Continuum mechanics deals with physical properties of e.g. fluids which are independent of any particular coordinate system in which they are observed. These physical properties are then represented by tensors, which are mathematical objects that have the required property of being independent of a specific coordinate system.

Dating back to prehistoric times, humankind has sought ways to maintain food and drink at lower than ambient temperatures, culminating the vibrant and dynamic HVAC&R industry that we see today.  Learn more about the history in this brief summary

Pure water freezes at 0 °C, that is, the polar water molecules arrange themselves into ice crystals.  To be able to use the good heat transfer properties of water at lower temperatures, and to derive additional benefits that can be found with certain additives, we consider the properties of glycol

As a part of the EU, the UK was subject to the terms and conditions of legislation governing the emissions and supply of fluorinated greenhouse gases in Europe. With effect from 1st January 2021 however, these regulations will no longer apply in Great Britain and will be replaced.

In HVAC applications such as chillers or air conditioning systems, fans are second only to compressors in being consumers of power.  There are a few different options available for fan motors and EC fans can have a big impact on the energy efficiency of the unit, as well as the levels of noise generated and maintenance required

Until relatively recently, the energy efficiency of chillers has mostly been indicated by manufacturers by stationary maps at full load operating points or the EER, the Energy Efficiency Ratio, which only represents a fraction of the real operating behaviour during the course of the year

Correctly sizing a chiller is of critical importance to ensure that it can meet the anticipated cooling load.  One should also be careful not to oversize a chiller as this impacts not only the capital cost, but also incurs unnecessary whole-life costs.  In this article we look at what information is required in order to properly select the right chiller for the job.

The ozone layer is one layer of the stratosphere and the stratosphere is the second layer of the Earth’s atmosphere.  This is of importance to our industry as some chemicals that were historically used in the refrigeration process have been found to deplete the Earth’s protective ozone layer

We find HVAC systems in buildings and industrial processes frequently these days.  Such systems move air around a particular space and the technical term for this is air handling unit.  In this feature we consider the construction of AHU’s, and the options available for the sections that it is most commonly consists of

In a departure from our usual message to the industry, in May’s edition of the ACR News we shared some researched information about how to mitigate the spread of viruses in buildings by use of mechanical measures.  As an industry we believe that we have a responsibility to promote best practice in this regard

In order to understand the acoustics of any installation, it’s important to understand how sound is perceived and calculated.  In Part 1 of a three part series, we look at the mathematics and physics of sound so that we can reach that understanding