Vol 93, No 7 (2004)

In the article are compared the characteristics of natural refrigerants: air, water, hydrocarbons, carbon dioxide and ammonia that are used in refrigeration technique. The assessment of energy efficiency of different circuits of refrigeration installation with CO2 in the lower and NH3 in the upper branch and of a two-stage ammonia installation is presented. Ammonia installations with boiling CO2 as a pseudo coolant are also considered. For the version of installations with two evaporating temperatures a comparison of the cascade (CO/ NH3) circuit with a cascade-compound circuit proposed by the authors is given.

Results of the investigation of the first Russian prototype of Stirling refrigeration machine for moderate refrigeration are presented. Л test facility is described, experimental characteristics of the machine are presented and factors influencing its operational efficiency are evaluated. Analytical relationships of refrigerating capacity, drive power and coefficient of performance from helium pressure in the internal loop of the machine are obtained.

Few things are progressing as fast today as the HVAC market. More recently, some ten years ago, a split system seemed like a miracle of foreign technology, and today an ordinary consumer easily operates with such concepts as “chiller”, “fan coil”, “central air conditioner”. These technical terms, previously known only to specialists, are becoming as familiar in ordinary vocabulary as the once “industrial and semi-industrial” air conditioning systems themselves are becoming familiar in equipping apartments and cottages. Chiller-fan coil systems have been on the market for a few years, but it took time for them to gain some popularity, although even now the peak of demand is still far away. The next step in air conditioning is being made not only because a certain critical mass of users of household split systems has been reached. Pragmatic requirements for the quality of life dictate the choice of modern, environmentally friendly and energy-saving technologies. Engineering systems, especially in the construction of modern housing and office buildings, are given great attention today, despite the fact that they are not an investment priority

On June 25, 2004, a technical seminar of the company "Bitzer Kuhlmashinenbau" took place in St. Petersburg. The organizer was ACC, a young company that is an integrated supplier of refrigeration equipment and its components for Russian manufacturers of commercial and industrial refrigeration.
Representatives of the "Bitzer" company took part in the seminar: the head of the technical service, Mr. Rolf Blumhardt (Germany), the leading technical specialist of "Bitzer CIS" (Moscow) Dmitry Kornivets, the employees of the "ACC" company and its clients from Moscow, Saratov, Yekaterinburg and Krasnodar

In March 2004, at the key European exhibition of thermal insulation materials ISO in the German city of Wiesbaden, representing 120 participants from 11 countries, ARMACELL was awarded the international quality award ISO Award 2004. The international jury recognized the thermal insulation material ARMAFLEX® as the best among analogues, explaining his decision: “The invention of ARMAFLEX®, the world's first flexible insulation material, marked the birth of an entire industry of flexible technical thermal insulation. ARMAFLEX® has excellent technical characteristics that are constantly getting better

Refrigeration units are installed in the machine or utility rooms of the trading floor so that the compressor and condenser do not overcool during the cold season, or when another solution is not possible (for example, when placing monoblocks or units directly in commercial refrigeration equipment with autonomous cold supply).

Numerous publications about the apparatus "Multiplaz-2500", which until now appeared in various publications, were of a popular scientific nature.

The article presents a new program for calculating the heat transfer coefficient and pressure drop during the condensation of refrigerants inside smooth pipes when the machine is running on pure freons or their mixtures. The program is based on the study of models of flows formed during the condensation process.