Comfortable, efficient, and affordable heating, ventilation, and air conditioning systems in buildings are highly desirable due to the demands of energy efficiency and environmental friendliness. Traditional vapor-compression air conditioners exhibit a lower coefficient of performance (COP) (typically 2.8-3.8) owing to the cooling-based dehumidification methods that handle both sensible and lat...

The classical substances as Hydrochlorofluorocarbons (HCFCs) used as working fluids in the vapour compression plants have to be replaced by new substances because of their ozone depletion potential and their greenhouse effect. Carbon dioxide (CO2) is non-toxic, non-flammable, has zero ozone depletion potential and negligible global warming potential as refrigerant. Referring to a transcritical ...

Title of Dissertation: TRANSIENT MODELING OF TWO-STAGE AND VARIABLE REFRIGERANT FLOW VAPOR COMPRESSION SYSTEMS WITH FROSTING AND DEFROSTING Hongtao Qiao Doctor of Philosophy, 2014 Dissertation Directed By: Reinhard Radermacher, Professor Department of Mechanical Engineering This thesis presents the development of an advanced modeling framework for the transient simulation of vapor compression s...

Alat penukar kalor atau yang biasa disebut dengan heat exchanger adalah suatu peralatan dapat digunakan untuk menukar dari fluida ke lain punya perbedaan suhu, penukaran tersebut terjadi kontak langsung secara tidak langsung. Dilihat fungsinya sangat penting, maka alat ini luas dalam dunia perindustrian. Ada banyak macam seperti contohnya Plate Heat Exchanger (PHE). (PHE) merupakan salah satu j...

In this research, the application of heat pipes in the air handler dedicated to decoupling dehumidification from cooling to reduce energy consumption was simulated and investigated by simulations and experimental studies. The cooling load profiles and heat pipes with effectiveness of 0.45 and 0.6, respectively, were evaluated in achieving the desired space conditions and calculated hour by hour...

By increase in the power of computer systems and enhanced power of the components and their temperature, including the central processing unit (CPU), cooling just by the air is not effective and there is need for more powerful systems to cool down and increase the power of the cooling system. In this article simulation of the heat exchanger material of the fluid cooling system has been studied ...

The present study evaluated the thermodynamic characteristics of a prototype respiratory heat and moisture exchanger (HMS), particularly its ability to prevent cold injury to the face. The HME comprised a thermally insulated oro-nasal mask with a cylindrical heat and moisture exchanger protruding from the centre of the mask. The heat exchanging unit contained an aluminium “honeycomb” structure ...

Energy saving is major matter in our global world, and heat exchanger is very useful for energy saving. Of course heat exchanger is most significant component for chemical reaction, distillation, dissolution, crystallization, fermentation etc. So the correct selection of heat exchanger is important in these processes. Spiral tube Heat Exchangers are known as excellent heat exchanger because of ...