Analysis of the HVAC Control and Protection Sensors for the Water Cooler Bus Stop Station (Dissertation Sample)

Analysis of the HVAC Control and Protection Sensors for the Water Cooler Bus Stop Station
Ahmed Daliaq
Institution
Analysis of the HVAC Control and Protection Sensors for the Water Cooler Bus Stop Station
Chapter 1: Introduction
The largest land area of Egypt is engulfed by the western desert. Drake, Breeze & Parker, (2013) estimates that approximately 700,000 squad kilometers (two-thirds of the country) of the dry land of Egypt is covered by desert. In some days, the temperatures can rise to 45-degree centigrade. In crowded places like bus stops, high temperatures can make people uncomfortable and cause anxiety. This condition calls for the deed to have modern bus stops in Egypt, with working and efficient Heating, ventilation, and air conditioning (HVAC) systems. The HVAC is an efficient way of making rooms with relatively high temperatures and poor air circulation comfortable for occupants.
However, despite their comfort benefits and improved health conditions, HVAC in passengers’ cabins and bus stations has been criticized for increased energy consumption. According to Göhlich, Kunith & Jefferies, (2015), HVAC installation in bus stations does not only increase energy consumption grid, but also increase the overall cost of running buses in the cities. Some sources also cities lack automation and well-improved sensors for the high-power consumption and lack of efficiency.
In response to several downfalls, HVAC has seen some improvements in the last two decades. One of the latest developments in HVAC is the inclusion of the control and protection sensors for water coolers. Digital sensors in HVAC were developed to create automation and to reduce the amount of power consumption by the refrigerators or air conditioners. As revealed by most statistical studies, refrigerators and air conditioners consume up to 17 percent of the total power consumed in the developing countries. In Taiwan, for example, energy consumed by households through air conditioners and refrigerators can increase up to 38 billion kilowatt hour (KWh) per year (Kernkamp, Linder & Kersten, 2002). The energy loss can be reduced by controlling the refrigeration cycle.
Control in Refrigerating Cycle of a Fridge/Air Condition and its Relationship with Energy Saving
The use of air conditioners and refrigerators has increased tremendously in the last ten years. According to the most survey, the improved quality of life and economic independence across the planet has pushed people to seek a more comfortable life. The increase in the number of users of ACs and refrigerators has resulted in a corresponding increase in energy consumption. This increase in energy consumption calls for urgent measures to be taken to conserve energy and to avoid wastages.
Several methods such as the development of new energy-efficient equipment, using green energy like solar power, and apply complex control strategies have been adopted to save energy in fridges/ACs. According to Cheng & Lee, (2014), the best method of saving energy in ACs and Fridges is the use of complex control strategies, because of its efficiency and relatively low cost of implementation. A research study conducted by Ma & Wang, (2009) on energy-efficient control strategies confirmed that energy consumption could be lowered significantly by using control strategies. For example, in AC, the feedback controller was developed to control the speed of pumps I central AC and consequently reduce the rate of energy consumption.
Moreover, Zhao et al. conducted a study on how temperature and humidity independent control strategy can be used to reduce energy consumption in AC. The result of the study confirmed that the strategy could be used to improve the performance of AC and create a comfortable room environment even in hot and humid conditions. A fuzzy logic control strategy can also be used in multi-unit ACs to enhance energy efficiency.
The development of ACs and fridges has been driven by the need to achieve high efficiency, lowest energy consumption rate, more technologically advanced and excellent human comfort. In the early 1990s, the window type ACs were modified to split type to reduce noise by keeping the compressor outdoor. The growing demand for energy and the perpetual campaign on reduced energy consumption in the 2000s has led to the modification of the AC compressors from fixed frequency to convertible. The initial model with the fixed frequency control of compressor consumed too much power due to temperature variation during on-off output. On the other hand, the convertible frequency control system uses an electronic expansion valve to control the compressor output and to continuously regulate the rate of flow of refrigerant depending on the indoor thermal mass for energy conservation.
Control in Refrigerating Cycle of a Fridge/Air Condition and its Relationship with Protection
The primary control in the refrigerating cycle in AC that ensures its protection and longer life span is ensuring the refrigerant used in the system is of the right quality. One of the major causes of damage to the compressor is the use of inappropriate refrigerant liquid in the compressor. In most cases, the best compressor is made of a vapor moving pump the allows an easy form of refrigerant liquid. The compressor should also contain the maximum amount of refrigeration liquid. However, an increase in the volume of refrigerant would mean that various components would change. For example, size, weight, efficiency, noise and most importantly the cost may increase or decrease depending on the amount of addition of the refrigerant liquid.
Liquid refrigerants can be associated with several problems in an AC. The first problem is the refrigerant migration that occurs when refrigerant accumulates in the compressor when the compressor is no operating. Refrigerant migration can occur due to the pressure difference caused a difference in temperature of the compressor and that of the evaporator. In most case, this migration happens in winter, when the temperatures fall. The other problem is the liquid refrigerant slugging. Liquid slugging is caused by the passage of the refrigerant through the discharge valve. Liquid slugging can cause several damages such as blown head gaskets, broken valves, and broken connecting rods. These damages can jeopardize the overall lifespan of the AC or refrigerator.
Reading and Monitoring the Cycle or Refrigeration or Cooling
Monitoring of the AC involves some stages. First, is to configure temperature sensors to measure evaporators input air temperature. Secondly, to measure the output-air temperature form the same operator. The sensors are also configured to measure both to calculate the performance rate of the said evaporator and to sense if the air in the said evaporator.
HVAC consume a relatively high amount of electricity. If the system is not working efficiently, then there are high chances that the water may be contaminated. It is therefore important to ensure that the system works efficiently and so that every penny invested in the