Preferred Language
Articles
/
DxcPZpIBVTCNdQwCjq-R
Finite Time Disturbance Observer Based on Air Conditioning System Control Scheme
...Show More Authors

A novel robust finite time disturbance observer (RFTDO) based on an independent output-finite time composite control (FTCC) scheme is proposed for an air conditioning-system temperature and humidity regulation. The variable air volume (VAV) of the system is represented by two first-order mathematical models for the temperature and humidity dynamics. In the temperature loop dynamics, a RFTDO temperature (RFTDO-T) and an FTCC temperature (FTCC-T) are designed to estimate and reject the lumped disturbances of the temperature subsystem. In the humidity loop, a robust output of the FTCC humidity (FTCC-H) and RFTDO humidity (RFTDO-H) are also designed to estimate and reject the lumped disturbances of the humidity subsystem. Based on Lyapunov theory, the stability proof of the two closed-loop controllers and observers is presented. Comparative simulations are carried out to confirm that the proposed controller outperforms conventional methods and offers greater accuracy of temperature, humidity, and carbon dioxide concentration, having superior regulation performance in terms of a rapid finite time convergence, an outstanding disturbance rejection property, and better energy consumption. In addition to presenting the comparative simulation results from the control applications on the VAV system, the quantitative values are provided to further confirm the superiority of the proposed controller. In particular, the proposed method exhibits the shortest settling time of, respectively, 15 and 40 min to reach the expected temperature and humidity, whereas other comparative controllers require a longer time to settle down.

Scopus Clarivate Crossref
View Publication
Publication Date
Mon Nov 01 2021
Journal Name
Energy Reports
Global solar radiation prediction over North Dakota using air temperature: Development of novel hybrid intelligence model
...Show More Authors

View Publication
Scopus (80)
Crossref (82)
Scopus Clarivate Crossref
Publication Date
Sat Mar 30 2024
Journal Name
Al-qadisiyah Journal For Engineering Sciences
Investigation of an automobile air-conditioner with a liquid-suction heat exchanger using R134a and R1234yf
...Show More Authors

Air-conditioning systems (ACs) are essential in hot and humid climates to ensure acceptable ambient air quality as well as thermal comfort for buildings users. It is essential to improve refrigeration system performance without increasing the effects of global warming potential (GWP) and ozone depletion potential (ODP). The main objective of this study is to evaluate the performance of an air conditioning system that operates with a liquid suction heat exchanger (LSHX) through implementing refrigerants with zero OPD and low GWP (i.e., R134a and R1234yf). Liquid suction heat exchanger (LSHX) was added to an automobile air conditioning system (AACS).When Liquid suction heat exchanger was added to the cycle, primary results indicated t

... Show More
View Publication
Scopus (1)
Scopus Crossref
Publication Date
Sun Jan 30 2022
Journal Name
Heat Transfer
Theoretical and experimental investigation of a heat pipe heat exchanger for energy recovery of exhaust air
...Show More Authors

Heat pipes and two‐phase thermosyphon systems are passive heat transfer systems that employ a two‐phase cycle of a working fluid within a completely sealed system. Consequently, heat exchangers based on heat pipes have low thermal resistance and high effective thermal conductivity, which can reach up to the order of (105 W/(m K)). In energy recovery systems where the two streams should be unmixed, such as airconditioning systems of biological laboratories and operating rooms in hospitals, heat pipe heat exchangers (HPHEs) are recommended. In this study, an experimental and theoretical study was carried out on the thermal performance of an air‐to‐air HPHE filled with two refrigerants as working fluids, R22 and R407c. The heat pipe he

... Show More
Scopus (17)
Crossref (17)
Scopus Clarivate Crossref
Publication Date
Sat Mar 01 2025
Journal Name
Geoenergy Science And Engineering
Empirical model for predicting slug-pseudo slug and slug-churn transitions of upward air/water flow
...Show More Authors

A pseudo-slug flow is a type of intermittent flow characterized by short, frothy, chaotic slugs that have a structure velocity lower than the mixture velocity and are not fully formed. It is essential to accurately estimate the transition from conventional slug (SL) flow to pseudo-slug (PSL) flow, and from SL to churn (CH), by precisely predicting the pressure losses. Recent research has showed that PSL and CH flows comprise a significant portion of the conventional flow pattern maps. This is particularly true in wellbores and pipelines with highly deviated large-diameter gas-condensate wellbores and pipelines. Several theoretical and experimental works studied the behavior of PSL and CH flows; however, few models have been suggested to pre

... Show More
View Publication
Scopus (7)
Crossref (7)
Scopus Clarivate Crossref
Publication Date
Fri Jun 01 2012
Journal Name
Journal Of Economics And Administrative Sciences
The Probability of Implementation Some Rules of Process Organization –Study of the Production Air-cooler engines
...Show More Authors

This research is Interested in how the performance and implementation of factory production engine coolants of the General Company for Electrical Industries of its work, and to facilitate the flow of the decisions of senior management and access to all configurations, to ensure differentiation desired and reduce lost sales, resulting from poor scheduling of operations through the application of certain rules of scheduling operations in the production plant Engines Air-cooler, the objectives of research in identifying the best base and working to reduce the time and cost of Same Rules of Process which are considered the most influential of any organization and thr

... Show More
View Publication Preview PDF
Crossref
Publication Date
Tue Dec 31 2013
Journal Name
Al-khwarizmi Engineering Journal
The Power Enhancement of a Mini-Gas Turbine by Adding Ethanol to the Compressor Inlet Air
...Show More Authors

An experimental study is conducted on the utilization of the inlet ethanol injection technique in order to evaluate its impact on the performance of a two-shaft T200D mini-gas turbine engine. The maximum degradation recorded in power output was 32.8% at the climate temperature of 45oC. Nevertheless, at that temperature, adding ethanol with Eth/LPG ratio of 20% by volume brought an enhancement in power output of 19.2% compared to normal LPG run. SFC of the dual-fuel engine ranked a level of 22% higher than that with pure LPG consumption. The overall efficiency suffered a maximum reduction of 14.4% with Eth/LPG fuel ratio of 20%, but when the loading was raised beyond 70% of the engine full load; the efficiency of dual-fuel engi

... Show More
View Publication Preview PDF
Publication Date
Sat Jan 13 2024
Journal Name
Journal Of Advanced Research In Fluid Mechanics And Thermal Sciences
Influence of Surrounding Air Temperature and Humidity upon the Performance of a Gas Turbine Power Plant
...Show More Authors

Nowadays, energy demand continuously rises while energy stocks are dwindling. Using current resources more effectively is crucial for the world. A wide method to effectively utilize energy is to generate electricity using thermal gas turbines (GT). One of the most important problems that gas turbines suffer from is high ambient air temperature especially in summer. The current paper details the effects of ambient conditions on the performance of a gas turbine through energy audits taking into account the influence of ambient conditions on the specific heat capacity ( , isentropic exponent ( ) as well as the gas constant of air . A computer program was developed to examine the operation of a power plant at various ambient temperature

... Show More
View Publication
Scopus (4)
Crossref (2)
Scopus Crossref
Publication Date
Tue Feb 12 2019
Journal Name
Iraqi Journal Of Laser
Plasmonic Nanoparticles Decorated Salty Paper Based on SERS Platform for Diagnostic low-Level Contamination: Lab on Paper
...Show More Authors

In this research, a low cost, portable, disposable, environment friendly and an easy to use lab-on-paper platform sensor was made. The sensor was constructed using a mixture of Rhodamine-6G and gold nanoparticles also Sodium chloride salt. Drop–casting method was utilized as a technique to make a platform which is a commercial office paper. A substrate was characterized using Field Emission Scanning Electron Microscope, Fourier transform infrared spectroscopy, UV-visible spectrophotometer and Raman Spectrometer. Rh-6G Raman signal was enhanced based on Surface Enhanced Raman Spectroscopy technique utilized gold nanoparticles. High Enhancement factor of Plasmonic commercial office paper reaches up to 0.9 x105 because of local surface pl

... Show More
View Publication Preview PDF
Publication Date
Mon Aug 01 2022
Journal Name
Baghdad Science Journal
Influence of Cold Plasma on Sesame Paste and the Nano Sesame Paste Based on Co-occurrence Matrix
...Show More Authors

The aim of the research is to investigate the effect of cold plasma on the bacteria grown on texture of sesame paste in its normal particle and nano particle size. Starting by using the image segmentation process depending on the threshold method, it is used to get rid of the reflection of the glass slides on which the sesame samples are placed.  The classification process implemented to separate the sesame paste texture from normal and abnormal texture. The abnormal texture appears when the bacteria has been grown on the sesame paste after being left for two days in the air, unsupervised k-mean classification process used to classify the infected region, the normal region and the treated region. The bacteria treated with cold plasma, t

... Show More
View Publication Preview PDF
Scopus (13)
Crossref (7)
Scopus Clarivate Crossref
Publication Date
Tue Mar 01 2016
Journal Name
Journal Of Engineering
Design and Simulation of Sliding Mode Fuzzy Controller for Nonlinear System
...Show More Authors

Sliding Mode Controller (SMC) is a simple method and powerful technique to design a robust controller for nonlinear systems. It is an effective tool with acceptable performance. The major drawback is a classical Sliding Mode controller suffers from the chattering phenomenon which causes undesirable zigzag motion along the sliding surface. To overcome the snag of this classical approach, many methods were proposed and implemented. In this work, a Fuzzy controller was added to classical Sliding Mode controller in order to reduce the impact chattering problem. The new structure is called Sliding Mode Fuzzy controller (SMFC) which will also improve the properties and performance of the classical Sliding Mode control

... Show More
View Publication Preview PDF