contact discontinuities in cavitating fluids. For the pipe flows, a two-phase homogeneous equilibrium cavitation model is employed. In both cases, numerical results compared favorably with the experimental data and analytical solution.

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This paper reports one-and two-dimensional simulations of cavitating flows by the Space-Time Conservation Element and Solution Element (CE/SE) method. A continuum cavitation model based on specifying the speed of sound of two-phase flows is employed. The CE/SE method is a viable CFD method for flows at wide range of Mach numbers. The method is explicit and is suitable for time accurate simulations. Moreover, without using a Riemann solver or a reconstruction procedure, the logic and operation count is simple and efficient for sharp resolution of evolving liquid/vapor interfaces. To validate the present model, three cavitating flows are simulated: the one-dimensional simulation of the waterhammer effect, flows over a hydrofoil, and flows through a high-pressure fuel injector. Numerical results show salient features of cavitations commonly observed in experiments, including, reentrant jet, hydraulic flip, and cyclical cavitations. The numerical results compare favorably with previously reported data.

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The purpose of electrical load management in a manufacturing plant is to change the load profile in order to gain from reduced total system peak load and increased power factor. One of the widely taken approaches is to optimize the schedule of electrical equipment operation hours to take advantage of incentives and favorable pricing offered by utilities. In this paper, we present our work in designing and developing a web based tool for manufacturing plants to find out an optimal operation schedule of equipment so as to reduce energy cost. The tool allows users to configure their load by specifying electrical devices and their various parameters. Then the online system will assess power consumption over a certain time period, as well as peak power demand and power factor of the defined load.