237 Agronomy Research Biosystem Engineering Special Issue 1, 237-243, 2011 Calculations of heated floor panel for resting places of piglets V. Zagorska 1 and U. Iljins 2 1 Institute of Mechanical Engineering, Latvia University of Agriculture, Liela iela 2, LV-3000, Jelgava, Latvia; e-mail: vzagorska@gmail.com 2 Latvia University of Agriculture, Faculty of Information Technologies; e-mail: uldis.iljins@llu.lv Abstract. The purpose of this paper is to show the use of mathematical physics in solving engineering problems with the help of the separation of variables method, using optimizing heating element – placement of the electrical wire or hot water tube in concrete panel housing. During the research heat flows from all 4 surfaces (right, left, upper, and bottom) were calculated, using obtained solutions for heat flow calculation. These calculations are required for constructing a more comfortable and energy efficient heating panel for newborn piglets. Key words: Method of separation of variables, heating distribution. INTRODUCTION The first days are the most critical in a piglet’s life (Fahmy & Bernhard, 1971; Furniss, 1986; Edwards & Malkin, 1986). Up to 80% of piglet losses occur in the first 3 days of their life and the majority of deaths are attributed to crushing (English & Morrison, 1984; Weary et al., 1998). To reduce piglet losses by crushing by the sow the nest area must be warm. However, because of economic and hygienic disadvantages, straw is becoming less common (Hoy & Ziron, 1998) and the modern practice is to use either electric or gas infrared heaters, or underground heaters with solid plates (Hoy & Ziron, 1998). In this article we will pay attention to the solid plates. For ensuring the comfort of piglets, concrete floor panels heated by electric current or hot water are used. If an electro-heated cable is placed in the panel’s body, the amount of heat conducted from the cable is the same along the whole cable length (Iljins & Ziemelis, 1996). If hot water circulating through tube is used, the amount of heat energy taken off the heater decreases along its length. Distribution of temperature over the working surface of the panel at different position x and y coordinates of heating elements, different heat transfer coefficients and variable heating element intensity have been calculated previously (Zagorska et al, 2010), using MS Excel software and obtained temperature distribution solution over the cross-section of the panel. The aim of the research is to find the solution for the heat flow’s determination from all 4 sides of the panel, evaluating variable: heating element intensity and heat transfer coefficients of the surfaces.