As global warming has raised more critical concerns in recent years, refrigerants with high global warming potentials (GWP) are facing the challenges of being phased out. R410A, with a GWP of 2,088, has been widely used in residential air-conditioning and heat pump systems. A potential substitute for R410A is R32, which has a GWP of 675. This paper investigates the performance difference of R41...

Abstract: In the present study the effect of thermomechanical treatment (cold work and annealing) on the transformation behavior of NiTi shape memory alloys was studied. Differential scanning calorimetry was used to determine transformation temperature and its relation to precipitates and defects. Three alloys including Ti-50.3at.% Ni, Ti-50.5at.% Ni (reclamated orthodontic wires) and 50.6at...

The crystallization behavior of the supercooled bulk metallic glass-forming Zr41Ti14Cu12Ni10Be23 liquid was studied with different heating and cooling rates. A rate of about 1 K/s is sufficient to suppress crystallization of the melt upon cooling from the equilibrium liquid. Upon heating, in contrast, a rate of about 200 K/s is necessary to avoid crystallization. The difference between the crit...

today air conditioning systems have been considered by all people as one of welfarerequirements in buildings and closed environments. since a considerable part of energy lossoccurs in ordinary modern systems, new strategies and solutions are developed in the field inorder to save amount of energy consumption and observe environmental considerations. fuzzycontrol is one of these methods which pr...

In this paper the changes in the heat capacity of cooling towers has been investigated as a result of injecting combustion products of boilers. In the tower, the air is re-heated through mixing with hot flue gas after passing through the heat exchangers. As a result of this process, the draft of the cooling tower is increased. The additional produced draft depends on the ambient temperature and...

In this paper the changes in the heat capacity of cooling towers has been investigated as a result of injecting combustion products of boilers. In the tower, the air is re-heated through mixing with hot flue gas after passing through the heat exchangers. As a result of this process, the draft of the cooling tower is increased. The additional produced draft depends on the ambient temperature and...

Many components of the storage ring and front ends in the third generation of light sources are subjected to high heat loads from intense x-rays. Temperature rises and thermal stresses in these components must be kept within acceptable limits of critical heat flux and low-cycle fatigue failure. One of the design solutions is to improve heat transfer to the cooling water either by increasing wat...