Isotherm Ultra Low Charge “SX” Evaporator was installed at a rink facility in British Columbia in 2019 to replace a conventional flooded evaporator. After installation, it was confirmed that the new “SX” Chiller required only 50 lbs. of ammonia, while the 15-year-old flooded chiller that was removed held approximately 1500 lbs. of ammonia. The “SX” […]
Does Annular Flow Boiling Inside a Tube improve Heat Exchanger Performance? Vast literature is available about two-phase flow boiling in horizontal round tubes in heat exchangers. Several studies on flow pattern and mapping are also available. However, limited literature is available about two-phase flow in small cylindrical annular passages. A detailed experimental study was conducted […]
Why does Carbon Dioxide (CO2) stand out in a DX Heat Exchanger in low temperature systems? Since the Kigali Amendment of Montreal Protocol in 2016, the world refrigeration community has been looking more into the natural refrigerant route. The Kigali Amendment calls for the phase out of Hydrofluorocarbons (HFC) as follows: Developed countries: 10% reduction […]
An Important Consideration in Designing a Heat Exchanger operating close to Freeze Point of a fluid – Phenomenon of “Freeze Fouling”
An Important Consideration in Designing a Heat Exchanger operating close to Freeze Point of a fluid – Phenomenon of “Freeze Fouling” This type of fouling can occur at a surface when a medium is cooled to within the vicinity of its freeze point. It is a good engineering practice to design a heat exchanger by […]
Next Generation Power Plants: Supercritical Carbon Dioxide When Carbon Dioxide (CO2) operates above its critical point, it is called Supercritical Carbon Dioxide (sCO2) where there is no distinction between liquid and gas phase. In this phase CO2 undergoes a continuous, non-isothermal transition from “gas-like” to “liquid-like” properties resulting in significant spikes in specific heat and […]
Does two identical twisted tape inserts each with opposite twist result in a different thermal hydraulic performance?
Does two identical twisted tape inserts each with opposite twist result in a different thermal hydraulic performance? Detailed single phase heat transfer and pressure drop tests were conducted in a tube with two types of twisted tapes as shown in Figure 1. A twist ratio (L/D) is defined as the ratio of twist pitch at […]