Our rainfall simulator at work

Soil physical measurements and rainfall simulator researches were started in the first half of 2000s in the LSSA. From the soil physical measurements, the determination of porosity, porosity content and bulk density are based on the method developed by Ferenc Vér. The density results from this method are controlled by pycnometer measurements. In addition to the soil physical measurements hygroscopicity tests are also available. The water absorption and water permeation dynamics of the monoliths can also be measured by the function which fitted to the results and estimates the saturated water permeation.

The rainfall simulator experiments have started with a Pannon R-02 field rainfall simulator developed at the Soil Science Department of the Georgikon Univerity, Keszthely (recent name: Pannon University, Georgikon Faculty). The EU Life SOWAP project of the Geographical Institute’s Physical Geography Department provided new opportunities to the rainfall simulator researches. Within the framework of this project, a field rainfall simulator, developed by the researchers of the KU Leuven, was purchased.

In the 2010's, within the framework of cooperation with the ELTE LSA, a laboratory rainfall simulator was installed in the ELTE Lágymányosi Campus South building. This equipment is still unique in Central-Europe due to the 9 m drop forming height. The equipment is under continuous improvements, currently the control device and the drop-forming system are under renovation.

In 2013 within the framework of an awarded tender of the International Atomic Energy Agency (IAEA) and the support of the CSFK (MTA) Director-General Framework, a portable large field rainfall simulator was developed by our group. One of the rainfall simulator was delived to the Radioactive Waste Management Agency of the Atomic Energy Organization of Iran (IRWA). Depending on the emerging needs, all three type of rainfall simulator can be used to the rainfall simulator researches.

Laboratory measurements
  • Densitiy determination by pycnometer
  • Porosity and saturated hydraulic conductivity determination by undisturbed soil samples
  • Hygroscopicity test: Mitscherlich- and Kuron's hygroscopicity

Portable rainfall simulator (SP02 rainfall simulator, 2014)
    Drop formation: Veejet 80/100 spray nozzles
    Drop formation height: 3 m
    Pressure: 0.4 bar
    Target area: 6 m2
    Precipitation parameters: (10 mm h-1 < i < 100 mm h-1)
    Control: a computer-controlled, continuously variable intensity
Tested parameters: moisture dynamics, runoff dynamics, sediment charge, runoff chemical parameters (pH, EC, DOC and nitrogen content), sediment parameters (particle composition, pH, SOC and nutrient content). Thin section analysis of soil compaction and crust formation; changes in surface roughness, micro-morphological changes detection by image processing.

Portable rainfall simulator (by the KU Leuven, 2004)

    Drop formation: Fulljet 1/2 HH-40 WSQ spray nozzles
    Drop formation height: 2.5 m
    Target area: 0.25 m2
    Precipitation parameters: 50 mm h-1 < i < 80 mm h-1
    Control: manual

Laboratory rainfall simulator (ELTE LSA and CSFK cooperation, 2012)

    Drop formation: unique drop formation (i < 10 mm h-1) and Fulljet 1/2 HH-40 WSQ spray nozzles
(10 mm h-1 < i < 100 mm h-1)
    Drop formation height: 9 m
    Target area: 0.5 m2
    Precipitation parameters: adjustable intensity
    Monolith tilt: 0-45°
    Tested parameters: runoff, infiltration, sediment charge, water chemistry parameters of moisture run-off/infiltration (EC, pH, DOC, macronutrients), sediment quality (particle composition, SOC, macronutrients). In contaminated soils analysis of the spreading of pollutants, leaching-entrapment of fertilizers and pesticides. Thin section analysis of soil compaction and crust formation; changes in surface roughness, micro-morphological changes detection by image processing