Plate heat exchangers 2015 by Hoval USA

More catalogs by Hoval USA | Plate heat exchangers 2015 | 36 pages | 2017-03-17

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Page 29 of Plate heat exchangers 2015

system design 9  system design 9.2  design data 9.1  hoval caser design program the hoval caser design program is available for fast and accurate design of hoval plate heat exchangers  computer aided selection of energy recovery it runs under microsoft® windows and offers the following applications ■ secure planning with eurovent and tÜv-certified data ■ exact calculation of a specific hoval plate heat exchanger ■ calculation of all appropriate plate heat exchangers for a specific project ■ calculation of the efficiency class in accordance with en 13053 ■ calculation of leakage in accordance with eurovent ■ price calculation for the selected plate heat exchangers notice you can download the hoval caser design program free of charge from our home page hrs.hoval.com the program is also available as a windows dll file and can therefore be integrated into other spreadsheet programs on request when designing correct data is essential to achieve the desired values this is often particularly difficult in air handling installations because the specific density and specific heat are dependent on temperature also the water vapour contained in the air is very important for the design for an exact calculation of a plate heat exchanger the air conditions at entry to the exchanger are required exhaust air stream supply air stream extract air flowrate v11 [m3/s extract air temperature t11 [°c extract air rel humidity rh11 fresh air flowrate v21 [m3/s fresh air temperature t21 [°c fresh air rel humidity rh21 table 13:  design data the following errors should be avoided when collecting the data ■ volume flow is not equal to mass flow for an accurate design the mass flows of fresh and extract air should be known ■ for winter operation the humidity in the air is often estimated too high where does the humidity come from ■ are the temperatures fresh air extract air really as stated in practice or are they wishful thinking 9.3  positioning of unit and system layout hoval caser ■ where should the heat recovery unit be positioned ■ which is the optimum air path ■ which dimensions are allowed these questions are important when selecting a plate heat exchanger and should be thoroughly examined in advance little general recommendation can be given for positioning and air path only take care that condensate if present can drain freely and does not remain inside the exchanger thus causing a higher pressure drop this is always guaranteed with a downward extract air flow yet in practice all possible airflows and positions are used without any problems section 5.5 gives special tips for horizontal installation fresh air t21 rh21 extract air t11 rh11 exhaust air t12 rh12 supply air t22 rh22 fig 28:  function diagram and air conditions 27