The sensitivity and linearity of linear variable differential transformers as displacement transducers is discussed. The results of measurements on the variation of sensitivity with low temperatures are presented for a commercially available device; the Schlumberger Industries SM3, used in conjunction with its OD3 conditioning electronics. The sources contributing to the temperature dependence are discussed and suggestions concerning how this may be reduced are made. The SM3 is shown to be robust on thermal cycling and a versatile extensometer for use in the determination of the mechanical properties of materials at low temperatures. Indication is given of how it can be used for the measurement of the thermal contraction of sample materials and in monitoring movement during cooling of cryogenic structures.

Considering the demands for reduction of fuel consumption involved in generation of electrical energy needed for classical refrigeration systems, this method uses for freezing liquid nitrogen obtained as secondary product at oxygen production. The resulted nitrogen gas is discharged in the environment, and, being chemically inert, it does not contribute to harmful chemical components generation. This paper presents some aspects concerning raspberries and blueberries freezing using liquid nitrogen: duration of the process, freezing capacity, advantages and disadvantages of this modern method. Quick freezing of food products in a cryogenic freezer consist in the use of the latent heat of evaporation of the liquid nitrogen, as well as of the sensible heat of the vapors, whose temperature increase up to final temperature of the frozen product. The use of cryogenic freezing with liquid nitrogen and carbon-dioxide is regarded as the "century's revolution" in the food area.

Energy and economic performance of an organic Rankine cycle (ORC) system designed to recycle waste heat of a steam boiler was analysed. Optimisation of ORC system was performed by using the Cycle-Tempo software and the REFPROP program. The selected working fluid was R245fa. For the exhaust gases temperature of 163°C and mass flow rate of 11.83 kg/s, cooling water temperature of 20°C resulted a gross efficiency of 21.02% and a cost of 2987 €/kW, an electricity levelised cost of 102 €/kWh and a payback period of 5.5 years.

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The paper presents the experimental and theoretical study for temperature distribution around the cooling pipes of an ice rink pad. The heat transfer in the skating rink track is nonstationary and phase changing. In case of skating rinks equipped with pipe registers, the temperature field during the ice formation process can’t be modeled by analytical methods. The experimental research was targeted on finding the temperatures in several points of the pad and also details on ice shape and quality around the pipes. The temperatures measured on the skating ring surface using thermocouples is impossible due to the larger diameter of the thermocouple bulb compared with the air-water surfaces thickness. For this reason we used to measure the temperature by thermography method, thus reducing the errors The experimental results were compared against the numerical modeling using finite elements.