Tag Archives: temperature

760–766 E. Kucuktopcu, B. Cemek and P. Banda
Determination of poultry house indoor heating and cooling days using degree-day method
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Determination of poultry house indoor heating and cooling days using degree-day method

E. Kucuktopcu*, B. Cemek and P. Banda

University of Ondokuz Mayis, Faculty of Agriculture, Department of Agricultural Structures and Irrigation, TR 55139 Samsun, Turkey
*Correspondence: erdem.kucuktopcu@omu.edu.tr

Abstract:

In poultry production, degree-day values are used as fundamental design parameters considered among others in determining the extent of heating and cooling of poultry housing. In this study, heating and cooling data values for each of broiler production period were determined using the degree-day method. The total length of the experiment was 123 days which corresponds to 3 growing periods. The inside and outside air temperatures of the poultry house were measured using air temperature data loggers positioned at different points and heights within and outside broiler house. Knowledge of heating and cooling day values is important as it necessitates the provision and maintenance of ideal bird’s production conditions and ensuring the economic viability of the enterprise through optimized energy consumption.

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700–706 J. Hart, and V. Hartová
The next generation of multiple temperature sensor
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The next generation of multiple temperature sensor

J. Hart¹,* and V. Hartová²

¹ Czech University of Life Sciences Prague (CULS), Faculty of Engineering, Department of Technological Equipment of Buildings, Kamýcká 129, CZ165 21 Prague, Czech Republic
² Czech University of Life Sciences Prague (CULS), Faculty of Engineering, Department of Vehicles and Ground Transport, Kamýcká 129, CZ165 21 Prague, Czech Republic
*Correspondence: janhart77@gmail.com

Abstract:

Long-term and short-term measurements of temperature at different depths in soil have always been very complicated. The solution that was used until now was measuring using soil thermometers. Measurements were done at shallow depths and generally only allowed for measuring of one temperature, and always at the one depth which was determined for the measurement (normally 5, 10, 20, 50, 100, 150 and 300 cm). These problems were relatively limiting and impractical. It was therefore necessary to devise an alternative for a simple and effective solution that would eliminate these disadvantages – it was necessary for a probe to allow temperature to be measured at different depths at one measuring point without having to change its position. A requirement simultaneously arose for the need to be able to measure temperatures at greater depths, and a multiple probe was therefore conceived consisting of a rod for dynamic penetration tests.

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1488–1497 P. Vaculik, L. Chladek, M. Prikryl, A. Smejtkova and P. Brany
The temperature changes of barley malt during its disintegration on a two roller mill
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The temperature changes of barley malt during its disintegration on a two roller mill

P. Vaculik*, L. Chladek, M. Prikryl, A. Smejtkova and P. Brany

Czech University of Life Sciences Prague, Faculty of Engineering, Department of Technological Equipment of Buildings, Kamýcká 129, CZ 165 21 Prague 6-Suchdol, Czech Republic; *Correspondence: vaculik@tf.czu.cz

Abstract:

This article discusses the change of temperature during disintegration on two roller mill. The production of barley and its treatment to malt is first step of beer brewing. The malt is the produced in malt plants. Crushing the malt is realized in only the brewery and is a core activity of brewing technology. This operation is performed both in craft breweries and in industrial brewery. This article therefore is focused on the theory of crashing solid phase with a respect of development of heat. Grinding barley malt is realised using mills of various designs or disintegrators. They are widely used mills with 2, 4, 5, 6 grinding cylinders. These roller mills are used in many other applications, not only in industrial food or drink production. For next treatment solid phase should be broken into smaller pieces (comminuted). The greater the extent of comminution, the large the surface area for impact on next treatment. The amount of mechanical energy converted to heat energy depends on the principle of the process disintegration and other parameters, i.e. distance of grinding gap, capacity, mechanical properties of crashing material etc. For these reasons, it is important to pay attention to the temperature change of barley malt during its disintegration on a mill.

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1434–1441 A. Põldvere, A. Tänavots, R. Saar, S. Sild and L. Lepasalu
Effect of heat treatment at constant 120 °C temperature on the rheological and technological properties of pork
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Effect of heat treatment at constant 120 °C temperature on the rheological and technological properties of pork

A. Põldvere¹⋅²⋅*, A. Tänavots², R. Saar¹, S. Sild¹ and L. Lepasalu¹

¹Estonian University of Life Sciences, Institute of Veterinary Medicine and Animal
Sciences, Department of Food Science and Technology, F.R reutzwaldi 56/5,
EE51014 Tartu, Estonia
²Estonian University of Life Sciences, Institute of Veterinary Medicine and Animal
Sciences, Department of Animal Genetics and Breeding, F.R. Kreutzwaldi 62,
EE51014 Tartu, Estonia
³Estonian Pig Breeding Association, Aretuse 2, EE61411 Märja, Tartumaa, Estonia
*Correspondence: aarne.poldvere@emu.ee

Abstract:

The aim of the study was to evaluate the influence of low-temperature heat treatment on the physical and technological properties of pork. The Longissimus thoracis muscles from four pigs were used to determine the quality indicators of pork at 24 hours after slaughtering. Meat samples were cooked at constant 120 °C in a cooking bag until the internal temperatures of 62, 67, 72, 77 and 82 °C. Raw meat was the darkest and differed considerably (P < 0.05) from the heat-treated meat. The colour values of the heat-treated meat differed slightly among internal temperature phases. The ultimate pH value of raw meat also differed significantly (P < 0.05) from that of cooked meat. The pH value of cooked meat varied only within the range of 0.05 units. The electrical conductivity of muscle decreased gradually as the temperature increased. In case of heat-treated meat, the cooking loss increased considerably (from 18.88% to 31.73%) along with the increase in the internal temperature. The Warner-Bratzler shear force value was the highest (38.50 N) in the meat cooked until 77 °C, and the lowest (28.51 N) in that cooked until 67 °C. Strong negative correlation (P < 0.001) between electrical conductivity and cooking loss was observed during the heating procedure. Heat treatment can significantly decrease the electrical conductivity and increase the cooking loss of meat. Meat was the toughest when the internal temperature was 77 °C. However, the best rheological properties were observed in the meat cooked until the internal temperature of 72 °C.

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1078–1087 M. Müller and R. Chotěborský
Impact strength behaviour of structural adhesives
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Impact strength behaviour of structural adhesives

M. Müller* and R. Chotěborský

Department of Material Science and Manufacturing Technology, Faculty of
Engineering, Czech University of Life Sciences, Kamýcká 129, CZ 165 21 Prague,
Czech Republic
*Correspondence: muller@tf.czu.cz

Abstract:

A cohesive force at an adhesive bond is one of the limit for a strength of an adhesive bonding. This study is focused on an impact force of an adhesive. Samples without a notch were cast in the casting mould at a laboratory temperature with a normal pressure. The instrumentation microcharpy test equipment was used for the evaluation of the impact force. The samples were tempered at a laboratory temperature, 40 °C and 60 °C. Results showed that the temperature of the specimens influenced the impact strength, the toughness and the maximum deformation of the adhesives. Higher temperature decreased the impact force but it increased the toughness. The hardness Shore D of commercial filled two-component epoxies is comparable. A nonhomogeneity of adhesives distinguished for a porosity was found by the investigation of a fracture surface.

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768–778 M. Hromasová and M. Linda
Analysis of rapid temperature changes
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Analysis of rapid temperature changes

M. Hromasová* and M. Linda

Czech University of Life Sciences in Prague, Faculty of Engineering, Department of Electrical Engineering and Automation, Kamycka 129, CZ165 21 Praha – Suchdol, Czech Republic
*Correspondence: hromasova@tf.czu.cz

Abstract:

 The analysis of rapid temperature changes in the dynamic system is described in the paper. Temperature changes are in range of tens of milliseconds. The sensor we used has a significant influence on the dynamic system. In these cases we need to use thermocouples that have appropriate transfer characteristics and can be manufactured with a low time constant. The time constant directly corresponds with weight and size of the sensor. The quality factor is usually in a range between 0.98 and 0.995. Information about the temperature course is particularly important in the field of dynamic systems, e.g. agricultural machines where the switching components are overloaded by pulse switching of technology systems. For the object analysis we use the thermocouples with diameter 0.012 mm with non-encapsulated finish and 0.12 mm with suppression of interference impact and comparative temperature fluctuation. For the analysis of dynamic temperature changes we conduct a measurement with a load factor change, which is the mean value of power change, expressed as ratio of the pulse duration to the delay between pulses, this way we will affect the measurement conditions. As a solution we use measurement methods for a steady state, an impulse test and a method of local measurement of temperature. Compared to a real principle of a component we do not increase temperature of the environment during experiments. The results of measurement can be applied for design and implementation of switching systems for electronic circuits with signal modulation and power load.

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228–235 J. Said, Š. Boďo, T. Saady, R. Gálik, S. Sardary and K. Abbas
Effect of broiler chickens living conditions on results of fattening
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Effect of broiler chickens living conditions on results of fattening

J. Said², Š. Boďo¹*, T. Saady², R. Gálik¹, S. Sardary² and K. Abbas²

¹Department of Production Engineering, Faculty of Engineering, Slovak University of
Agriculture in Nitra, Tr. A. Hlinku 2, SK 949SK 76 Nitra, Slovak Republic
²Agricultural College, Salahaddin University-Erbil, Karkuk St. Erbil, Kurdistan region,
Republic of Iraq
*Correspondence: stefan.bodo@uniag.sk

Abstract:

This work was aimed to monitor outdoor temperature, air humidity and internal microclimate conditions in broilers house during summer days, the temperature and the quality of bedding material as well as bird density. To evaluate the quality of litter we set three-tier system. If the litter dry and hard – value was ‘1’ if it was moist and supple – value was ‘2’, and if it was wet – value was ‘3’. The measurements were carried out on the 10th and 20th days of chickens age. Air temperature was monitored by (logger Comet R 3120) thermometer and for the measurement of the litter temperature used a non-contact thermometer (Raytek Raynger ST). To find out the birds density a thermocamera (Guide TP8S) for thermal imaging was used and subsequent shots are evaluated the birds stocking density. If the bird density high, value was ‘1’, if the bird density median, value was ‘2’ and if the density low, value was ‘3’. The hall was divided into 33 rectangular shapes. Results showed that the bedding quality averageed 1.2 on day 10 and 1.3 on day 20 of fattening (dry and hard). By comparing the P values and the significance level α (0.05), the value of 0.651 and 0.820 was found respectively for both age. No significance was detected between the litter temperature and the litter quality, also between bedding temperature and birds density. Intercomparison for bedding temperature and quality on days 10 and 20 a significant difference (0.000 < 0.05) was observed.

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1342-1350 A. Krofová and P. Kic
Ventilation and microclimatic conditions in the laboratory of adhesive bonding
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Ventilation and microclimatic conditions in the laboratory of adhesive bonding

A. Krofová¹* and P. Kic²

¹Czech University of Life Sciences Prague, Faculty of Engineering, Department Material Science and Manufacturing Technology, Kamýcká 129, CZ165 21 Prague, Czech Republic
²Czech University of Life Sciences Prague, Faculty of Engineering, Department of Technological Equipment of Buildings, Kamýcká 129, CZ 165 21 Prague, Czech Republic
*Correspondence: kofovaa@tf.czu.cz

Abstract:

The aim of this paper is to present the results of the research focused on the ventilation and microclimatic conditions in the laboratory of adhesive bonding. This special large underground laboratory is used for the research and teaching purposes during the whole year. The experiments provided in the laboratory require the use of different chemicals, adhesives and glues for the preparation of specimens for the testing various methods of adhesive bonding of metals and wood. There are intensively released chemical pollutants into the indoor environment of the laboratory during those processes. If there are taking place in the lab at the same time the classes with students (maximum 26 persons) there are also produced in that space products of the metabolism. To ensure the hygienic conditions for researchers and students, the laboratory must be adequately ventilated, but it is also necessary to ensure the desired thermal state of the environment. The results of measurements of indoor microclimate in this laboratory during the adhesive bonding processes are also presented in this paper. The experience and new knowledge useful for the future research and practical designs are summarized in the conclusions of this paper.

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494-499 P. Kic
Hot-air distribution in the floor heating
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Hot-air distribution in the floor heating

P. Kic

Czech University of Life Sciences Prague, Faculty of Engineering, Kamycka 129, CZ16521 Prague 6, Czech Republic;
Correspondence: kic@tf.czu.cz

Abstract:

The aim of this paper is to present results of measurement of hot-air floor heating system. The energy from fireplace directly heats the house near to the chimney and partly is distributed by the special ventilation under the floor in the whole heated room. The main principle is based on specially designed accumulative floors, consisting of a set of special chambers, which enable to heated air from the fireplace to flow through them. The layer of concrete floor is installed on the surface of these chambers. Hot-air can be intensively distributed around the house with time shift, but the air flow is not uniform and some places are warmer or colder. The results of measurements in the building showed that the accumulation in the floor compensates temperature differences. The result of proper application of this type of heating is a stable thermal comfort and saving of heating costs. Based on the results of measurements, practical recommendations for the design, installation and use of these types of heating were summarised in the conclusions.

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494-499 P. Kic
Hot-air distribution in the floor heating
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Hot-air distribution in the floor heating

P. Kic

Czech University of Life Sciences Prague, Faculty of Engineering, Kamycka 129, CZ16521 Prague 6, Czech Republic; e-mail: kic@tf.czu.cz

Abstract:

The aim of this paper is to present results of measurement of hot-air floor heating system. The energy from fireplace directly heats the house near to the chimney and partly is distributed by the special ventilation under the floor in the whole heated room. The main principle is based on specially designed accumulative floors, consisting of a set of special chambers, which enable to heated air from the fireplace to flow through them. The layer of concrete floor is installed on the surface of these chambers. Hot-air can be intensively distributed around the house with time shift, but the air flow is not uniform and some places are warmer or colder. The results of measurements in the building showed that the accumulation in the floor compensates temperature differences. The result of proper application of this type of heating is a stable thermal comfort and saving of heating costs. Based on the results of measurements, practical recommendations for the design, installation and use of these types of heating were summarised in the conclusions.

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