This paper investigates the results of a Second Law analysis applied to a mobile air conditioning system (MACs) integrated with an internal heat exchanger (IHX) by considering R152a, R1234yf and R1234ze as low global warming potential (GWP) refrigerants and establishing R134a as baseline. System simulation is performed considering the maximum value of entropy generated in the IHX. The maximum e...

The Organic Rankine Cycle (ORC) is commonly accepted as a viable technology to convert from low medium temperature geothermal energy into electrical energy. In practice, the reference for converting electricity subcritical simple ORC system. Over time, plants with more complex configurations (architectures) have been developed. open literature, large number of advanced architectures or introduc...

This paper presents technical assessment of environmentally friendly refrigerants as alternatives to R410A for window air conditioners. The alternative refrigerants that are studied for its replacement include R32, R600a, R290, R1234yf, R1234ze and a mixture of R32 (90% molar concentration) and R125 (10% molar concentration). Baseline experiments were performed on a window unit charged with R41...

An experimental investigation of oil retention and pressure drop characteristics for R1234yf, R134a and R410A with POE 100 is presented, for horizontal and vertical suction lines of 10.2 mm internal diameter. Conditions of operation include a saturation temperature of 13 °C and a superheat of 15 °C, with the superficial vapor velocity and the Oil in Circulation Ratio (OCR) both varied in the ra...

Air conditioning contributes significantly to building energy consumption in hot climate regions. In addition to greater cooling requirements in hot climates, cooling equipment efficiency decreases with increasing outdoor temperature. Therefore, it is advantageous to develop improved technologies that can achieve higher efficiency at high ambient conditions. In this paper, two novel compression...

In recent years, ejectors have received much attention because of their ability to reduce throttling losses and increase the efficiency of stationary and mobile air-conditioning systems. While much of the initial research was carried out with high pressure fluids, such as carbon dioxide, it was soon discovered that ejectors can also offer significant advantages in systems that utilize low press...

Isothermal vapour−liquid equilibrium (VLE) for four binary systems involving R1234yf (R1234yf + R134a, R152a, R1233zd(E) and R1233xf) were measured at temperatures from 278.15 to 348.15 K. The experiments conducted by means of a “static−analytic” apparatus with phase analysis via gas chromatography, resulting uncertainties 0.6 K temperature, 8 kPa pressure maximum 0.007 vapour liquid mole fract...