Batch reverse osmosis (BRO) systems may enable a significant reduction in energy consumption for desalination and water reuse. BRO systems operate with variable pressure, by applying only slightly more pressure than is needed to overcome the osmotic pressure and produce reverse water flux. This study explains, quantifies, and optimizes the energy-saving performance of realistic batch designs im...

Tools for fitting low-complexity nonlinear models based on experimental data are examined through the example problem of finding a reduced-order model suitable for control of a combustion instability operating in a limit cycle. This proceeds in four parts; physical modeling, linear system identification, nonlinear analysis, and validation test design. It is shown how the nonlinear tools of desc...

Wide-range level shifters play critical roles in ultra-low-voltage circuits and systems. Although state-of-the-art level shifters can convert a sub threshold voltage to the standard supply voltage, they may have limited operating ranges, which restrict the flexibility of dynamic voltage scaling. Therefore, this paper presents a novel level shifter, of which the operating range is from a deep su...

The fact that distillation columns, even in the ideal binary case, may display multiple steady states and unstable operating points has only recently been recognized. This article addresses some implications of these phenomena for the operation and control of distillation columns. Under manual operation, the multiplicity and instability will result in inability to reach separations correspondin...

In this article we introduce a novel operating principle for a temperature modulated electronic nose. The aim is to perform gas discrimination with metal oxide gas sensors in natural, uncontrolled environments where the sensor is exposed to patches of gas only for short periods of time. The proposed Parallelized Temperature Modulated e-nose (PTM e-nose) allows to speed-up discrimination of gase...

A regenerative organic Rankine cycle (RORC) is modeled and optimized for the use of waste heat recovery from a prime mover (PM). Three PMs including, a diesel engine, a gas engine, and a microturbine are selected in this study. Four refrigerants including isobutane, R123, R134a, and R245fa are selected. The nominal capacity of the PM, PM operating partial load, turbine inlet pressure, condenser...

In development of Homogeneous Charge Compression Ignition (HCCI) engines, simultaneous control of combustion phasing and power output has been a major challenge. In this study, a new strategy is developed to control the engine power output and combustion phasing at any desired operating condition. A single zone thermodynamic model coupled to a full kinetic mechanism of Primary Reference Fuels (...

An integrated solar combined cycle (ISCC) is analyzed at "off-design" operating conditions. Using the principles of thermodynamics heat and mass transfer a computer code is developed in FORTRAN programming language to simulate the system’s hourly performance under steady state conditions. Three scenarios are considered for the study. In the first one, only the combined cycle (CC) is studied. In...

In this work, a novel dual-nozzle ejector enhanced triple-evaporator refrigeration cycle (DETRC) without separator is proposed to improve the performance of the conventional ejector one (CETRC). The performance of DETRC is analyzed and compared with CETRC in term of energy coefficient of performance (COPen). Under given operating conditions, the COPen improvement of the no...

This paper introduces the dual-mode refrigeration system for ice storage air conditioning. A computational model relating to the exergy loss amount and loss rate is developed in each component of the refrigeration cycle loop. A case study is presented to demonstrate the applicability of the model developed. Exergy analysis results of the refrigeration system in ice storage operating mode are co...