To give you an idea of how a centrifugal chiller should be designed and what you can expect from our design services, let us first start by knowing its basic refrigeration cycle. Basically, a centrifugal chiller makes use of the vapor compression cycle as a means of chilling water. It then rejects the heat it has gathered from the chilled water along with the heat gathered from the compressor to the water loop which is cooled by a cooling tower.
A centrifugal chiller normally contains four different components which are described below:
The evaporator is responsible for removing heat from the chilled water, lowering its temperature as a result. The removed heat is then used for boiling the refrigerant and changing it from liquid to gas.
The compressor consists of a centrifugal compressor and a prime mover. The centrifugal compressor works pretty much like a centrifugal water pump by raising the temperature and pressure of the refrigerant, a process achieved through the conversion of kinetic energy to pressure.
The condenser is the complete opposite of evaporator in the sense that it condenses refrigerant from gas to liquid. However, just like the evaporator, it’s also often a shell and tube heat exchanger. Basically, heat raises the cooling water’s temperature, likewise known as condenser water. Afterward, it then carries heat to the cooling tower where it gets rejected outside.
Once the refrigerant is in its liquid form, it will then go through an expansion device whose task is to reduce pressure. It can be a simple system made of an orifice plate or a complex one such as an electronic modulating expansion valve.
Some high-performance centrifugal chillers use either an electronic modulating expansion valve or a thermal expansion valve for excellent modulation alongside a wide range of temperature conditions and capacity. Here at NYE, we make sure that all of the above components are taken into consideration. Efficiency, accuracy, and attention to detail are what we promise.
Features of a Highly Efficient Chiller Design
To make sure we can create centrifugal chiller designs that are centered around high efficiency not just in terms of performance but also in overall electrical costs, we have to make sure that the following features are put in place:
A significantly lightweight and compact centrifugal chiller design allows you to save a lot of space in your facility. Aside from that, it also makes transport and replacement a lot easier. By attaching downsized components, such as the economizer, we are able to achieve a highly compact but fully functional and highly-efficient chiller. Also, the fact that it’s modular means you can transport parts of the chiller separately even across tight spaces.
Our designs also feature a two-stage compressing cycle which dramatically improves a chiller’s overall energy efficiency. It can also significantly reduce overall operational costs compared to the previous one-stage system. Lastly, this design is geared toward environmental conservation by reducing CO2 emission.
- Easy and Optimized Modular Installation
A modular design doesn’t just let you transport each module of your centrifugal chiller separately. It also makes for an easier and quicker installation. You can control module-by-module operation by means of several combination options. As a result, you can maximize partial load efficiency. Moreover, the presence of various installation options means you can customize the installation in accordance with your space and cooling demands.
- Optimized Central Control
We also make sure that our designs feature optimized central control. This allows you to use various control solutions to monitor your entire cooling system with ease. Aside from that, it also lets you control and manage your system anytime and anywhere you want.
- Improved Partial Load Efficiency
Our design incorporates precision control which can significantly improve the partial load efficiency of your centrifugal chiller. This results in a 54% increase in overall partial load efficiency compared to other two-stage models which run at a fixed speed. As a result, you can enjoy even more savings on your electrical costs.
By simplifying the compressor’s structure, we are able to reduce noise from our chiller designs by up to 74 dB. This makes them applicable for use in areas that require low noise and vibration.
- Oil-Free Piping Structure
Other than the traditional centrifugal chiller system, we also create designs for oil-free chillers. Compared to traditional chillers, an oil-free system has a simplified piping structure which is made possible by getting rid of any oil-related parts. This means that it’s no longer necessary to replace oil or filters, allowing you to save more time and money.
- Magnetic and Air Bearing Technologies
The magnetic bearing technology can significantly improve a chiller’s energy efficiency and overall lubrication loss. The air bearing technology, on the other hand, reduces friction loss along with improved overall efficiency. As it’s such an advanced technology, it's often used in aircraft applications and other industries.