scholarly journals Analysis of Common Problems of Noise and Vibration in Building Heating Ventilation Air Conditioning Design

2021 ◽  
Vol 283 ◽  
pp. 01051
Author(s):  
Xiaolong Ruan ◽  
Yisong Yin
Keyword(s):  
Continuous Improvement ◽  
Air Conditioning ◽  
Preventive Measures ◽  
Hvac System ◽  
Continuous Growth ◽  
Noise And Vibration ◽  
Vibration Problems ◽  
Common Problems ◽  
Air Conditioning Systems ◽  
And Control

With the continuous growth of my country's economy and the continuous improvement of the people's economic level, the demand for the design of heating, ventilation and air conditioning systems has also increased. The HVAC system is very important in the building environment. When optimizing the relevant design, it is necessary to always consider the design details of the HVAC system and adjust the integrity of the design, especially to take preventive measures in areas where noise and vibration may occur to avoid heating serious problems caused by noise and general vibration when the communication system is running. This article outlines how to avoid and control common noise and vibration problems when designing HVAC projects.

scholarly journals A Multi-Timescale Bilinear Model for Optimization and Control of HVAC Systems with Consistency

Energies ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 400 ◽  
Author(s):  
Zelin Nie ◽  
Feng Gao ◽  
Chao-Bo Yan
Keyword(s):  
Optimization Model ◽  
Air Conditioning ◽  
State Of The Art ◽  
Hvac Systems ◽  
Practical Significance ◽  
Hvac System ◽  
Bilinear Model ◽  
Optimization And Control ◽  
And Control ◽  
Slow Timescale

Reducing the energy consumption of the heating, ventilation, and air conditioning (HVAC) systems while ensuring users’ comfort is of both academic and practical significance. However, the-state-of-the-art of the optimization model of the HVAC system is that either the thermal dynamic model is simplified as a linear model, or the optimization model of the HVAC system is single-timescale, which leads to heavy computation burden. To balance the practicality and the overhead of computation, in this paper, a multi-timescale bilinear model of HVAC systems is proposed. To guarantee the consistency of models in different timescales, the fast timescale model is built first with a bilinear form, and then the slow timescale model is induced from the fast one, specifically, with a bilinear-like form. After a simplified replacement made for the bilinear-like part, this problem can be solved by a convexification method. Extensive numerical experiments have been conducted to validate the effectiveness of this model.

scholarly journals Fault Detection and Diagnosis of Air Handling Unit: A Review

2019 ◽  
Vol 255 ◽  
pp. 06001 ◽  
Author(s):  
Cheng Yew Leong
Keyword(s):  
Fault Detection ◽  
Air Conditioning ◽  
Early Stage ◽  
Fault Detection And Diagnosis ◽  
Commercial Building ◽  
Air Handling Unit ◽  
Operations And Maintenance ◽  
Detection And Diagnosis ◽  
Air Conditioning Systems ◽  
And Control

Air-conditioning systems consumed the most energy usage nearly 45% of the total energy used in commercial-building. Where AHU is one of the most extensively operated equipment and this device is typical customize and complex which can results in hardwire failure and controller errors. The efficiency of the system is very much depending on the proper functioning of sensors. Faults arising from the sensors and control systems are a major contribution to the energy wastage. As such faults often go unnoticed for extended periods of time until the deterioration in performance becomes great enough to trigger comfort complaints or total equipment failure. Energy could be reduced if those faults can be detected and identified at early stage. This paper aims to review of various existing automated fault detection and diagnosis (AFDD) methods for an Air Handling Unit. The background of AHU system, general fault detection and diagnosis framework and typical faults in AHU is described. Comparison and evaluation of the various methodologies will be reviewed in this paper. This comparative study also reveals the strengths and weaknesses of the different approaches. The important role of fault diagnosis in the broader context of air- conditioning is also outlined. By identifying and diagnosing faults to be repaired, these techniques can benefits building owners by reducing energy consumption, improving indoor air quality and operations and maintenance.

scholarly journals Application of soft sensor technology in HVAC system test

2021 ◽  
Vol 261 ◽  
pp. 01013
Author(s):  
Changbao Guo
Keyword(s):  
Air Conditioning ◽  
Rapid Development ◽  
Sensor Technology ◽  
Measurement Technology ◽  
Hvac System ◽  
Air Conditioning System ◽  
Test Parameters ◽  
Soft Measurement ◽  
And Control ◽  
Measurement And Control

With the rapid development of modern society, the measurement and control requirements of key variables of air conditioning test technology are also increasing. When the parameters of HVAC system are measured and controlled, there are a large number of sensors and instruments used. When sensor failure or measurement error distortion occurs, the air conditioning system cannot operate normally and automatically. At the same time, some variables in the test parameters cannot be directly collected by the sensor. In order to solve these problems, researchers have focused on soft measurement technology in recent years, which provides a good breakthrough for the measurement and control of air conditioning system test parameters. This paper expounds the application of soft measurement technology in HVAC system.

An Innovation-Based Methodology for HVAC System Fault Detection

1985 ◽  
Vol 107 (4) ◽  
pp. 284-289 ◽  
Author(s):  
P. B. Usoro ◽  
I. C. Schick ◽  
S. Negahdaripour
Keyword(s):  
Mathematical Model ◽  
Control Systems ◽  
Energy Management ◽  
Air Conditioning ◽  
Energy Use ◽  
Hvac System ◽  
Test Results ◽  
Nonlinear Mathematical Model ◽  
Control Scheme ◽  
And Control

Although Energy Management and Control Systems (EMCS) have since the early 1970’s contributed significantly to the reduction (20-40 percent) of energy use in buildings without sacrificing occupants’ comfort, their full capabilities have not been completely realized. This is in part due to their inability to quickly detect and compensate for failures in the Heating, Ventilation and Air Conditioning (HVAC) system. In fact, no matter how good the control scheme for the HVAC system might be, the presence of undetected faults can completely offset any expected savings. This paper presents a methodology for detecting faults in an HVAC system using a nonlinear mathematical model and an extended Kalman filter. The technique was implemented in a computer program and successfully used to detect “planted” faults in simulations of the air handler unit of an HVAC system. Test results are presented to demonstrate the effectiveness of the methodology.

Nonlinear Control of an Air Handling Unit Using Feedback Linearization

2009 ◽  
Author(s):  
Hamed Moradi ◽  
Majid Saffar-Avval
Keyword(s):  
Air Conditioning ◽  
Feedback Linearization ◽  
Hvac Systems ◽  
Pi Controller ◽  
Hvac System ◽  
Flow Rates ◽  
Air Handling Unit ◽  
Transfer Rules ◽  
And Control ◽  
Dynamic Variables

Heating, ventilation and air conditioning (HVAC) systems are equipments used to maintain satisfactory comfort conditions in buildings. Also, energy consumption of ventilated buildings highly depend on the design, performance and control of HVAC systems. In this paper, nonlinear model of a multi-variable HVAC system is considered in which the control inputs are the air and cool water flow rates. Using thermodynamics and heat transfer rules, differential and consequently state space equations of the system are represented. To achieve a good performance, dynamic variables such as output temperature and relative humidity must be controlled. Using input-output feedback linearization, a PI controller is designed. It is shown that by applying the controller, system tracks from one operating point to another with an appropriate specification of time response. In addition, using feedback linearization guarantees robustness of the system against the parametric uncertainties associated with dynamic model.

scholarly journals Comparative Analysis of Energy Consumption, Indoor Thermal–Hygrometric Conditions, and Air Quality for HVAC, LDAC, and RDAC Systems Used in Operating Rooms

2020 ◽  
Vol 10 (11) ◽  
pp. 3721
Author(s):  
Tsung-Yi Chien ◽  
Ching-Chieh Liang ◽  
Feng-Jen Wu ◽  
Chi-Tsung Chen ◽  
Ting-Hsin Pan ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Air Quality ◽  
Air Conditioning ◽  
Operating Rooms ◽  
Conventional Heating ◽  
Hvac System ◽  
Total Energy Consumption ◽  
System A ◽  
Air Conditioning Systems ◽  
Daily Total

As controlling temperature and humidity is crucial for maintaining comfort and preventing microbial growth, operating rooms (ORs) are the most energy-intensive areas in hospitals. We aimed to evaluate the energy consumption of three dehumidification air conditioning systems used in ORs and their corresponding air quality for ORs at rest. This study selected three ORs using a conventional heating, ventilation, and air conditioning (HVAC) system; a liquid desiccant air conditioning (LDAC) system; and a rotary desiccant air conditioning (RDAC) system, respectively. The indoor thermal–hygrometric conditions, air quality, and energy consumption of the ORs were monitored in this study. The median levels of relative humidity (RH) were 66.7% in the OR using the conventional HVAC system, 60.8% in the OR using the LDAC system, and 60.5% in the OR using the RDAC system. The median daily total energy consumption of the RDAC system (10.1 kWh/m2) and LDAC system (11.8 kWh/m2) were 28.12% and 16.54% lower, respectively, than that of the conventional HVAC system (14.1 kWh/m2). The PM≥0.5 levels and airborne bacterial concentrations in the ORs met the ISO 14644-1 Class 7 standard and China’s GB50333-2013 standard, respectively. The RDAC system was clearly superior to the LDAC and conventional HVAC systems in terms of energy consumption.

Sign in / Sign up

Export Citation Format

Share Document