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Magistrsko delo je namenjeno predstaviti holističnega pristopa na področju zasnove modernih, malih kurilnih naprav. Predstavljene teoretične osnove, ki se navezujejo na lastnosti trdnih lesnih goriv in proces njihovega zgorevanja, predstavljajo fundamentalna znanja s katerimi je mogoče uspešno načrtovati zasnovo kurilnih naprav. Podrobneje so predstavljene še škodljive snovi, ki izstopajo iz sistema v katerem se odvija proces zgorevanja. Cilj razvoja malih kurilnih naprav na trdna lesna goriva je med drugim zagotovitev čistejšega zgorevanja, z namenom omejiti obremenitev okolja. Z upoštevanjem teoretičnega poznavanja področja zgorevanja trdnih lesnih goriv je mogoče načrtovati okolju prijazne in učinkovitejše naprave. Za namen uprizoritve procesa razvoja male kurilne naprave je predstavljen realen primer, kot ga je beležil avtor magistrskega dela tekom trajanja projekta. Predstavljen primer opisuje proces razvoja po principu »iz napak se učimo«. Tovrsten način razvoja dovoljuje hitre rezultate kadar je stopnja izkušenj in znanja sodelujočih oseb primerno visoka. Za reševanje dovolj enostavnih primerov zadostuje omenjena metoda, v primeru reševanja kompleksnejših problemov pa intuitivne metode ne zadostujejo več. Kot primer bolj primerne metode razvoja mailih kurilnih naprav na trdna lesna goriva je predstavljena računalniška dinamika tekočin. Za ta namen je bila pripravljena analiza predstavljene kurilne naprave s pomočjo numerične simulacije zgorevanja. Za namen popisa dogodkov v sloju goriva je bil uporabljen empirični ravnotežni model, ki služi za pridobitev sestave in lastnosti sinteznega plina, ki zapušča sloj. S pomočjo predpostavljenih in izračunanih robnih pogojev je bila izvedena numerična simulacija zgorevanja in prenosa toplote v mali kurilni naprav. Rezultati simulacije podajajo bogat vpogled v notranjost kurilne naprave tekom obratovanja, s tem pa možnost za razumevanje posledic različnih zasnov na obratovalne karakteristike, še pred njeno izdelavo. This master's thesis is intended to present a holistic approach in the design of modern, small boilers. Presented are the theoretical basics that relate to the properties of solid wood fuels and the process of their combustion. This represents the fundamental knowledge for the successful design of such devices. In addition, harmful substances, which emit from the system in which the combustion process takes place, are presented in more detail. The goal of developing small wood fired boilers is, among other things, ensuring cleaner combustion in order to reduce the environmental burden. With the appropriate theoretical knowledge of the field of combustion of solid wood fuels, it is possible to design environmentally friendly and efficient boilers. For the purpose of presenting of a development process, a realistic example is presented, as recorded by the author of this master's thesis. The presented example describes the process of development according to the principle "trial and error". This kind of development allows quick results when the level of experience and knowledge of the participants is quite high. In order to solve simple cases, this method is sufficient in the case of solving complex problems, intuitive methods are no longer sufficient. An example of a more suitable method of development is computational fluid dynamics, as a tool in the development of small combustion plants. For this purpose, an analysis of the presented combustion device was prepared by means of a numerical combustion simulation. For the purpose of capturing the events in the fuel layer, an empirical equilibrium model was used to obtain the composition and properties of the gas leaving the fuel bed. Using the assumed and calculated boundary conditions, a numerical simulation of the combustion was carried out. The results of the simulation give a rich insight into the events happening in the device, thus the possibility of understanding the consequences of different designs, which enables the validation of the design already in the design phase and does not require the physical creation of a prototype.