Is Shell and Plate Heat Exchanger a better choice for Ammonia/Carbon Dioxide Condenser? There is no ideal product for a certain application. Each product type has its pros and cons; however, as engineers it is our job to select suitable equipment with close attention to risk analysis. In the case of Ammonia/Carbon Dioxide Condenser, besides […]
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 […]
Why does a scratched surface act better boiling surface in a Heat Exchanger as compared to a smooth surface?
Why does a scratched surface act better boiling surface in a Heat Exchanger as compared to a smooth surface? The first detailed boiling study was conducted by Nukiyama in 1934 when he plotted the boiling curve showing the relationship between heat and temperature. The curve is known as the Nukiyama boiling curve. Figure 1 shows […]
Shell Side Direct Expansion Evaporation (SX) of Ammonia on a 3-D structured surface Tube Bundle with exit superheat effect
Shell side direct expansion evaporation (SX) of ammonia on a 3-D structured surface tube bundle with exit superheat effect Ammonia is an environmentally safe and low-cost natural refrigerant which has been in use for more than a century. The Kigali amendment phase-out of HFCs has further strengthened the case for ammonia. The limitations of ammonia […]
A Shell and Tube Vertical Heat Exchanger (Chiller) have been developed that has smaller footprint than a Plate and Frame Heat Exchanger. The idea behind it is to force the boiling refrigerant such as Ammonia, Carbon Dioxide or any other refrigerant to a thin boiling regime thus resulting in higher heat transfer. The Chiller does […]