Method of calculation and analysis of joint operation of circuit loop of ground heat exchangers and heat pump

The method of heat calculation of the joint work of borehole heat exchangers and heat pump circuits in quasi-stationary regime is developed. The effect of the heat pump efficiency of heat exchangers design values, refrigerant superheating in evaporator, temperatures of heat source and heat consumer were analyzed on the base of the developed method

The numerical simulation of utilizer of soil heat and heat receiver in joint operation

The numerical model of the joint work of borehole heat exchanger and evaporator of the heat pump is developed. The design of the evaporator is shelltube heat exchanger with segmental baffles with a boiling in the U-shaped tubes. The design of ground heat exchanger is heat exchanger with two U-shaped tubes, which are arranged in a vertical borehole. The effect on the system temperature of soil, the multiplicity of circulation in the evaporator heat exchanger, the filler of borehole is modeled by the developed model

Influence of ground heat source parameters and consumer on characteristics of geothermal heat pump system

Features of heat supply system based on the use of ground are investigated with the help of the method of numerical simulation. The variables are the parameters characterizing the heat source and the consumer: the average temperature ofthe soil, the area and the radiative properties of the surface heating panels, air temperature of heated space. It was found that the maximum energy efficiency of the system is achieved by using a low-temperature floor heating system

Linguistic Diversity and Its Impact on Economic Policies and Political Decisions

The paper addresses the issue of linguistic diversity and its impact on economic policy and political decisions. Importance of the topic is illustrated by examination of optimal sets of official languages in the European Union. It is shown that alternative estimation methods of language disenfranchisement alter the order in which the languages enter the list of the official ones. Also, we present an overview of gametheoretic models of language acquisition, where individuals weigh costs and benefits of studying new languages. These models are used to predict actual distribution of language skills in a society and to compare it with the first-best outcome. The paper ends with estimation of our predictions on the basis of empirical analysis of European data.Game theory, linguistic models, communication benefits, costs of studying, official languages of the European Union, Nash equilibrium, public efficiency

Parameter selection for the supply system in a Pilger mill

The braking chamber in the supply system of a Pilger pipe mill is modernized. The influence of constant and variable parameters of the supply system on braking is studied. © 2013 Allerton Press, Inc

Controlling circular polarization of light emitted by quantum dots using chiral photonic crystal slab

We study the polarization properties of light emitted by quantum dots that are embedded in chiral photonic crystal structures made of achiral planar GaAs waveguides. A modification of the electromagnetic mode structure due to the chiral grating fabricated by partial etching of the wave\-guide layer has been shown to result in a high circular polarization degree $\rho_c$ of the quantum dot emission in the absence of external magnetic field. The physical nature of the phenomenon can be understood in terms of the reciprocity principle taking into account the structural symmetry. At the resonance wavelength, the magnitude of $|\rho_c|$ is predicted to exceed 98%. The experimentally achieved value of $|\rho_c|=81$% is smaller, which is due to the contribution of unpolarized light scattered by grating defects, thus breaking its periodicity. The achieved polarization degree estimated removing the unpolarized nonresonant background from the emission spectra can be estimated to be as high as 96%, close to the theoretical prediction