This paper deals with the heat exchange performance prediction of a counter flow double-tube condenser for binary natural refrigerant mixtures (propane/n-butane & propane/i-butane ). The local characteristics of the heat transfer and pressure drop are calculated using a prediction method developed by authors, and the total pressure drop, the overall heat transfer coefficient and the average hea...

in this work, experimental kinetics data of methane hydrate decomposition at temperatures ranging from 272.15 to 276.15 k and at pressures ranging from 10 to 30 bars were modeled by using chemical affinity. this model proposed a macroscopic model which is independent of any intermediate mechanism like heat or mass transfer. the results show there is good agreement with experimental data. also t...

in this article the effect of fouling on tube side and the overall performance of preheat exchangers of crude distillation unit of petroleum refinery have been investigated. for this purpose the experimental data of australian light crude oil in surface temperature of 200-260oc and the velocity between 0.25 to 0.4 m/s have been used. first, an overall dirty heat transfer coefficient was calcula...

In this study, the thermal performance of three kinds of roofs with different heat capacity and thermal conductivity under different external conditions has been investigated using a numerical method. For this purpose, the combined solar radiation, conduction and convection heat transfer were calculated implicitly in terms of a one-dimensional finite difference method. Different high and low so...

introduction drying foods, fruits and vegetables is a suitable method to reduce post-harvest losses of the crops. drying is considered as a simultaneous heat and mass transfer process. various physical, chemical and nutritional changes occur during drying of foods and are affected by a number of internal and external heat and mass transfer parameters. external parameters may include temperature...

in this work, removal of c. i. acid red 14 was investigated by pumice stone as a low cost adsorbent. various parameters such as initial dye solution, contact time and ph were studied. removal of dye were increased by increasing of contact time and initial dye solution and deceased by increasing of ph. three isotherm models were studied. linear and non-linear regression analyses were used for de...